JPH09241669A - Lubricant for plastic working of metallic materials - Google Patents

Abstract

(57) Abstract: To provide a lubricating oil for plastic working of a metal material, which has excellent formability, degreasing property and weldability. SOLUTION: Lubricating oil has a content C ₁ of 20% by weight ≦ C ₁
≦ 60% by weight of the first component and C ₂ content of 2% by weight ≦
It comprises a second component with C ₂ ≦ 10% by weight and the remaining third component, and has a kinematic viscosity V _{1 at} 40 ° C. of V ₁ ≦
The mixture is 15 cSt. First component has carbon number N ₁
Is at least one of unsaturated fatty acid methyl ester and unsaturated fatty acid ethyl ester with 16 ≦ N ₁ ≦ 18. The second component is at least one of an oil-soluble polyacrylic acid alkyl ester and an oil-soluble polymethacrylic acid alkyl ester in which the carbon number N ₂ of the alkyl group is N ₂ ≦ 18. The third component is a hydrocarbon oil having compatibility with the first and second components and having a boiling point Bp of 250 ° C. ≦ Bp ≦ 310 ° C. Such a lubricating oil has a low viscosity,
It is almost liquid.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lubricating oil for plastic working of metal materials, and more particularly to a lubricating oil suitable for press forming a high strength Al alloy plate.

[0002]

2. Description of the Related Art At present, a high-strength Al alloy plate is used as a constituent material of press-formed parts for the purpose of weight reduction of vehicles. In this case, since the forming limit of the high-strength Al alloy plate is lower than that of the steel plate by about 30%, a solid film type lubricant is applied to the high-strength Al alloy plate in order to improve its formability. Wax type lubricants and resin type lubricants are known as the solid film type lubricants.

[0003]

However, the conventional solid film type lubricant has the following problems.

(1) Since a coating process by a roll coater or electrostatic coating and a drying process are indispensable for forming a solid film, workability of forming the solid film is poor.

(2) A part of the solid film is easily peeled off due to collision with another substance and blocking, and the solid film has no self-repairing ability, which causes poor lubrication.

(3) Generally, prior to press molding,
The high-strength Al alloy plate is subjected to leveler cleaning to remove foreign matters such as dust. However, when a solid film is formed on the high-strength Al alloy plate, the solid film may fall off, so Unable to perform leveler cleaning. Therefore, great care must be taken in the storage of the Al alloy plate having a solid film.

If press molding is performed with foreign matter such as dust adhering to the surface of the solid film, traces of foreign matter such as dust will be generated on the surface of the press-molded component, so the surface of the press-molded component must be buffed. I have to.

(4) The thickness of the solid coating is likely to vary, and as a result, the electrical resistance value increases in the thick portion of the solid coating, leading to poor welding and removal of the solid coating by immersion in the degreasing liquid. May not be performed uniformly over the entire surface, that is, degreasing failure may occur, and uneven coating thickness may remain as a trace on the surface of the press-molded component.

[0009]

The present invention exhibits excellent moldability equal to or higher than that of a solid film type lubricant,
Further, the workability of forming an oil film is excellent, and welding defects and degreasing defects do not occur even if the thickness of the oil film is not strictly controlled. Furthermore, the plastic working lubricating oil that can be used as a leveler cleaning liquid is provided. The purpose is to do.

According to the present invention to achieve the above object,
A first component having a content C ₁ of 20% by weight ≤C ₁ ≤60% by weight, a second component having a content C ₂ of 2% by weight ≤C ₂ ≤10% by weight, and a balance of a third component And 40 ℃
In which the kinematic viscosity V ₁ is V ₁ ≦ 15 cSt, and the first component has a carbon number N ₁ of 16 ≦ N ₁ ≦ 22.
At least one of unsaturated fatty acid methyl ester and unsaturated fatty acid ethyl ester, and the second component is an oil-soluble polyacrylic acid alkyl ester or an oil-soluble polymethacrylic acid alkyl ester in which the carbon number N ₂ of the alkyl group is N ₂ ≦ 18. A metal material, which is at least one kind of ester, wherein the third component is compatible with the first and second components, and is a hydrocarbon oil having a boiling point Bp of 250 ° C. ≦ Bp ≦ 310 ° C. A lubricating oil for plastic working is provided.

