KR20200003794A - High strength low thermal expansion alloy wire - Google Patents

Abstract

An object of the present invention is to provide an alloy wire having a necessary property as a high strength low thermal expansion alloy wire, and to provide an alloy wire that can use a wide range of conditions for heat treatment to obtain a desired hardness in the manufacture of the alloy wire. For this purpose, a high-strength low thermal expansion alloy wire having a predetermined alloy composition and crystal grains in which (Mo, V) C-based composite carbides are present, wherein the amounts of Mo, V and C included in the alloy wire are respectively [Mo]. , [V] and [C], the value of ([Mo] +2.8 [V]) / [C] is 9.6 or more and 21.7 or less, and Mo and V contained in the (Mo, V) C-based composite carbide When the quantity of V is {Mo} and {V}, respectively, the said high strength low thermal expansion alloy wire whose value of {Mo} / {V} is 0.2 or more and 4.0 or less is provided.

Description

High strength low thermal expansion alloy wire

This application claims the priority based on Japanese Patent Application No. 2017-083035 for which it applied on April 19, 2017, The whole content of these is integrated in this specification by reference.

In the present invention, it is desired to avoid the dimensional and shape change due to thermal expansion, but the high-strength low-expansion alloy wire used for low-degree transmission line core wire materials, wire rods for precision mechanical parts, etc., which may be heated during use. And a high strength low thermal expansion coating alloy wire.

Conventionally, various high strength low thermal expansion alloy wires are known. For example, Patent Document 1 (Japanese Patent Laid-Open No. 7-228947) discloses C: 0.1 to 0.4%, Si: 0.2 to 1.5%, Mn: 0.1 to 1.5%, and Ni: 33 to 42% by weight. , Co: 5.0% or less, Cr: 0.75 to 3.0%, V: 0.2 to 3.0%, B: 0.003% or less, O: 0.003% or less, Al: 0.1% or less, Mg: 0.1% or less, Ti: 0.1% or less , High strength low thermal expansion alloy wire containing 0.1% or less of Ca, remainder consisting of Fe and an unavoidable impurity, and having a relationship of 1.0% ≦ V + Cr ≦ 5.0% is disclosed.

Further, Patent Document 2 (Japanese Laid-Open Patent Publication No. 2002-256395) contains, in mass%, C: 0.1 to 0.4%, V: more than 0.5% to 3.0%, and Ni: 25 to 50%, and 2 ≦ A high-strength low thermal expansion alloy wire which satisfies V / C? 9 and is excellent in torsional characteristics characterized by consisting of residual Fe and unavoidable impurities is disclosed. Patent Document 2 discloses that the high strength low thermal expansion alloy wire may contain 5% or less of one, two or more of Al, Mo, Ti, Nb, Ta, Zr, Hf, W, and Cu in total.

In addition, Patent Document 3 (Japanese Patent Laid-Open No. 2003-82439) discloses, by weight, C: 0.20 to 0.40%, Si: 0.8%, Mn: 1.0%, P: 0.050%, and S: 0.015%, Cu: ≤1.0%, Ni: 35-40%, Cr: ≤0.5%, Mo: 1.5-6.0%, V: 0.05-1.0%, O: ≤0.015%, N: ≤0.03%, Mo /V≥1.0 and (0.3Mo + V) ≥4C, which has a composition consisting of the balance Fe and unavoidable impurities, and the average coefficient of linear thermal expansion up to 20-230 ° C and 230-290 ° C, respectively. An invar alloy wire excellent in strength and torsion characteristics, which is 3.7 × 10 ⁻⁶ or less and 10.8 × 10 ⁻⁶ or less, is disclosed.

Japanese Patent Application Laid-Open No. 7-228947 Japanese Laid-Open Patent Publication No. 2002-256395 Japanese Laid-Open Patent Publication No. 2003-82439

In the conventional high strength low thermal expansion alloy wires disclosed in Patent Literatures 1 to 3, precipitation hardening is achieved by aging heat treatment to achieve high hardness, but the range of conditions (temperature and holding time of this temperature) in which aging heat treatment is optimal For example, since the range of optimal conditions is narrow in order to obtain maximum hardness, it is difficult to obtain desired hardness.

Therefore, the present invention is an alloy wire having the properties (for example, high strength, high twist count value, good ductility, low thermal expansion rate, etc.) necessary as a high strength low thermal expansion alloy wire, the desired hardness in the production of the alloy wire An object of the present invention is to provide an alloy wire that can be used under a wide range of conditions for heat treatment to obtain the

The present inventors appropriately control the composition of the alloy wire, the composition of the carbide present in the crystal grains, the dispersion state of the carbide present in the crystal grains, and the like, so that the characteristics (for example, high strength and high torsion number values) required as high strength low thermal expansion alloy wires are controlled. As an alloy wire having good ductility, low thermal expansion ratio, and the like, it has been found that an alloy wire which can use a wide range of conditions for heat treatment to obtain a desired hardness when the alloy wire is manufactured can be realized, and thus, the present invention has been completed.

The present invention provides the following high strength low thermal expansion alloy wires and high strength low thermal expansion coating alloy wires.

(1) In mass%, C: 0.1% or more and 0.4% or less, Si: 0.1% or more and 2.0% or less, Mn: more than 0% and 2.0% or less, Ni: 25% or more and 40% or less, V: 0.5% or more and 3.0% Mo: 0.4% or more, 1.9% or less, Cr: 0% or more and 3.0% or less, Co: 0% or more and 3.0% or less, B: 0% or more and 0.05% or less, Ca: 0% or more and 0.05% or less, Mg: 0 % Or more 0.05% or less, Al: 0% or more and 1.5% or less, Ti: 0% or more and 1.5% or less, Nb: 0% or more and 1.5% or less, Zr: 0% or more and 1.5% or less, Hf: 0% or more and 1.5% or less , Ta: 0% or more and 1.5% or less, W: 0% or more and 1.5% or less, Cu: 0% or more and 1.5% or less, O: 0% or more and 0.005% or less, and N: 0% or more and 0.03% or less, and A high strength low thermal expansion alloy wire whose balance is composed of Fe and unavoidable impurities,

In the crystal grains of the alloy wire, (Mo, V) C-based composite carbide containing both Mo and V is present,

When the amounts of Mo, V, and C contained in the alloy wire are [Mo], [V], and [C], respectively, the value of ([Mo] +2.8 [V]) / [C] is 9.6 or more 21.7 Is less than

When the amounts of Mo and V contained in the (Mo, V) C-based composite carbide are {Mo} and {V}, respectively, the value of {Mo} / {V} is 0.2 or more and 4.0 or less, wherein the high-strength low thermal expansion Alloy wire.

(2) In the crystal grains, the density of the (Mo, V) C-based composite carbide is 10 / μm ² or more, and is 150 nm or less in diameter with respect to the total number of the (Mo, V) C-based composite carbide. The high strength low thermal expansion alloy wire of (1) whose ratio of the number of the said (Mo, V) C type complex carbide of 50% or more is 50% or more.

(3) In mass%, Cr: more than 0% and 3.0% or less,

When the amounts of Mo, V and Cr contained in the alloy wire are [Mo], [V] and [Cr], respectively, the value of ([Mo] + [V]) / [Cr] is 1.2 or more, ( The high strength low thermal expansion alloy wire of 1) or (2).

