The aerial near isothermal forging method of GH4169 alloy plate shaped forgeable piece
Technical field
The present invention relates to a kind of forging method of wrought superalloy forging, particularly the aerial near isothermal forging method of GH4169 alloy plate shaped forgeable piece.
Background technology
The GH4169 alloy is a kind of nickel-chromium-iron-base superalloy of precipitation strength type, this alloy has higher intensity, the disk forge piece of this alloy such as the turbine disk are at the core hot-end component that is widely used in aerospace engines such as Aeronautics and Astronautics below 650 ℃, can long-term work under high temperature, heavily stressed, high rotating speed, high velocity air environment, it is abominable to adapt to Service Environment, live load is big, the extreme working environment requirement that failure-frequency is higher.This alloy is because the intensity height, and the deformation temperature narrow range causes its resistance of deformation bigger, makes comparatively difficulty of forging and molding, and will seek out the tiny high strength disk forge piece of crystal grain and at first must make the crystal grain of forging blank tiny.
On June 2nd, 2004 disclosed Chinese invention patent specification CN1500577A (application number: 200310103692.4) disclose a kind of accurate isothermal forging of nickel-base heat resisting superalloy, described accurate isothermal forging is meant the forging that the temperature difference of the heating-up temperature of the heating-up temperature of forging die and forge piece blank reheating is carried out between 56 ℃~250 ℃.This patent application has been explained rough forging and can have been adopted the blank of consolidated powder blank or casting-forging to provide, preferred consolidated powder blank.This patent application forges how to obtain the tiny blank of crystal grain or forging is fully not open to the blank that adopts casting-forging, and the original blank of casting or forging is to be difficult to obtain the tiny forging of crystal grain after the forging method that adopts this patent application to provide forges original blank because crystal grain is thicker.Adopt the consolidated powder blank to carry out accurate isothermal forging, the one, the consolidated powder blank needs special metal powder-making technique and powder manufacturing apparatus could produce, and at present since the difficulty of metal powder-making technique than greatly and the investment of powder manufacturing apparatus higherly makes the cost of consolidated powder blank higher, price is more expensive; The 2nd, the metal powder-making technique causes and adopts the forging quality of consolidated powder blank production to play pendulum because the technical barrier that need capture is more; The 3rd, the emerging technology in the metal powder-making technique side of belonging to, popularization and application does not cause the acquisition of consolidated powder blank difficult as yet.In addition, the described forging method of this patent application only heats forging die in the process of forging and molding, causes that rough forging is exposed to the temperature that is unfavorable for keeping rough forging in the air in the forging process; And the temperature difference of the accurate isothermal forging of forging die temperature and blank is 56 ℃~250 ℃, because temperature range is bigger, is unfavorable for accurately controlling the thermal parameter of forging, obtains the forging of tissue and function admirable; This patented method realizes that to the great pressure of needs the accurate isothermal forging of nickel-base heat resisting superalloy is also not mentioned.
In view of this, the invention provides the aerial near isothermal forging method of a kind of GH4169 alloy plate shaped forgeable piece.
Summary of the invention
The technical problem to be solved in the present invention provides the thin brilliant blank of a kind of use and accurate near isothermal forging temperature realizes the aerial near isothermal forging method of GH4169 alloy plate shaped forgeable piece, adopts this method can forge this tiny alloy plate shaped forgeable piece of crystal grain and makes forging have high strength.
For solving the problems of the technologies described above, the aerial near isothermal forging method of GH4169 alloy plate shaped forgeable piece of the present invention is realized by the following technical solutions:
At first provide the forging press of forge furnace, elongator, band forging die and rotary heating furnace and the original bar of GH4169 alloy of casting or forging, then operation according to the following steps:
The first step: in air, the original bar of GH4169 alloy is heated to 995 ℃~1005 ℃ initial temperature after, after jumping-up+pulling+heating and upsetting+punching again+heat roll off again, obtain the thin brilliant blank of annular;
Second step: in air, heat the initial temperature of described thin brilliant blank to 995 ℃~1005 ℃, add the initial temperature of upper and lower forging die to 950 ℃ on the hot press forge~965 ℃ simultaneously;
The 3rd step: the thin brilliant blank after heating is packed into and be positioned between the upper and lower forging die of forging press, in air, utilize the rotary heating furnace of forging press that described thin brilliant blank and upper and lower forging die are heated;
The 4th the step: in the initial temperature scope of described thin brilliant blank and upper and lower forging die, described upper and lower forging die by forging press provide forging pressure in air described thin brilliant blank excellent suitability for press forming, obtain disk forge piece.
For making the present invention reach best implementation result, preferred 1005 ℃ of the heating-up temperature of the original bar of above-mentioned GH4169 alloy, preferred 1005 ℃ of the heating-up temperature of thin brilliant blank, preferred 950 ℃ of the heating-up temperature of upper and lower forging die; And ceaselessly thin brilliant blank and upper and lower forging die are heated to keep its temperature in described initial temperature scope at rotary heating furnace described in the whole forging process always; The mold materials of upper and lower forging die adopts cast superalloy, and preferred K403 alloy can satisfy disk forge piece preferably and be shaped.