As described above, the lubricating oil having the specified first to third components and their contents has a low viscosity and is substantially liquid. In this lubricating oil, the first component functions as an oiliness improver, and during plastic working, a tool and a metal material,
For example, the frictional force between the high-strength Al alloy plates is reduced and seizure is prevented. The second component also has the effect of preventing oil film breakage. Furthermore, the third component has a diluting effect of reducing the kinematic viscosity of the first and second components.

Therefore, in forming the oil film, brushing, spray coating or the like can be adopted to improve the workability of forming the oil film. Further, since the lubricating oil has a kinematic viscosity V ₁ of V ₁ ≤15 cSt, it can be used as a leveler cleaning liquid. In this case, after cleaning, for example, an oil film remains on the surface of the high-strength Al alloy plate. Therefore, the forming work is unnecessary. Further, the oil film exhibits excellent moldability and also has good degreasing property. Moreover, the change in the thickness of the oil film does not adversely affect the weldability, the degreasing property, and the surface quality of the molded product made of, for example, an Al alloy in practice, so that the thickness control is easy. is there.

However, in the lubricating oil, its kinematic viscosity V ₁
When (40 ° C.) is V ₁ > 15 cSt, the oil film thickness increases and the degreasing property and weldability deteriorate.

In the first component, the content C ₁ is C ₁ <
At 20% by weight, the moldability is not sufficient, while C ₁ > 60
If the content is wt%, the weldability will deteriorate. In addition, the carbon number N ₁ is N ₁
When <16, the formability is not sufficient, while when N ₁ > 18, the melting point of the first component, and thus the viscosity, becomes high, and the handleability and weldability deteriorate.

In the second component, the content C ₂ is C ₂ <
If it is 2% by weight, the moldability is not sufficient. On the other hand, if C ₂ > 10% by weight, the kinematic viscosity V ₁ ≦ 15 cSt (40 ° C.) cannot be achieved and the degreasing property is deteriorated. Further, when the carbon number N _{2 of the} alkyl group is N ₂ > 18, the viscosity of the second component becomes high, and the compatibility with the first and third components decreases.

In the third component, that is, the hydrocarbon oil, when the boiling point Bp is Bp <250 ° C., the hydrocarbon oil is gradually volatilized at room temperature and normal pressure and the residue is concentrated, so that the weldability and degreasing property are deteriorated. On the other hand, Bp> 310
At ℃, the viscosity of hydrocarbon oil becomes high, so its diluting effect is lost.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION In the first component, methyl oleate, methyl palmitoleate and the like correspond to unsaturated fatty acid methyl ester having carbon number N ₁ of 16 ≦ N ₁ ≦ 18. Further, ethyl oleate, ethyl palmitoleate and the like correspond to unsaturated fatty acid ethyl ester having carbon number N ₁ of 16 ≦ N ₁ ≦ 18 as described above.

The unsaturated fatty acid methyl ester and the unsaturated fatty acid ethyl ester are used alone or as a mixture thereof. In this case, the unsaturated fatty acid methyl ester itself and the unsaturated fatty acid ethyl ester themselves may each be a mixture.

In the second component, its molecular weight M is preferably
Actually, 1 × 10^Four≦ M ≦ 3 × 10 ^FiveIt is. M <1 ×
10^FourMay be less effective as a lubricating oil component
, While M> 3 × 10^FiveThen the viscosity increases and the
The handling and degreasing properties may decrease.
You.