(4) In mass%, Co: contains more than 0% and 3.0% or less,

When the amounts of Co and Ni contained in the alloy wire are [Co] and [Ni], respectively, any of (1) to (3) in which [Co] + [Ni] is 35% or more and 40% or less. The high strength low thermal expansion alloy wire of any one of Claims.

(5) (1) to (%) containing, in mass%, B: greater than 0% and 0.05% or less, Ca: greater than 0% and 0.05% or less, and Mg: greater than 0% and 0.05% or less. The high strength low thermal expansion alloy wire in any one of (4) paragraph.

(6) In mass%, Al: greater than 0% and 1.5% or less, Ti: greater than 0% and 1.5% or less, Nb: greater than 0% and 1.5% or less, Zr: greater than 0% and 1.5% or less, Hf: greater than 0% and 1.5% Or (1) to (5), which includes one or two or more of Ta: greater than 0% and 1.5% or less, W: greater than 0% and 1.5% or less, and Cu: greater than 0% and 1.5% or less. The high strength low thermal expansion alloy wire of any one of Claims.

(7) The high strength low thermal expansion alloy wire according to any one of (1) to (6), wherein the mass% contains N: more than 0% and 0.03% or less.

(8) The high strength low thermal expansion alloy wire according to any one of (1) to (7), wherein the tensile strength is 1400 MPa or more.

(9) The high-strength low thermal expansion alloy wire according to any one of (1) to (8), wherein the twist count value measured at a distance between the mark points 100 times the final wire diameter of the alloy wire is 20 or more times.

(10) The high strength low thermal expansion alloy wire according to any one of (1) to (9), wherein the elongation is 0.8% or more.

(11) Average linear thermal expansion coefficient between 2 points from 15 degreeC to 100 degreeC is 3 * 10 <^-6> / degreeC or less (15-100 degreeC), and average linear thermal expansion between two points from 15 degreeC to 230 degreeC coefficient of 4 × 10 ^-6 / ℃ or less (15~230 ℃), an average coefficient of linear thermal expansion between two points less than 4 × 10 ^-6 / ℃ (100~240 ℃) of from 100 ℃ to 240 ℃, also The high strength according to any one of (1) to (10), wherein the mean coefficient of linear thermal expansion between two points from 230 ° C to 290 ° C is 11 × 10 ^-6 / ° C or lower (230 to 290 ° C). Low thermal expansion alloy wire.

(12) A high strength low thermal expansion coating alloy wire comprising the high strength low thermal expansion alloy wire according to any one of (1) to (11), and an Al coating layer or Zn coating layer formed on the surface of the high strength low thermal expansion alloy wire.

According to the present invention, an alloy wire having characteristics necessary for high strength low thermal expansion alloy wire (for example, high strength, high torsion number, good ductility, low thermal expansion rate, etc.), and a heat treatment for obtaining a desired hardness in the production of alloy wire Provided are alloy wires and clad alloy wires which can be used in a wide range of conditions. Although the alloy wire and the coated alloy wire of the present invention are desired to avoid dimensional and shape changes due to thermal expansion, high-strength low thermal expansion used for core wire materials of low-duty power transmission lines, wire rods for precision mechanical parts, etc., which may be elevated during use. It is useful as an alloy wire.

1 shows an example of a curve in which the horizontal axis is the aging temperature and the vertical axis is the tensile strength when the heating time is fixed at 6 hours and the heating temperature is changed between 610 to 650 ° C. to perform the aging heat treatment. It is a conceptual diagram showing.
FIG. 2 shows curves in which the horizontal axis is the aging temperature and the vertical axis is the tensile strength when the heating temperature is fixed at 650 ° C. and the heating time is varied between 30 minutes and 9 hours. It is a conceptual diagram which shows an example.

<Composition of alloy ship>

Hereinafter, the composition of the alloy wire of the present invention will be described. In addition, in this specification, "%" means the mass% except the case where it is specifically defined.

C: 0.1% or more and 0.4% or less

C is an essential element of the alloy wire of the present invention. C is effective for strengthening of solid solution and precipitation hardening by carbide formation and strengthening thereof. From the viewpoint of effectively exerting such effects of C, the content of C is adjusted to 0.1% or more, preferably 0.13% or more, and more preferably 0.15% or more. On the other hand, when C content is excess, ductility will fall and a linear thermal expansion coefficient will increase. Therefore, the content of C is adjusted to 0.4% or less, preferably 0.38% or less, and more preferably 0.36% or less.

Si : 0.1% or more and 2.0% or less

Si is an essential element of the alloy wire of the present invention. Si is available for consolidation of employment. From the viewpoint of effectively exhibiting such an effect of Si, the content of Si is adjusted to 0.1% or more, preferably 0.2% or more, and more preferably 0.3% or more. On the other hand, if the content of Si is excessive, the linear thermal expansion coefficient increases. Therefore, content of Si is adjusted to 2.0% or less, Preferably it is 1.7% or less, More preferably, it is adjusted to 1.3% or less.

Mn: greater than 0% and less than 2.0%

Mn is an essential element of the alloy wire of the present invention. Mn acts as a deoxidizer and is effective for strengthening solid solution. From the viewpoint of effectively exerting such effects of Mn, the content of Mn is adjusted to more than 0%, preferably 0.1% or more, and more preferably 0.2% or more. On the other hand, if the content of Mn is excessive, the linear thermal expansion coefficient increases. Therefore, the content of Mn is adjusted to 2.0% or less, preferably 1.8% or less, and more preferably 1.3% or less.

Ni : 25% or more and 40% or less

Ni is an essential element of the alloy wire of the present invention. Ni is effective for realizing a low linear thermal expansion coefficient. From the viewpoint of effectively exhibiting such an effect of Ni, the content of Ni is adjusted to 25% or more, preferably 30% or more, and more preferably 34% or more. On the other hand, when the content of Ni is excessive, the realization of the low coefficient of thermal expansion becomes difficult, and the alloy wire cost increases. Therefore, the content of Ni is adjusted to 40% or less, preferably 39% or less, more preferably 38% or less.

V: 0.5% or more and 3.0% or less

V is an essential element of the alloy wire of the present invention. V is effective for precipitation hardening by carbide formation and reinforcement thereof, and is effective for suppressing coarsening of carbides in grains and ductile deterioration through promoting fine precipitation of carbides in grains. From the viewpoint of effectively exhibiting such an effect of V, the content of V is adjusted to 0.5% or more, preferably 0.6% or more, more preferably 0.7% or more. On the other hand, if the content of V is excessive, the above-mentioned effect is saturated, and the increase of the effect suitable for the increase of the content is not obtained, and the coefficient of linear thermal expansion increases. Therefore, content of V is 3.0% or less, Preferably it is 2.8% or less, More preferably, it adjusts to 2.6% or less.

