CN1058757C

CN1058757C - Method for nickel-base high-temp. alloy forging and bar acquiring uniform superfine crystalline grain

Info

Publication number: CN1058757C
Application number: CN96115293A
Authority: CN
Inventors: 陈宗霖; 王少刚; 姜兆群; 刘秋生; 陈桂梅; 李伟红; 刘润广; 韩雪
Original assignee: LIMING ENGINE MANUFACTURE CO SHENYANG
Current assignee: LIMING ENGINE MANUFACTURE CO SHENYANG
Priority date: 1996-05-09
Filing date: 1996-05-09
Publication date: 2000-11-22
Anticipated expiration: 2016-05-09
Also published as: CN1165204A

Abstract

The present invention relates to an even ultrafine grain obtaining method for GH4169 forged pieces and bars. The even ultrafine grain obtaining method is characterized in that an even reticular Widmanstatten delta-phase structure is obtained by pretreatment, and then a fresh fine-crystal nucleus surrounded by spherical delta-phases is obtained by deformation, the final state can be DA or have high quality and high strength, and the pretreatment, the deformation and the final molding can be carried out on common forging equipment. When the present invention is used for one item of grain refining, the physicochemical detection expense can be reduced by 24%; the present invention is suitable for directly producing fine-crystal bars of various specifications in aeronautical and astronautical engine plants, professional forge plants and steel plants.

Description

The method of a kind of nickel base superalloy forging and bar acquiring uniform superfine crystalline grain

The present invention relates to a kind of each forging of nickel base superalloy GH4169 alloy, as dish, impeller, ring, axle and blade; All kinds of bars, as forge rod, roll rod, the method for the above uniform superfine crystalline grain of ASTM10 level obtained.

As everyone knows, the GH4169 alloy is widely used in the key components and parts manufacturing in Aeronautics and Astronautics, Nuclear power plants and the petrochemical industry, such as the turbine disk on the gas-turbine engine, compressor disc, annular element, turboshaft and compressor blade or the like.And, then require the even refinement of grain fineness number of this alloy to reach more than the ASTM10 level in order to improve high and low all fatigue propertys of the above-mentioned strength member of internal combustion turbine.U.S. Pat 3660177 has proposed a kind of 1N718 alloy forged piece that adopts hot mechanical workout to produce to have even small grains and the method for bar.But, the ins and outs deficiency that this method discloses, especially forging temperature is lower, and the metallographic structure of separating out is short and thick needle-like Wei Shi body δ phase, thereby finish-forging is required relatively harsher.Adopt general thin brilliant technology, this alloy is at the uniform superfine crystalline grain that is difficult on the general forging equipment reach more than the ASTM10 level.

The object of the present invention is to provide a kind of at common forging equipment, on hammer, pressing machine, hydropress and common rolling mill, looping mill, just can make GH4169 superalloy forging or bar obtain the method for the easy handling of the above uniform superfine crystalline grain of ASTM10 level.

Technical solution of the present invention is after the blanking blank to be separated out the δ phase, by to the hot mechanical workout of blank, finally shaping and thermal treatment, makes alloy obtain uniform superfine crystalline grain.Be characterized in separating out the blue shape Wei Shi of uniform net body δ phase by following step: a. is at 1010 ℃--1030 ℃ of distortion of carrying out greater than 25% of giving, b. carry out blue processing of the net first time, processing parameter 880--900 ℃ of insulation 8--10h air cooling, c. jacket and forging or rolling after carry out that second time net is blue to be handled, processing parameter is handled with net is blue for the first time.In addition, net for the first time blue handle and jacket after, blank is out of shape greater than 30% forging or rolling at 1010 ℃-1030 ℃.Secondly, net is blue for the second time handle after, blank is out of shape finish-forging or the finish to gauge greater than 25% on common forging equipment, processing parameter is got 980 ℃-1010 ℃ and look the blank size and specific requirement employing air cooling, oil cooling or water-cooled.At last, 720 ℃ of-620 ℃ of direct aging or 970 ℃ of 1h solid solutions, then 720 ℃ of-620 ℃ of ageing treatment.Like this, can obtain the forging and the bar of the above uniform superfine crystalline grain of the high-strength state of DA state (the former) or high-quality (latter) ASTM10 level.Certainly when the blank grain size is relatively more even, in the step of separating out the δ phase, can not carry out predeformation, promptly directly carry out blue processing of the net first time after the blanking.When the grain size of the blue processing of net first time back blank compares uniform tissue, in the step of separating out the δ phase, can not carry out directly carrying out finish-forging or finish to gauge after the blue processing of the net second time is jacket.In addition, when ausforming equipment was adopted in final shaping, blank carried out needn't can carrying out finish-forging or finish to gauge by jacket after blue processing of the net first time.