Examples of the alkyl polyacrylate include polymethyl acrylate, polyethyl acrylate, polybutyl acrylate, 2-ethyl-hexyl polyacrylate, octyl polyacrylate, dodecyl polyacrylate, stearyl polyacrylate and the like. Applicable

The polymethacrylic acid alkyl ester includes
Examples thereof include polymethyl methacrylate, polybutyl methacrylate, poly (2-ethylhexyl methacrylate), isooctyl polymethacrylate, dodecyl polymethacrylate, and stearyl polymethacrylate.

The polyacrylic acid alkyl ester and the polymethacrylic acid alkyl ester are used alone or as a mixture thereof. In this case, the polyacrylic acid alkyl ester itself and the polymethacrylic acid alkyl ester themselves may be a mixture.

The third component hydrocarbon oil is a mineral oil,
At least one of isoparaffins, olefins and n-α-olefins (where the unsaturated bond is in the α-position) corresponds.

Hereinafter, specific examples will be described.

As the first component, methyl oleate and ethyl palmitoleate, as the second component, poly (2-ethylmethacrylate) -hexyl and stearyl polyacrylate, and as the third component, isoparaffin and C having 16 carbon atoms. ₁₆ n-α olefins were prepared.

Lubricating oils Examples 1 to 16 were prepared by mixing the first to third components in respective predetermined amounts. Table 1 shows the compositions of Examples 1 to 16 and the kinematic viscosity V _{1 at} 40 ° C.
Is shown.

[0027]

[Table 1]

Lubricating oils of Comparative Examples 1 to 5 were prepared by selectively using the first to third components and mixing them in predetermined contents. Table 2 shows the compositions of Comparative Examples 1 to 5 and the kinematic viscosity V ₁ at 40 ° C. In addition, in Table 2, as Comparative Example 6, a commercially available X coat (manufactured by Nippon Steel Corporation, trade name, wax-based lubricant) is also listed.

[0029]

[Table 2]

Next, Examples 1 to 16 and Comparative Examples 1 to 5
Were used to examine their formability, weldability and degreasing property.

Various evaluation test methods are as follows.

(1) Formability Using a test material having an oil film, deep drawing was carried out by a cylindrical deep drawing tester, and a portion of the test material corresponding to a rounded portion (so-called rounded portion) on the outer circumference of the punch bottom was broken. I determined the aperture depth to do. Therefore, it is evaluated that the deeper the drawing depth, the better the formability.

The test conditions are as follows. Test material: 1.0 mm thick, 86 mm diameter high-strength Al alloy plate (JIS
5182-O mill material); Formation of oil film: Lubricant oil is brush-coated on both surfaces of the test material so as to be approximately uniformly 2 g / m ² ; Die: Die hole diameter 42.58 mm, die shoulder radius 9. 0 mm; punch: diameter 40.0 mm, round radius of punch bottom outer circumference 4.5 mm; punch speed: 20 m / min; wrinkle holding force: 1000 kg. (2) Weldability MIG (MIG) welding was performed using a test material having an oil film, and the quality of the appearance of the weld, that is, the stability of the bead and the presence of blowholes in the weld were examined.

The test conditions are as follows. Test material: high-strength Al alloy plate (JIS 5182-O mill material) having a thickness of 2.5 mm, a length of 250 mm, and a width of 150 mm; formation of an oil film: lubricating oil on both sides of the test material is approximately 2 g / m ² respectively. So as to be applied; power setting: 140A, 23V; welding wire: Al alloy wire (JIS A5356W
Y), diameter 1.2 mm; welding speed: 100 cm / min; advance angle: 5 degrees; distance between torches: 10 mm. (3) Degreasing property The test material having an oil film was immersed in a degreasing liquid, and then the water wetting rate of the test material was determined. Therefore, the higher the water wetting rate, the better the degreasing property. The test conditions are as follows. Test material: thickness 1.0mm, length 200m
High strength Al alloy plate with m and width of 100 mm (JIS 5182
-O-mill material); Oil film formation: Lubricating oil is brushed on both sides of the test material so as to become approximately 2 g / m ² respectively; Degreasing liquid: Surf Cleaner 53s (trade name, manufactured by Nippon Paint Co., Ltd.) 0.5 wt% solution, solution temperature 45 ° C. (constant); Immersion time: 2 minutes. In the case of Comparative Example 6, this was brush-coated on both sides of the same test material as described above, and then dried to form a solid film. Various evaluation test methods and other test conditions for this are the same as described above.