Mo : 0.4% or more and 1.9% or less

Mo is an essential element of the alloy wire of the present invention. Mo is effective for precipitation hardening and reinforcement by carbide formation, and is effective for suppressing coarsening of carbides in grains and ductile deterioration through promoting fine precipitation of carbides in grains. From the viewpoint of effectively exerting such effects of Mo, the Mo content is adjusted to 0.4% or more, preferably 0.5% or more, and more preferably 0.7% or more. On the other hand, when Mo content is excess, the said effect will be saturated, and the increase of the effect suitable for increase of content will not be acquired, and a linear thermal expansion coefficient will increase. Therefore, content of Mo is 1.9% or less, Preferably it is 1.7% or less, More preferably, it is adjusted to 1.5% or less.

([ Mo ] +2.8 [V]) / [C] value

When the amounts of Mo, V and C contained in the alloy wire of the present invention are [Mo], [V] and [C], respectively, the value of ([Mo] +2.8 [V]) / [C] is 9.6. It is more than 21.7. When the value of ([Mo] +2.8 [V]) / [C] is less than 9.6, the content of C becomes relatively excessive, and ductility decreases. Therefore, the value of ([Mo] +2.8 [V]) / [C] is adjusted to 9.6 or more, preferably 10.0 or more, and more preferably 10.8 or more. When the value of ([Mo] +2.8 [V]) / [C] is 9.6 or more, precipitation hardening and strengthening by carbide formation can be realized, and ductility can be optimized. On the other hand, when the value of ([Mo] +2.8 [V]) / [C] exceeds 21.7, the content of V and the content of Mo become relatively excessive, the effect of V and Mo is saturated, and the content increases. Increasing the effect that is suitable for the increase is not obtained, and the coefficient of linear thermal expansion increases. Therefore, the value of ([Mo] +2.8 [V]) / [C] is adjusted to 21.7 or less, preferably 21.3 or less, and more preferably 21.0 or less.

Although the alloy wire of this invention contains the said essential element and remainder consists of Fe and an unavoidable impurity, it can contain 1 type, or 2 or more types of the following arbitrary elements and impurities as needed.

Cr : 0% or more and 3.0% or less

Cr is an arbitrary element of the alloy wire of the present invention. Cr is available for consolidation of employment. When it is desired to effectively exert such effects of Cr, the content of Cr is adjusted to more than 0%, preferably at least 0.1%, more preferably at least 0.3%. On the other hand, when Cr content is excessive, strength and ductility will fall by formation of coarse carbide, and a linear thermal expansion coefficient will increase. Therefore, the Cr content is adjusted to 3.0% or less, preferably 2.5% or less, more preferably 2.0% or less.

When the amounts of Mo, V, and Cr contained in the alloy wire of the present invention are [Mo], [V], and [Cr], the value of ([Mo] + [V]) / [Cr] is preferable. More than 1.2. When the value of ([Mo] + [V]) / [Cr] is less than 1.2, the content of Cr becomes relatively excessive, precipitation hardening is inhibited by formation of coarse carbide, and ductility is lowered. Therefore, the value of ([Mo] + [V]) / [Cr] is adjusted to 1.2 or more, preferably 1.3 or more, and more preferably 1.5 or more. Although the upper limit of the value of ([Mo] + [V]) / [Cr] is not specifically limited, Preferably it is 8.0 or less, More preferably, it is 6.0 or less.

Co: 0% or more and 3.0% or less

Co is an arbitrary element of the alloy wire of the present invention. Co has the same effect as Ni and is effective for stabilizing the coefficient of thermal expansion by raising the Curie temperature. When it is desired to effectively exhibit such an effect of Co, content of Co is adjusted to more than 0%, Preferably it is 0.1% or more, More preferably, it is 0.3% or more. On the other hand, when Co content is excessive, alloy wire cost will increase and a linear thermal expansion coefficient will increase. Therefore, content of Co is adjusted to 3.0 or less, Preferably it is 2.8 or less, More preferably, it is 2.5% or less.

[Co] + [Ni] is preferably 35% or more and 40% or less when the amounts of Co and Ni contained in the alloy wire of the present invention are [Co] and [Ni], respectively. If [Co] + [Ni] is less than 35%, it is difficult to realize a low linear thermal expansion coefficient. Therefore, [Co] + [Ni] becomes like this. Preferably it is 35% or more, More preferably, it is 36% or more, More preferably, it adjusts to 37% or more. When [Co] + [Ni] is 35% or more, a low linear thermal expansion coefficient can be realized. On the other hand, when [Co] + [Ni] exceeds 40%, it is difficult to realize a low coefficient of thermal expansion and the alloy wire cost increases. Therefore, [Co] + [Ni] is preferably adjusted to 40% or less, more preferably 39.5% or less, and even more preferably 39% or less.

B: 0% or more and 0.05% or less

B is an arbitrary element of the alloy wire of the present invention. B is effective for improving the hot workability by strengthening the grain boundary and strengthening the grain boundary oxidation resistance. When it is desired to effectively exhibit such an effect of B, content of B is adjusted to more than 0%, Preferably it is 0.001% or more, More preferably, it is 0.002% or more. On the other hand, when content of B is excess, hot workability will fall. Therefore, the content of B is adjusted to 0.05% or less, preferably 0.03% or less, and more preferably 0.01% or less.

Ca: 0% or more and 0.05% or less

Ca is an arbitrary element of the alloy wire of the present invention. Ca is effective for the improvement of hot workability by S fixation. When it is desired to effectively exhibit such an effect of Ca, content of Ca is adjusted to more than 0%, Preferably it is 0.005% or more, More preferably, it is 0.01% or more. On the other hand, when Ca content is excess, hot workability will fall. Therefore, the content of Ca is adjusted to 0.05% or less, preferably 0.04% or less, and more preferably 0.03% or less.

Mg: 0% or more and 0.05% or less

Mg is an arbitrary element of the alloy wire of the present invention. Mg is effective for the improvement of hot workability by S fixation. When it is desired to effectively exert such effects of Mg, the content of Mg is adjusted to more than 0%, preferably 0.01% or more, more preferably 0.015% or more. On the other hand, if content of Mg is excess, hot workability will fall. Therefore, content of Mg is adjusted to 0.05% or less, Preferably it is 0.045% or less, More preferably, it is adjusted to% 0.04 or less.

Al: 0% or more and 1.5% or less

Al is an arbitrary element of the alloy wire of the present invention. Al is effective for removing oxide inclusions due to deoxidation effect, strengthening of solid solution, and precipitation hardening and strengthening thereof. When it is desired to effectively exhibit such an effect of Al, content of Al is adjusted to more than 0%, Preferably it is 0.005% or more, More preferably, it is 0.01% or more. On the other hand, when the content of Al is excessive, ductility decreases, an increase in the coefficient of thermal expansion and an increase in the alloy wire cost occur. Therefore, the Al content is adjusted to 1.5% or less, preferably 1.3% or less, and more preferably 1.0% or less.

Ti : 0% or more and 1.5% or less

Ti is an arbitrary element of the alloy wire of the present invention. Ti is effective for precipitation hardening and strengthening thereof, and can be used as an alternative element of V or Mo. When it is desired to effectively exhibit such an effect of Ti, content of Ti is adjusted to more than 0%, Preferably it is 0.001% or more, More preferably, it is 0.005% or more. On the other hand, when the content of Ti is excessive, a decrease in aging hardening ability, a decrease in ductility, an increase in thermal expansion coefficient, and an increase in alloy wire cost occur. Therefore, the content of Ti is adjusted to 1.5% or less, preferably 1.3% or less, and more preferably 1.0% or less.