See embodiment below in conjunction with accompanying drawing.

Accompanying drawing 1 is a process flow sheet of the present invention.Wherein, by the blanking operation to forging or rollingly being called pre-treatment for the first time, to finish-forging or finish to gauge, be called pre-treatment for the second time, the two adds can unite together and is referred to as pre-treatment, its objective is and obtain the blue shape Wei Shi of more equally distributed net body δ phase constitution structure earlier, be out of shape being lower than under the δ phased soln temperature then, it is broken mutually to net blue shape Wei Shi body δ, obtain spherical δ phase constitution, surround new net orchid mutually by spherical δ, form new close grain circumference, make in heat treatment process subsequently that thin crystalline substance is further perfect, crystal grain is further even.Accompanying drawing 2 is the metallographic structure figure after a kind of embodiment blanking.Its chemical ingredients sees Table one, and wherein, alloy is non-timeliness state, and chemical ingredients is not strict with, and does not have obvious niobium segregation, and grain fineness number is the ASTM5-7 level, is that typical crystal grain skewness example is a chain.Institute's material down press the processing of figure one flow process, and net is blue for the first time obtains the blue shape Wei Shi of more equally distributed net body δ phase (seeing accompanying drawing 3) after handling, and forging or rolling behind the sticking and 1Cr18Ni9Ti plate jacket obtains spherical δ phase constitution (seeing accompanying drawing 4) with aluminum silicate fiber.At last, mould is through just direct finish-forging on ordinary press of preheating.In heat treatment step, DA has obtained uniform superfine crystalline grain tissue (seeing accompanying drawing 5) and δ phase constitution structure (seeing accompanying drawing 6) after handling; After handling, solid solution aging obtained uniform superfine crystalline grain tissue (seeing accompanying drawing 7) and δ phase constitution structure (seeing accompanying drawing 8).Accompanying drawing 9 is the situation of another kind of embodiment, i.e. the metallograph that grain structure is evenly distributed after the blanking.Its Chemical Composition sees Table 2, alloy state wherein, and grain size numbers etc. are all identical with last example.At this moment, not carrying out predeformation handles and directly enters the blue treatment process of net and can obtain the blue shape Wei Shi of equally distributed as shown in Figure 3 net body δ phase.Press Fig. 1 flow process and continue processing, finally still can obtain uniform superfine crystalline grain as accompanying drawing 5 and accompanying drawing 7.

The invention has the advantages that it is that pre-treatment or final shaping all were not limited to conventional extruding and known extrusion ratio 4: 1, but can select to forge according to the product processing requirement, forming technology such as rolling or extruding.Simultaneously, select easy handling, cheap sheathing process, proposed a pre-treatment and twice pretreatment technology more flexibly, can on common hammer, pressing machine, hydropress, milling train and looping mill, be shaped.At last, can obtain under direct aging and the solid solution aging two states equally distributed ultrafine-grained (UFG) microstructure more than the ASTM10 level through thermal treatment.It should be the blue shape Wei Shi of equally distributed net body δ phase that the present invention has disclosed the middle blank tissue that obtains superfine crystal particle.In addition, without pretreated blank, though utilize the isothermal extruding also to can not get uniform superfine crystalline grain, and after pre-treatment, utilize common forging and pressing all can obtain the illustration of uniform superfine crystalline grain in the foregoing description, show that pre-treatment of the present invention is the prerequisite that GH4169 forging, bar obtain superfine grained structure.In a word,,, adopt the present invention, alloy property is stablized, improved quality product significantly, improved the tired and anti-ability that ruptures of high and low week than common thin brilliant technology because alloy recrystallization is abundant owing to separate out the blue shape Wei Shi body δ phase of net.And because homogeneous microstructure can significantly reduce the production testing project, only this item can increase economic efficiency 24%.The present invention promptly can be used for common forging, can be used for again that isothermal is super moulds forging, workable, be not only applicable to each Aeronautics and Astronautics engine works, professional forge works, and can extend to steel mill, direct production all size high-quality thin brilliant GH4169 forging and bar.The present invention is simple and easy, reasonable, practical, is suitable for China's enterprise present situation, has very considerable economic and promotional value.