Table 3 shows the results of various evaluation tests.

[0036]

[Table 3]

As is clear from Table 3, Examples 1 to 16
It is found that has excellent moldability, degreasing property and weldability. In Examples 1 to 16, it was found that there are some differences in formability, degreasing property, and weldability depending on the thickness of the oil film, but there is no practical problem.

In Comparative Example 1, the content C ₁ of the first component was C ₁ <2.
Since it is 0% by weight, the moldability is poor and the kinematic viscosity is V ₁
The degreasing property also tends to decrease due to the slightly high value.

In Comparative Example 2, the content C ₁ of the first component is C ₁ > 6.
Since it is 0% by weight, the weldability deteriorates and the kinematic viscosity V
_{Since 1} is V ₁ > 15 cSt, the degreasing property is low.

In Comparative Example 3, the content C ₁ of the first component was C ₁ <2.
Since it is 0% by weight, the moldability is poor and the kinematic viscosity is V ₁
The degreasing property also tends to decrease due to the slightly high value.

In Comparative Example 4, the content C ₁ of the first component is C ₁ > 6.
Since it is 0% by weight, the weldability deteriorates and the kinematic viscosity V
_{Since 1} is V ₁ > 15 cSt, the degreasing property is low.

In Comparative Example 5, the content C ₁ of the first component is C ₁ > 6.
Since it is 0% by weight, weldability is deteriorated, and since the content C ₂ of the second component is C ₂ <2% by weight (C ₂ = 0% by weight), moldability is also deteriorated.

Since Comparative Example 6 forms a solid film,
The forming work is poor, and the degreasing property and the weldability are deteriorated due to the variation in the thickness of the solid film.

The present invention is not limited to the above embodiment.

[0045]

EFFECTS OF THE INVENTION According to the present invention, by virtue of the above-mentioned constitution, the workability of forming an oil film is good, the moldability, the degreasing property and the weldability are excellent, and the plasticity which can be used as a leveler cleaning liquid is obtained. A lubricating oil for processing can be provided.

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[Procedure amendment]

[Submission date] February 6, 1997

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0036

[Correction method] Change

[Correction contents]

[0036]

[Table 3]

Continuation of front page (51) Int.Cl. ⁶ Identification number Reference number within the agency FI technical display location C10M 105: 04) C10N 20:00 20:02 30:00 40:24 (72) Inventor Yoshihisa Saeki Wako Saitama Ichichuo 1-4-1 Stock Company Honda Technical Research Institute

Claims (2)

[Claims] 1. A first component having a content C ₁ of 20% by weight ≦ C ₁ ≦ 60% by weight, and a content C ₂ of 2% by weight ≦ C ₂ ≦ 10.
It is composed of the second component, which is wt%, and the remaining third component, and has a kinematic viscosity V _{1 at} 40 ° C. of V ₁ ≦ 15 cSt.
Wherein the first component has a carbon number N ₁ of 1
6 ≦ N ₁ ≦ 18 at least one of unsaturated fatty acid methyl ester and unsaturated fatty acid ethyl ester, and the second component is an oil-soluble polyacrylic acid alkyl ester having an alkyl group having a carbon number N ₂ of N ₂ ≦ 18, and It is at least one kind of oil-soluble polymethacrylic acid alkyl ester, the third component is compatible with the first and second components, and has a boiling point Bp of 250 ° C. ≦ Bp ≦ 310 ° C.
A lubricating oil for plastic working of metal materials, which is a hydrocarbon oil. 2. The lubricating oil for plastic working of a metal material according to claim 1, wherein the hydrocarbon oil comprises at least one of mineral oil, isoparaffin, olefin and n-α olefin.