Nb : 0% or more and 1.5% or less

Nb is an arbitrary element of the alloy wire of the present invention. Nb is effective for precipitation hardening and strengthening thereof, and can be used as an alternative element of V or Mo. When it is desired to effectively exhibit such an effect of Nb, content of Nb is adjusted to more than 0%, Preferably it is 0.01% or more, More preferably, it is adjusted to 0.02% or more. On the other hand, when the content of Nb is excessive, a decrease in aging hardening ability, a decrease in ductility, an increase in thermal expansion coefficient, and an increase in alloy wire cost occur. Therefore, the content of Nb is adjusted to 1.5% or less, preferably 1.3% or less, and more preferably 1.0% or less.

Zr : 0% or more and 1.5% or less

Zr is an arbitrary element of the alloy wire of the present invention. Zr is effective for precipitation hardening and strengthening thereof, and can be used as an alternative element of V or Mo. When it is desired to effectively exhibit such an effect of Zr, content of Zr is adjusted to more than 0%, Preferably it is 0.01% or more, More preferably, it is 0.02% or more. On the other hand, when the content of Zr is excessive, a decrease in aging hardening ability, a decrease in ductility, an increase in thermal expansion coefficient, and an increase in alloy wire cost occur. Therefore, the content of Zr is at most 1.5%, preferably at most 1.3%, more preferably at most 1.0%.

Hf : 0% or more and 1.5% or less

Hf is an arbitrary element of the alloy wire of the present invention. Hf is effective for precipitation hardening and strengthening thereof, and can be used as an alternative element of V or Mo. When it is desired to effectively exhibit such an effect of Hf, content of Hf is adjusted to more than 0%, Preferably it is 0.01% or more, More preferably, it is 0.02% or more. On the other hand, when the content of Hf is excessive, a decrease in aging hardening ability, a decrease in ductility, an increase in thermal expansion coefficient, and an increase in alloy wire cost occur. Therefore, the content of Hf is adjusted to 1.5% or less, preferably 1.4% or less, and more preferably 1.3% or less.

Ta : 0% or more and 1.5% or less

Ta is an arbitrary element of the alloy wire of the present invention. Ta is effective for precipitation hardening and strengthening thereof, and can be used as an alternative element of V or Mo. When it is desired to effectively exhibit such an effect of Ta, content of Ta is adjusted to more than 0%, Preferably it is 0.01% or more, More preferably, it is 0.02% or more. On the other hand, when Ta content is excessive, the fall of aging hardening ability, the fall of ductility, the increase of a thermal expansion coefficient, and the increase of alloy wire cost generate | occur | produce. Therefore, the content of Ta is adjusted to 1.5% or less, preferably 1.4% or less, and more preferably 1.3% or less.

W: 0% or more and 1.5% or less

W is an arbitrary element of the alloy wire of the present invention. W is effective for precipitation hardening and strengthening thereof, and can be used as an alternative element of V or Mo. When it is desired to effectively exert such effects of W, the content of W is adjusted to more than 0%, preferably 0.01% or more, more preferably 0.02% or more. On the other hand, when the content of W is excessive, a decrease in aging hardening ability, a decrease in ductility, an increase in thermal expansion coefficient, and an increase in alloy wire cost occur. Therefore, the content of W is adjusted to 1.5% or less, preferably 1.4% or less, and more preferably 1.3% or less.

Cu: 0% or more and 1.5% or less

Cu is an arbitrary element of the alloy wire of the present invention. Cu is effective for precipitation hardening and strengthening by Cu particle formation, and raises a Curie temperature. When it is desired to effectively exhibit such an effect of Cu, content of Cu is adjusted to more than 0%, Preferably it is 0.01% or more, More preferably, it is 0.02% or more. On the other hand, when Cu content is excess, the hot workability will fall and the alloy wire cost will increase. Therefore, content of Cu is 1.5% or less, Preferably it is 1.3% or less, More preferably, it adjusts to 1.0% or less.

O: 0% or more and 0.005% or less

O is an impurity of the alloy wire of the present invention. O lowers the ductility by oxide formation. Therefore, the content of O is adjusted to 0.005% or less, preferably 0.003% or less, and more preferably 0.001% or less.

N: 0% or more and 0.03% or less

N is an arbitrary element of the alloy wire of the present invention. N has the same effect as C, such as strengthening employment. When it is desired to effectively exhibit such an effect of N, content of N is adjusted to more than 0%, Preferably it is 0.01% or more. On the other hand, when N content is excess, ductility falls by nitride formation. Therefore, the content of N is adjusted to 0.03% or less, preferably 0.025% or less.

The alloy wire which concerns on one Embodiment of this invention contains 1 type, or 2 or more types of B: more than 0% and 0.05% or less, Ca: more than 0% and 0.05% or less, and Mg: more than 0% and 0.05% or less.

The alloy wire which concerns on other embodiment of this invention is more than Al: more than 0%, 1.5% or less, Ti: more than 0%, 1.5% or less, Nb: more than 0%, more than 1.5%, Zr: more than 0%, 1.5% or less, Hf: More than 0% and 1.5% or less, Ta: more than 0% and 1.5% or less, W: more than 0% and 1.5% or less, and Cu: more than 0% and 1.5% or less.

Organization of Alloy Ships

Hereinafter, the structure of the alloy wire of this invention is demonstrated.

The alloy wire of the present invention has a crystal grain in which (Mo, V) C-based composite carbide (hereinafter sometimes referred to as "composite carbide") containing both Mo and V exists inside.

When the amounts of Mo and V contained in the (Mo, V) C-based composite carbide are {Mo} and {V}, respectively, the value of {Mo} / {V} is 0.2 or more and 4.0 or less. When the value of {Mo} / {V} is less than 0.2, Mo-carbide carbides are formed, hardness and strength are lowered, and formation and growth of intragranular carbides occur quickly in aging heat treatment, and high hardness And the temperature range of the aging heat treatment which can maintain high intensity | strength becomes narrow, and high hardness and high strength are not obtained by the aging conditions of a wide temperature range. Therefore, the value of {Mo} / {V} is adjusted to 0.2 or more, preferably 0.3 or more, more preferably 0.4 or more. If the value of {Mo} / {V} is 0.2 or more, precipitation hardening and its strengthening can be optimized. On the other hand, when the value of {Mo} / {V} exceeds 4.0, V-deficient carbides are formed, the hardness and strength are lowered, and the formation and growth of intragranular carbides occurs quickly in aging heat treatment. The temperature range of the aging heat treatment which can maintain high strength becomes narrow, and high hardness and high strength are not obtained by the aging conditions of a wide temperature range. Therefore, the value of {Mo} / {V} is adjusted to 4.0 or less, preferably 3.7 or less, more preferably 3.4 or less. If the value of {Mo} / {V} is 4.0 or less, precipitation hardening and its reinforcement can be optimized.

The value of {Mo} / {V} is obtained as follows. The test piece is taken from the alloy wire, and the cross section of the test piece is polished. The composition of the carbide present inside the grains is analyzed using a transmission electron microscope (TEM) and an energy dispersive fluorescence X-ray analyzer (EDX). Specifically, the microstructure of the cross section of the polished test piece was observed using TEM, and the (Mo, V) C-based composite carbide present in the crystal grains was identified using EDX, and the (Mo, V) C-based The amount of Mo and V contained in the composite carbide is measured, and the value of {Mo} / {V} is obtained.