To offer the forging pressure of upper and lower forging die be 55MN~65MN to forging press when adopting forging method of the present invention to forge, and can make the strain rate of thin brilliant blank when excellent suitability for press forming reach 0.01s
-1~0.05s
-1, preferred 0.03s
-1, described strain rate is determined by the movement velocity of forging press top shoe.
The disk forge piece that adopts forging method of the present invention to forge adopts water-cooled to handle after forging.
Compared with prior art, beneficial effect of the present invention is as follows:
The aerial near isothermal forging method of GH4169 alloy plate shaped forgeable piece of the present invention, because adding by upsetting pull, a casting or the original blank that forges such as GH4169 alloy bar material be shaped by near isothermal forging again after roll off technology is made into thin brilliant blank, the grain size of GH4169 alloy 4 grades of original blank before forge are refine to carry out near isothermal forging again behind 8 grades of thin brilliant blank and can bring up to 11 grades (described grain size is Unite States Standard ASTM level) to the grain size of forging the back disk forge piece, greatly refinement the crystal grain of this alloy material, thereby can obtain high-intensity disk forge piece.
The present invention uses the GH4169 alloy original blank of casting or forging to obtain the tiny and higher disk forge piece of intensity of crystal grain, can not rely on the intensity that adopts the consolidated powder blank to come crystal grain thinning and improve forging, thereby greatly reduced the forging cost, and original blank is easy to obtain, and helps applying of near isothermal forging method.
Near isothermal forging method of the present invention ceaselessly heats forging die and blank owing to rotary heating furnace in forging process always, can keep forging die and blank in the temperature range of regulation, to forge, and can be controlled at 30 ℃~55 ℃ to the temperature difference of the near isothermal forging of forging die temperature and blank temperature, because temperature range is less, help accurately controlling the thermal parameter of forging such as equivalent strain, temperature, strain rate etc., obtain the forging of tissue and function admirable; And the present invention also provided concrete parameter to the requirement of adopting great forging pressure to satisfy strain rate in the forging process, makes the operability of this forging method stronger.
Embodiments of the invention and accompanying drawing have provided the near isothermal forging manufacturing process of the GH4169 alloy plate shaped forgeable piece that a kind of shape is comparatively complicated, deflection is bigger in addition, adopt the shape and size of the disk forge piece that this method forges to distribute along the part profile substantially, not only realized the Plastic Forming of difficult distortion GH4169 alloy material disk forge piece, but also can realize the near-net-shape of disk forge piece, forge disk forge piece near part shape and size; Owing to the fire that is heated to be of blank, reduced the surface oxidation decortication phenomenon of blank during forging, helped improving the dimensional accuracy of disk forge piece, saved a large amount of valuable GH4169 alloy material and machine and add expense.
Description of drawings
The present invention is further detailed explanation below in conjunction with the drawings and specific embodiments.
Fig. 1 is the process chart of the aerial near isothermal forging method of GH4169 alloy plate shaped forgeable piece.
Fig. 2 is the installation diagram of the forging press, forging die and the rotary heating furnace that are used to implement near isothermal forging method of the present invention.
Fig. 3 is the state diagram that thin brilliant blank is put into forging die.
Fig. 4 is that forging die is the state diagram of thin brilliant blank excellent suitability for press forming.
Fig. 5 is the sectional view of disk forge piece.
Fig. 6 is the interior tissue metallograph of thin brilliant blank.
Fig. 7 is the interior tissue metallograph of disk forge piece.
The specific embodiment
Implement the aerial near isothermal forging method of GH4169 alloy plate shaped forgeable piece of the present invention, the forging press of forge furnace, elongator, band forging die and rotary heating furnace and the original bar of GH4169 alloy of casting or forging need be provided.
Fig. 1 shows the GH4169 alloy plate shaped forgeable piece carries out near isothermal forging in air technological process.
Fig. 2 shows the forging press 9 that is used to implement near isothermal forging method of the present invention, the assembling situation that goes up forging die 6, anvil tool 4 and rotary heating furnace 3, following anvil 2 fixedly is housed on the workbench 1 of forging press 9 successively with anvil tool 4, workbench 1 is connected with slide block 8 by guide pillar 10, slide block 8 can slide up and down on guide pillar 10, anvil 7 and last forging die 6 on slide block fixedly is equipped with for 8 times successively; Between last anvil 7 and following anvil 2, rotary heating furnace 3 is housed, rotary heating furnace 3 is divided into two joints along short transverse, going up of this stove saves the bottom surface that is fixed on anvil 7, following joint be fixed on down anvil 2 above, dismountable heat insulation loop 11 is housed between the upper and lower joint of rotary heating furnace 3, and the die cavity when last forging die 6 and anvil tool 4 matched moulds is the die cavity of disk forge piece 12 of the present invention.Among the figure also with the double dot dash line original state of thin brilliant blank 5 when putting into forging dies of schematically having drawn.