Table 1

C	S	P	Si	Fe	Cr	Ni	Mo	Ti	Al	B	Nb
C	S	P	Si	Fe	Cr	Ni	Mo	Ti	Al	B	Nb	0.02	＜0.015	＜0.015	＜0.35	Surplus	17.00	50.00	2.80	0.75	0.70	＜0.006	5.00

Table 2

C	S	P	Si	Fe	Cr	Ni	Mo	Ti	Al	B	Nb
C	S	P	Si	Fe	Cr	Ni	Mo	Ti	Al	B	Nb	0.04	＜0.002	＜0.015	＜0.14	Surplus	18.77	52.31	2.92	1.01	0.61	＜0.006	5.09

Claims

1, a kind of nickel base superalloy GH4169 forging and bar obtain the method for the above uniform superfine crystalline grain of ASTM10 level, and wherein alloying constituent does not have more than obvious niobium segregation, the grain fineness number ASTM4 level and is non-timeliness state, it by

---after the blanking blank separated out the δ phase

---blank is carried out hot mechanical workout

---the final shaping

---thermal treatment is formed, and it is characterized in that:

---separate out the blue shape Wei Shi of uniform net body δ phase by following step:

A. at 1010 ℃--1030 ℃ of distortion of carrying out greater than 25% of giving:

B. carry out the blue processing of the net first time, 880 ℃ of processing parameters--900 ℃, insulation 8～10h air cooling;

C. jacket and forging or rolling after carry out that second time net is blue to be handled, processing parameter is handled with net is blue for the first time;

---for the first time net blue handle and jacket after, blank is out of shape greater than 30% forging or rolling at 1010 ℃～1030 ℃;

---for the second time net is blue handle after, blank is out of shape finish-forging or the finish to gauge greater than 25% on common forging equipment, processing parameter is got 980 ℃～1010 ℃ and look the blank size and air cooling, oil cooling or water-cooled are adopted in specific requirement;

---thermal treatment can be adopted 720 ℃ then of 720 ℃～620 ℃ direct aging or 970 ℃ of 1h solid solutions--620 ℃ of ageing treatment:

2, nickel base superalloy GH4169 forging according to claim 1, bar obtain the method for the above uniform superfine crystalline grain of ASTM10 level, it is characterized in that: when the grain size of blank relatively evenly the time, in the step of separating out the δ phase, can not give distortion, promptly directly carry out blue processing of the net first time after the blanking.

3, nickel base superalloy GH4169 forging according to claim 1 and 2, bar obtain the method for the above uniform superfine crystalline grain of ASTM10 level, it is characterized in that: when the grain size of blank is relatively more even after netting blue processing the first time, in the step of separating out the δ phase, can carry out netting the second time and directly carry out finish-forging or finish to gauge after blue processing is jacket.

4, nickel base superalloy GH4169 forging according to claim 1 and 2, bar obtain the method for the above uniform superfine crystalline grain of ASTM10 level, it is characterized in that: when ausforming equipment was adopted in final shaping, blank carried out needn't can carrying out finish-forging or finish to gauge by jacket after blue processing of the net first time.

5, nickel base superalloy GH4169 forging according to claim 3, bar obtain the method for the above uniform superfine crystalline grain of ASTM10 level, it is characterized in that: when ausforming equipment is adopted in final shaping, blank carries out first time and needn't can carry out finish-forging or finish to gauge by jacket after the processing of net orchid.