The density of the (Mo, V) C-based composite carbide in the crystal grains is preferably 10 pieces / µm ² or more. When the density of the (Mo, V) C-based composite carbide in the crystal grain is less than 10 / μm ² , there is a small amount of precipitates and there is a possibility that the composite carbide (Mo, V) C-based composite carbide in the crystal grain is low. If the density is 10 / micrometer ² or more, precipitation hardening and its strengthening can be optimized.

The ratio of the number of (Mo, V) C-based composite carbides having a diameter of 150 nm or less to the total number of (Mo, V) C-based composite carbides in a grain ((Mo, V) C-based composites having a diameter of 150 nm or less) The abundance of carbides) is preferably 50% or more, more preferably 70% or more, and still more preferably 90% or more. If the ratio of the number of (Mo, V) C-based composite carbides having a diameter of 150 nm or less to the total number of (Mo, V) C-based composite carbides in the grains is less than 50%, a number of coarse particles are formed. Although it may become low strength, if the ratio of the number of (Mo, V) C-based composite carbides having a diameter of 150 nm or less to the total number of (Mo, V) C-based composite carbides in the crystal grains is 50% or more, precipitation Curing and its strengthening can be optimized.

The density of the (Mo, V) C-based composite carbide in the crystal grains and the abundance of the (Mo, V) C-based composite carbide having a diameter of 150 nm or less are measured as follows using TEM and EDX. Using TEM, the microstructure of the cross section of the polished test piece was observed, and (Mo, V) C-based composite carbide present in the crystal grains was identified by electron beam diffraction and composition analysis using EDX. In addition, the total number of (Mo, V) C-based composite carbides was counted from the TEM bright field image observed and photographed at a magnification of 50 to 200,000 in accordance with the size of the carbides present in the crystal grains, and the diameter 150 existing in the TEM bright field image. The number of (Mo, V) C-based composite carbides of nm or less is counted. Based on the observed area of the TEM bright field image and the total number of (Mo, V) C-based composite carbides present in the bright field image, the density (pieces / μm ² ) of the (Mo, V) C-based composite carbide is determined. Then, based on the total number of (Mo, V) C-based composite carbides counted by the above method and the number of (Mo, V) C-based composite carbides having a diameter of 150 nm or less, the (Mo, V) C-based composite carbides The ratio of the number of (Mo, V) C-based composite carbides having a diameter of 150 nm or less to the total number (the abundance of (Mo, V) C-based composite carbides having a diameter of 150 nm or less) is obtained. The long diameter of the (Mo, V) C-based composite carbide (ie, the diameter of the circle circumscribed to the (Mo, V) C-based composite carbide) is set to the diameter of the (Mo, V) C-based composite carbide. do.

<Characteristics of Alloy Wires>

The tensile strength TS of the alloy wire of the present invention is preferably 1300 MPa or more, more preferably 1400 MPa or more, and even more preferably 1500 MPa or more. The elongation EL of the alloy wire of the present invention is preferably 0.8% or more, and more preferably 1.0% or more. TS and EL are measured by performing a tensile test according to JIS Z 2241 with respect to the test piece produced from the alloy wire.

The twist count value of the alloy wire of the present invention, which is measured at a distance between the gauge marks 100 times the final wire diameter of the alloy wire of the present invention, is preferably 20 or more times, more preferably 60 or more times. The measurement of the twist number value is carried out as follows. One end of the test piece produced from the alloy wire is fixed, the other end of the test piece is twisted, and the number of twists until the test piece breaks is measured as the number of twists. The distance between the gauges is 100xD (D represents the final wire diameter of the test piece), and the torsional speed is 60rpm. In addition, in this invention, a "line diameter" means the diameter of a circle when the cross section of a test piece causes, and the circle considerably diameter converted from the area of a cross section when the cross section of a test piece is not a circle. In addition, in this invention, a "circle equivalent diameter" means the diameter of the circle which has the same area as the cross-sectional area of a test piece.

The average linear thermal expansion coefficient between two points from 15 degreeC to 100 degreeC of the alloy wire of this invention becomes like this. Preferably it is 3.4x10 <^-6> / degrees C or less, More preferably, it is 3.0x10 <^-6> / degrees C or less. The average linear thermal expansion coefficient between two points from 15 degreeC to 230 degreeC of the alloy wire of this invention becomes like this. Preferably it is 4.4x10 <^-6> / degrees C or less, More preferably, it is 4.0x10 <^-6> / degrees C or less. The mean linear thermal expansion coefficient between two points from 100 degreeC to 240 degreeC of the alloy wire of this invention becomes like this. Preferably it is 4.4x10 <^-6> / degrees C or less, More preferably, it is 4.0x10 <^-6> / degrees C or less. The mean linear thermal expansion coefficient between two points from 230 degreeC to 290 degreeC of the alloy wire of this invention becomes like this. Preferably it is 11.4x10 <^-6> / degrees C or less, More preferably, it is 11.0x10 <^-6> / degrees C or less. The coefficient of linear thermal expansion is measured as follows. With a Forster tester (Formastor-EDP, manufactured by Fuji Denpa Goki Co., Ltd.), the displacement of the test piece during the temperature rising process is measured, and the average coefficient of thermal expansion between two points from 15 ° C to 100 ° C, and 15 ° C to 230 ° C. The average linear thermal expansion coefficient between two points, the average linear thermal expansion coefficient between two points from 100 degreeC to 240 degreeC, and the average linear thermal expansion coefficient between two points from 230 degreeC to 290 degreeC are measured.

<Form of Alloy Wire>

The form of the alloy wire of the present invention is not particularly limited as long as it is linear. As an aspect of the alloy wire of this invention, a ring wire, a flat wire, a square wire, etc. are mentioned, for example. Although the wire diameter of the alloy wire of this invention is not specifically limited, For example, it is 2.0-3.8 mm. In addition, the meaning of a "wire diameter" is as above-mentioned.

<Method for producing alloy wire>

The alloy wire of this invention can be manufactured by the following method, for example. The steel having the alloy composition of the present invention is melted, a steel ingot or a bloom is produced by ingot or continuous casting, and then hot forged or hot rolled for the purpose of round bars and shell materials. It is molded into steel having a shape to be. Thereafter, the alloy wire of the present invention can be produced by sequentially performing solution treatment, wire drawing, and aging heat treatment on the steel. For example, the solution treatment can be performed at a heating temperature of 1200 ° C. and a heating time of 30 minutes. In addition, the solution treatment can be abbreviate | omitted if a rapid cooling, such as water cooling, is performed immediately after a steel material manufacturing process in hot forging or hot rolling. Aging heat treatment can be performed, for example by heating temperature of 625 degreeC, and heating time for 2 hours. It is preferable to cold-process steel materials after a solution treatment and before aging heat treatment.