Fig. 3 shows the position relation that is in when thin brilliant blank 5 is put into forging die between forging die 6 and the anvil tool 4
Fig. 4 illustrates the end-state that forging die 6 and anvil tool 4 forge into thin brilliant blank 5 disk forge piece 12.
Fig. 5 shows the structure that adopts the disk forge piece 12 that near isothermal forging method of the present invention forges.
Fig. 6 shows the interior tissue structure of thin brilliant blank 5, and the multiplication factor of microscopically is 100 times.
Fig. 7 shows the interior tissue structure of disk forge piece 12, and the multiplication factor of microscopically is 100 times.
The operating procedure of implementing the aerial near isothermal forging method of GH4169 alloy plate shaped forgeable piece of the present invention is as follows:
The making of the thin brilliant blank 5 of step 1:GH4169 alloy.GH4169 alloy bar material by the blanking of disk forge piece specification is heated to 995 ℃~1005 ℃ initial temperature in forge furnace, preferred temperature is 1005 ℃, and jumping-up pulls out former height again to certain altitude on forging press then; Punching behind the heating and upsetting again; After the blank heating with holes on elongator roll off become the ring base of disk forge piece to obtain the thin brilliant blank 5 of GH4169 alloy.The grain size of thin brilliant blank 5 can reach 8 grades of U.S. ASTM standards, and its interior tissue structure as shown in Figure 6.
Step 2: heat thin brilliant blank 5 and last forging die 6, anvil tool 4.Thin brilliant blank 5 is put into the initial temperature that forge furnace is heated to 995 ℃~1005 ℃, and preferred temperature is 1005 ℃; Open under the matched moulds state of forging die 6 and anvil tool 4 on shown in Figure 2 simultaneously rotary heating furnace 3 on forging die 6 and anvil tool 4 be heated to 950 ℃~965 ℃ initial temperature, preferred temperature is 950 ℃.Described go up forging die 6 and anvil tool 4 in forging process the forging die initial temperature and strain rate under the yield strength that had need greater than more than 3 times of thin brilliant blank 5 flow stresses, thereby select for use cast superalloy to do the forging die material, preferred K403 cast superalloy material.
Step 3: thin brilliant blank 5 dress mould location.Unload heat insulation loop 11, open forging press 9, slide block 8 along guide pillar 10 upwards slide and by last anvil 7 with the following joint certain height that joint breaks away from anvil tool 4 and rotary heating furnace 3 that goes up that goes up forging die 6 and rotary heating furnace 3, close forging press 9.As shown in Figure 3, thin brilliant blank 5 is positioned to load onto heat insulation loop 11 between forging die 6, the anvil tool 4, finishes the dress mould location of thin brilliant blank 5.Rotary heating furnace 3 does not stop heating in this step.
Step 4: heat thin brilliant blank 5 and last forging die 6, anvil tool 4.Utilize 3 pairs of thin brilliant blanks 5 of rotary heating furnace and last forging die 6, anvil tool 4 to heat, cause the thermal loss of thin brilliant blank 5 with minimizing because of the temperature difference between last forging die 6, anvil tool 4 and the thin brilliant blank 5, thereby thin brilliant blank 5 is remained in forging process in the temperature range of regulation.In heating process because thereby heat insulation loop 11 has been blocked the upper and lower joint of rotary heating furnace 3 opens the stove seam that causes and can avoid the heat in the stove to scatter and disappear.
Step 5: thin brilliant blank 5 aerial near isothermal forgings are shaped.Open forging press 9, slide block 8 makes forging die 6 and anvil tool 4 obtain disk forge piece shown in Figure 5 12 to thin brilliant blank 5 excellent suitability for press forming by shown in Figure 4 along guide pillar 10 to lower slider, closes forging press 9.Described forging process carries out in air, and forging pressure is 55MN~65MN, and the forging strain rate of thin brilliant blank 5 in the forging and pressing process is 0.01s
-1~0.05s
-1, preferred 0.03s
-1, described strain rate is determined by the movement velocity of slide block 8.In this process, rotary heating furnace 3 heats last forging die 6, anvil tool 4 and thin brilliant blank 5 all the time.
Step 6: the water-cooled of disk forge piece 12 is handled.Take out disk forge piece 12 from forging press 9, carry out water-cooled and handle under the forging attitude, so far, whole near isothermal forging process finishes.The grain size of disk forge piece 12 can reach 11 grades of U.S. ASTM standards, and its interior tissue structure as shown in Figure 7.
Near isothermal forging of the present invention is meant the forging that the temperature difference of the heating-up temperature of the heating-up temperature of forging die and forge piece blank reheating is carried out between 30 ℃~55 ℃.