The alloy wire having the alloy composition of the present invention has a wide range of conditions (temperature and holding time of this temperature) of aging heat treatment at which high hardness is obtained. Therefore, when giving hardness by aging heat treatment, the hardness fall due to the change of manufacturing conditions (for example, material, heating temperature, heating time, etc.), a control failure, etc. can be avoided. In addition, in the aging heat treatment, even if excessive heat treatment is performed, a significant decrease in hardness due to excessive heat treatment can be avoided. Such stability is an effect caused by precipitation of (Mo, V) C-based composite carbide having a value of {Mo} / {V} of 0.2 or more and 4.0 or less in crystal grains in aging heat treatment.

<Coated alloy wire>

The coated alloy wire of the present invention includes the alloy wire of the present invention and an Al coating layer (Al coating) or Zn coating layer (Zn coating) formed on the surface of the alloy wire of the present invention. In addition to the effect similar to the alloy wire of this invention, the coating alloy wire of this invention has corrosion resistance resulting from an Al coating layer or a Zn coating layer. The Al coating layer can be formed, for example, by a known method such as conform extrusion. A Zn coating layer can be formed by well-known methods, such as a plating process, for example.

EXAMPLE

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail based on an Example.

50 kg of alloys having the component compositions shown in Tables 1 (Invention Examples No. 1 to 30) and Table 2 (Comparative Examples No. 31 to 55) were dissolved in a vacuum induction furnace (VIM) to obtain an ingot. This ingot was heated at 1200 degreeC for 1 hour, and was extended by the steel bar of diameter 20mm. About this steel bar, the solution treatment was performed on conditions of the heating temperature of 1200 degreeC, and heating time for 30 minutes. The bar steel after the solution treatment was turned to 15 mm in diameter, and then wire drawing was performed at room temperature to produce an alloy wire having a wire diameter of 8 mm. In Tables 1 and 2, [Mo], [V], and [C] represent the amounts of Mo, V, and C contained in the alloy, respectively.

TABLE 1

TABLE 2

※ Underline is outside the scope of the present invention

[Evaluation of Carbide in Grain after Aging Heat Treatment]

The test piece (length 10mm) produced from the alloy wire of 8 mm of wire diameters was aging-treated on the conditions of the heating temperature of 500-1000 degreeC, and 30 minutes-24 hours of heating time.

The composition of the carbide present in the crystal grains was analyzed using a transmission electron microscope (TEM) and an energy dispersive fluorescence X-ray analyzer (EDX). Analysis by TEM and EDX was performed as follows. Using TEM, the microstructure of the cross section of the polished test piece was observed, and EDX was used to identify (Mo, V) C-based composite carbides present in the grains, and included in (Mo, V) C-based composite carbides. The amount of Mo and V to be measured was measured, and the value of {Mo} / {V} was obtained. The results are shown in Table 3 (Inventive Examples No. 1 to 30) and Table 4 (Comparative Examples No. 31 to 55). In Tables 3 and 4, {Mo} and {V} represent the amounts of Mo and V contained in the (Mo, V) C-based composite carbide, respectively.

With respect to the test piece after aging heat treatment, the density of the (Mo, V) C-based composite carbide present in the crystal grains was analyzed using TEM and EDX. Analysis by TEM and EDX was performed as follows. Using TEM, the microstructure of the cross section of the polished test piece was observed, and (Mo, V) C-based composite carbide present in the crystal grains was identified by electron beam diffraction and composition analysis using EDX. Then, the amounts of Mo and V contained in the (Mo, V) C-based composite carbide were measured, and the value of {Mo} / {V} was obtained. The value of {Mo} / {V} of the composite carbide aimed by this invention is 0.2-4.0. For quantification of the dispersed state, it was observed at a magnification of 500,000 to 200,000 in accordance with the size of the carbide present in the crystal grains, and the total number of (Mo, V) C-based composite carbides was counted from the photographed TEM bright field image, and the same TEM was specified. The number of (Mo, V) C-based composite carbides having a diameter of 150 nm or less existing in the night phase was counted. Based on the observed area of the TEM bright field image and the total number of (Mo, V) C-based composite carbides present in the same TEM bright field image, the density of the (Mo, V) C-based composite carbide (piece / μm ² ) is obtained. It was. Then, based on the total number of (Mo, V) C-based composite carbides counted by the above method and the number of (Mo, V) C-based composite carbides having a diameter of 150 nm or less, the (Mo, V) C-based composite carbides The ratio of the number of (Mo, V) C-based composite carbides having a diameter of 150 nm or less to the total number (the abundance of (Mo, V) C-based composite carbides having a diameter of 150 nm or less) was determined. The long diameter of the (Mo, V) C-based composite carbide (ie, the diameter of the circle circumscribed to the (Mo, V) C-based composite carbide) was taken as the diameter of the (Mo, V) C-based composite carbide. The value of {Mo} / {V} of the (Mo, V) C-based composite carbide satisfies 0.2 to 4.0, and has a density of 10 or more μm ² or more and a diameter of 150 nm or less (Mo, V) C When the abundance of the system complex carbide is 50% or more, "A: the target complex carbide exists and the dispersion state is good", and the value of {Mo} / {V} of the (Mo, V) C complex carbide is When the density is less than 10 / μm ² or the presence rate of (Mo, V) C-based composite carbides having a diameter of 150 nm or less is less than 50%, “B: The target composite carbide exists. However, the dispersion state was "bad" and the case where the value of {Mo} / {V} of the (Mo, V) C-based composite carbide did not satisfy 0.2 to 4.0 was evaluated as "F: composite carbide defect". Evaluation F falls outside the scope of the present invention. The results are shown in Table 3 (Inventive Examples No. 1 to 30) and Table 4 (Comparative Examples No. 31 to 55).

TABLE 3

TABLE 4

※ Underline is outside the scope of the present invention

[Evaluation of Thermal Aging Stability]

About the test piece (length 100mm) produced from the alloy wire of 8 mm of wire diameters, heating time was fixed to 6 hours, and the aging heat treatment was performed by changing heating temperature between 610-650 degreeC. About the test piece before an aging treatment and after an aging heat treatment, the JIS14A test piece was produced by machining, the tensile test was performed according to JIS Z 2241 using the tensile tester (100kN universal tester, Shimadzu Corporation), and tensile strength (TS) was measured. A curve was prepared in which the horizontal axis was the aging temperature and the vertical axis was the tensile strength (see Fig. 1). Based on this curve, a temperature range was obtained in which a tensile strength of 96% or more of the maximum tensile strength (MAX 6hr) was secured. . `` A: Good thermal aging stability '' for the temperature range where the tensile strength of 96% or more of the maximum tensile strength (MAX 6hr) is 30 ° C or more, and `` F: Poor thermal aging stability '' for the case below 30 ° C Evaluated. The results are shown in Table 5 (Inventive Examples No. 1 to 30) and Table 6 (Comparative Examples No. 31 to 55). 1 is an example of a curve in which the horizontal axis is the aging temperature and the vertical axis is the tensile strength when the heating time is fixed at 6 hours and the heating temperature is changed between 610 to 650 ° C. to perform the aging heat treatment. In this curve, the temperature range which can ensure the tensile strength of 96% or more of the maximum tensile strength (MAX 6hr) is 32 degreeC.

[Evaluation of aging stability over time]

The heating temperature was fixed at 650 degreeC with respect to the test piece (length 100mm) produced from the alloy wire of 8 mm of wire diameters, and the aging heat treatment was performed by changing heating time between 30 minutes-9 hours. About the test piece before an aging treatment and after an aging heat treatment, the JIS14A test piece was produced by machining, the tensile test was performed according to JIS Z 2241 using the tensile tester (500 kN universal tester, the Shimadzu Corporation make), and tensile strength (TS) was measured. A curve is created with the aging temperature on the horizontal axis and the tensile strength on the vertical axis (see FIG. 2). Based on this curve, a time range in which a tensile strength of 97% or more of the maximum tensile strength (MAX 650 ° C) can be obtained is obtained. It was. When the time range where the tensile strength of 97% or more of the maximum tensile strength (MAX 650 ° C.) can be secured is 3 hours or more, “A: Good age stability is good”, and when less than 3 hours, “F: Time age stability is good. This defect was evaluated. The results are shown in Table 5 (Inventive Examples No. 1 to 30) and Table 6 (Comparative Examples No. 31 to 55). 2 is an example of a curve in which the horizontal axis is the aging temperature and the vertical axis is the tensile strength when the heating temperature is fixed at 650 ° C. and the heating time is changed between 30 minutes to 9 hours to perform the aging heat treatment. In this curve, the time range where the tensile strength of 97% or more of the maximum tensile strength (MAX 650 ° C) can be secured is 3.8 hours.

When both the thermal aging stability evaluation and the aging stability over time were evaluated as A, the following evaluation was performed, but when either one was evaluated as F, the following evaluation was not performed.

[Evaluation of Tensile Properties After Aging Treatment]

Aging heat treatment was performed on the test piece (length 300mm) produced from the alloy wire of 8 mm of wire diameters on the conditions of 500-1000 degreeC of heating temperature, and 30 minutes-24 hours of heating time. With respect to the test piece after the aging treatment, new acid processing was performed at room temperature to produce a test piece (length 400 mm or more) having a line diameter of 3.1 mm. Tensile test pieces having a wire diameter of 3.1 mm and a gauge length of 250 mm were subjected to a tensile test at a stroke speed of 20 mm / min or less at room temperature using a tensile tester (100 kN universal testing machine, manufactured by Shimadzu Corporation). Strength (TS) and elongation (EL) were measured. When TS is 1500 MPa or more and EL is 0.8% or more, "A: Tensile property is very good", TS is less than 1500 MPa, 1400 MPa or more, and when EL is 0.8% or more, "B: Good tensile property", TS Was less than 1400 MPa, 1300 MPa or more, and EL was 0.8% or more. "C: Tensile properties were good", TS was less than 1300 MPa, or EL was less than 0.8% were evaluated as "F: poor tensile properties." . The results are shown in Table 5 (Inventive Examples No. 1 to 30) and Table 6 (Comparative Examples No. 31 to 55). Here, the following evaluation was performed when it evaluated by A, B, or C, but the following evaluation was not performed when it evaluated by F here.

[Evaluation of Torsion Count Value After Aging Heat Treatment]

The twist count value of the test piece (length 310 mm) of the wire diameter 3.1 mm produced similarly to the above was measured. The measurement of the twist number value was performed as follows. One end of the test piece was fixed, the other end of the test piece was twisted, and the number of twists until the test piece broke was measured as the number of twists. The distance between the gauges was 100D (D represents the final wire diameter of the test piece), and the torsional speed was 60 rpm. When the number of times of twisting is 60 or more, "A: Number of times of twisting is extremely good", and when the number of times of twisting is 20 to 59 times, "B: The number of times of twisting is good" and the number of times of twisting is less than 20 times. F: torsion count value was bad ”. The results are shown in Table 5 (Inventive Examples No. 1 to 30) and Table 6 (Comparative Examples No. 31 to 55). Here, the following evaluation was performed when it evaluated by A or B, but the following evaluation was not performed when it evaluated by F here.

[Evaluation of Linear Thermal Expansion Coefficient after Aging Heat Treatment]

The linear thermal expansion coefficient of the test piece of the wire diameter of 3.1 mm produced in the same manner to the above was measured. The coefficient of linear thermal expansion was measured as follows. With a Forster tester (Formastor-EDP, manufactured by Fuji Denpa Goki Co., Ltd.), the displacement of the test piece during the temperature rising process is measured, and the average coefficient of thermal expansion between two points from 15 ° C to 100 ° C, from 15 ° C to 230 ° C. The average coefficient of linear expansion between two points of, the average coefficient of linear expansion between two points from 100 ° C to 240 ° C, and the average coefficient of linear expansion between two points from 230 ° C to 290 ° C were measured. When the average coefficient of linear expansion between two points from 15 ° C to 100 ° C is 3.0 × 10 ⁻⁶ / ° C. or less, “A: The coefficient of linear thermal expansion is extremely low”, exceeding 3.0 × 10 ⁻⁶ / ° C. and 3.5 × 10 ^-6 / ℃ to less than "B: the coefficient of linear thermal expansion low", the it not less than 3.5 × 10 ^-6 / ℃: was evaluated as "F high linear thermal expansion coefficient." In the case where the average coefficient of linear thermal expansion between two points from 15 ° C to 230 ° C is 4.0 × 10 ⁻⁶ / ° C. or less, “A: The coefficient of linear thermal expansion is extremely low” exceeds 4.0 × 10 ⁻⁶ / ° C. The case where it was less than ^4.5x10 <^-6> / degreeC was evaluated as "B: low linear thermal expansion coefficient", and the case where it was ^{4.5x10 <-6>} / degreeC or more as "F: high linear thermal expansion coefficient." In the case where the average coefficient of linear expansion between two points from 100 ° C to 240 ° C is 4.0 × 10 ⁻⁶ / ° C. or less, “A: The coefficient of linear thermal expansion is extremely low” exceeds 4.0 × 10 ⁻⁶ / ° C. The case where it was less than ^4.5x10 <^-6> / degreeC was evaluated as "B: low linear thermal expansion coefficient", and the case where it was ^{4.5x10 <-6>} / degreeC or more as "F: high linear thermal expansion coefficient." In addition, when the average coefficient of linear thermal expansion between two points from 230 ° C to 290 ° C is 11.0 × 10 ⁻⁶ / ° C. or less, “A: The coefficient of linear thermal expansion is extremely low” exceeds 11.0 × 10 ⁻⁶ / ° C. The case where it was less than ^11.5x10 <^-6> / degreeC was evaluated as "B: low linear thermal expansion coefficient", and the case where it was ^{11.5x10 <-6>} / degreeC or more as "F: high linear thermal expansion coefficient." From the result of having measured and evaluated the above four temperature ranges, comprehensive evaluation of the linear thermal expansion coefficient of each test piece was further performed. In evaluation of the average linear thermal expansion coefficient of 15 degreeC-230 degreeC, the average linear thermal expansion coefficient of 100 degreeC-240 degreeC, and the average linear thermal expansion coefficient of 15 degreeC-290 degreeC, all A evaluation or B evaluation is one after Comprehensive evaluation when three are A evaluation is "A: Extremely low coefficient of linear thermal expansion", Comprehensive evaluation when two B evaluations are two and A evaluation is "B: Low linear expansion coefficient", 1 The dog is A evaluation, and the comprehensive evaluation when the following three are B evaluation evaluates as "C: linear expansion coefficient is substantially low", and the comprehensive evaluation when F evaluation is one or more is evaluated as "F: high linear expansion coefficient". It was. The results are shown in Table 5 (Inventive Examples No. 1 to 30) and Table 6 (Comparative Examples No. 31 to 55).

In Comparative Examples No. 49 and No. 50, the B and Mg were excessive, respectively, the hot workability was poor, and a large number of cracks occurred at the time of forging. Therefore, the evaluation test pieces could not be produced. Therefore, various evaluations were not performed. .

TABLE 5

TABLE 6

Inventive Examples Nos. 1 to 26 are

Condition a: to satisfy the alloy composition of the present invention,

Condition b: (Mo, V) C-based composite carbides present in the grains,

Condition c: the value of ([Mo] +2.8 [V]) / [C] is from 9.6 to 21.7,

Condition d: the value of {Mo} / {V} is 0.2 or more and 4.0 or less,

Condition e: In the crystal grains, the density of the (Mo, V) C-based composite carbide was 10 / μm ² or more, and (Mo, V) C-based composite carbides having a diameter of 150 nm or less with respect to the total number of (Mo, V) C-based composite carbides. V) the proportion of the number of C-based composite carbides is 50% or more;

Condition f: When the content of Cr is more than 0%, the value of ([Mo] + [V]) / [Cr] is 1.2 or more,

Condition g: when the content of Co is more than 0%, [Co] + [Ni] is 35% or more and 40% or less,

All of them were satisfied, and all of the characteristics required as the high strength low thermal expansion alloy wire were A or B evaluations, that is, they had high strength, high twist count value, good ductility, and low thermal expansion rate. In addition, Examples 1 to 26 of the present invention were excellent in aging stability (thermal aging stability and aging stability over time).

In addition, Examples No. 27 to No. 30 of the present invention satisfy all of the conditions a to d, and are substantially superior in abrasion resistance, high strength, good ductility, low thermal expansion rate, and aging stability (thermal aging stability and aging stability over time). And C evaluation which is somewhat inferior to B evaluation in any one, without satisfy | filling any 1 type of conditions e-g.

On the other hand, Comparative Examples No. 31 to No. 55 do not satisfy any one or more of the conditions a to d, and at least one of strength, torsion characteristics, ductility, thermal expansion rate, and aging stability (thermal aging stability and aging stability over time). Either one was F evaluation and lacked the required characteristic.

Claims (12)

In mass%,
C: 0.1% or more and 0.4% or less,
Si: 0.1% or more and 2.0% or less,
Mn: greater than 0% and less than 2.0%,
Ni: 25% or more and 40% or less,
V: 0.5% or more and 3.0% or less,
Mo: 0.4% or more and 1.9% or less,
Cr: 0% or more and 3.0% or less,
Co: 0% or more and 3.0% or less,
B: 0% or more and 0.05% or less,
Ca: 0% or more and 0.05% or less,
Mg: 0% or more and 0.05% or less,
Al: 0% or more and 1.5% or less,
Ti: 0% or more and 1.5% or less,
Nb: 0% or more and 1.5% or less,
Zr: 0% or more and 1.5% or less,
Hf: 0% or more and 1.5% or less,
Ta: 0% or more and 1.5% or less,
W: 0% or more and 1.5% or less,
Cu: 0% or more and 1.5% or less,
O: 0% or more and 0.005% or less, and
N: 0% or more and 0.03% or less
A high-strength low thermal expansion alloy wire containing a balance, the balance being made of Fe and unavoidable impurities,
In the crystal grains of the alloy wire, (Mo, V) C-based composite carbide containing both Mo and V is present,
When the amounts of Mo, V, and C contained in the alloy wire are [Mo], [V], and [C], respectively, the value of ([Mo] +2.8 [V]) / [C] is 9.6 or more 21.7 Is less than
When the amounts of Mo and V contained in the (Mo, V) C-based composite carbide are {Mo} and {V}, respectively, the value of {Mo} / {V} is 0.2 or more and 4.0 or less,
High strength low thermal expansion alloy wire. The method of claim 1,
In the crystal grains, the (Mo, V) C-based composite carbide has a density of 10 / μm ² or more, and the (Mo, V) C-based composite carbide having a diameter of 150 nm or less with respect to the total number of ( Mo, V) The high strength low thermal expansion alloy wire whose ratio of the number of C type composite carbides is 50% or more. The method according to claim 1 or 2,
In mass%, containing Cr: more than 0% and not more than 3.0%,
When the amounts of Mo, V, and Cr contained in the alloy wire are [Mo], [V], and [Cr], respectively, the value of ([Mo] + [V]) / [Cr] is 1.2 or more, high strength Low thermal expansion alloy wire. The method according to any one of claims 1 to 3,
By mass%, Co: contains more than 0% and 3.0% or less,
The high strength low thermal expansion alloy wire whose [Co] + [Ni] is 35% or more and 40% or less when the quantity of Co and Ni contained in the said alloy wire is [Co] and [Ni], respectively. The method according to any one of claims 1 to 4,
The high-strength low thermal expansion alloy wire which contains 1 type (s) or 2 or more types of B: more than 0% and 0.05% or less, Ca: more than 0% and 0.05% or less, and Mg: more than 0% and 0.05% or less. The method according to any one of claims 1 to 5,
By mass%, Al: greater than 0% and 1.5% or less, Ti: greater than 0% and 1.5% or less, Nb: greater than 0% and 1.5% or less, Zr: greater than 0% and 1.5% or less, Hf: greater than 0% and 1.5% or less, Ta : High strength low thermal expansion alloy wire containing 1 type (s) or 2 or more types more than 0% and 1.5% or less, W: more than 0% and 1.5% or less, and Cu: more than 0% and 1.5% or less. The method according to any one of claims 1 to 6,
High strength low thermal expansion alloy wire containing, in mass%, N: more than 0% and 0.03% or less. The method according to any one of claims 1 to 7,
A high strength low thermal expansion alloy wire having a tensile strength of 1400 MPa or more. The method according to any one of claims 1 to 8,
A high-strength low thermal expansion alloy wire having a twist count value of 20 or more times measured at a distance between the gauge marks 100 times the final wire diameter of the alloy wire. The method according to any one of claims 1 to 9,
High strength low thermal expansion alloy wire, elongation is more than 0.8%. The method according to any one of claims 1 to 10,
The average coefficient of linear expansion between two points from 15 ° C to 100 ° C is 3 × 10 ^-6 / ° C or less (15 to 100 ° C), and the average coefficient of linear expansion between two points from 15 ° C to 230 ° C is 4 × 10 ^-6 / ° C or less (15 to 230 ° C), average linear thermal expansion coefficient between 2 points from 100 ° C to 240 ° C is 4 × 10 ^-6 / ° C or less (100 to 240 ° C), and 230 ° C The high-strength low thermal expansion alloy wire whose average coefficient of linear thermal expansion between two points from -290 degreeC to 290 degreeC is 11 * 10 <^-6> / degreeC or less (230-290 degreeC). The high strength low thermal expansion coating alloy wire containing the high strength low thermal expansion alloy wire of any one of Claims 1-11, and the Al coating layer or Zn coating layer formed on the surface of the said high strength low thermal expansion alloy wire.

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