CN112845744A - Preparation method of metal solid-solid composite additive blank - Google Patents

Preparation method of metal solid-solid composite additive blank Download PDF

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CN112845744A
CN112845744A CN202110007429.3A CN202110007429A CN112845744A CN 112845744 A CN112845744 A CN 112845744A CN 202110007429 A CN202110007429 A CN 202110007429A CN 112845744 A CN112845744 A CN 112845744A
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blank
temperature
forging
deformation
heating
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CN112845744B (en
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张心金
王宝忠
刘凯泉
祝志超
杨康
朱琳
时立佳
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TIANJIN HEAVY EQUIPMENT ENGINEERING RESEARCH CO LTD
China First Heavy Industries Co Ltd
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TIANJIN HEAVY EQUIPMENT ENGINEERING RESEARCH CO LTD
China First Heavy Industries Co Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D11/00—Bending not restricted to forms of material mentioned in only one of groups B21D5/00, B21D7/00, B21D9/00; Bending not provided for in groups B21D5/00 - B21D9/00; Twisting
    • B21D11/10—Bending specially adapted to produce specific articles, e.g. leaf springs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J1/00—Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling
    • B21J1/04—Shaping in the rough solely by forging or pressing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J1/00—Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling
    • B21J1/06—Heating or cooling methods or arrangements specially adapted for performing forging or pressing operations
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
    • B21J5/002—Hybrid process, e.g. forging following casting
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
    • B21J5/008—Incremental forging
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21J—FORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J5/00—Methods for forging, hammering, or pressing; Special equipment or accessories therefor
    • B21J5/02—Die forging; Trimming by making use of special dies ; Punching during forging
    • B21J5/025—Closed die forging

Abstract

The invention relates to a preparation method of a metal solid-solid composite additive blank, which comprises the following steps: stacking and molding a plurality of initial blanks to obtain a prefabricated blank; welding the prefabricated blank to weld the bonding interfaces among the plurality of initial blanks to obtain a composite blank; heating the composite blank to a first temperature and preserving heat, performing first hot-press forging after the composite blank is heated to the first temperature to obtain a first forging blank, heating the first forging blank to a second temperature and preserving heat, heating the cover plate and the base plate to a third temperature and preserving heat, placing the first forging blank on the base plate after the first forging blank is heated to the temperature, sleeving a die on the first forging blank and the base plate, placing the cover plate on the first forging blank, performing second hot-press forging to obtain a second forging blank, removing the die, heating the second forging blank again to a fourth temperature and preserving heat, and obtaining an integrated composite blank after the second forging blank is heated to the temperature. Compared with the prior art, the method is more beneficial to interface compounding and oxide dispersion and fragmentation, enhances the homogenization degree and bonding strength of the interface and improves the material performance.

Description

Preparation method of metal solid-solid composite additive blank
Technical Field
The invention relates to the technical field of metal forging, in particular to a preparation method of a metal solid-solid composite additive blank.
Background
Forging is a process of using forging machinery to apply pressure to a metal blank to make it plastically deform to obtain a forging with certain mechanical properties, certain shape and size. The defects of as-cast porosity and the like generated in the smelting process of metal can be eliminated through forging, the microstructure is optimized, and meanwhile, because the complete metal streamline is preserved, the mechanical property of the forging is generally superior to that of a casting made of the same material. Important parts with high load and severe working conditions in related machines are mainly forged pieces except for plates, sections or welding pieces which are simple in shape and can be rolled.
The traditional forging method is difficult to produce large metal forgings, so that the existing method for preparing the large metal forgings adopts an additive blank manufacturing method, wherein the additive blank manufacturing method is to adopt a plurality of metal blanks with smaller volumes as initial blanks to be stacked and then subjected to vacuum sealing welding to prepare large-size metal composite blanks, and then the composite blanks are subjected to hot-pressing compounding to form integrated composite blanks so as to replace large cast ingots and achieve the purpose of manufacturing the large metal forgings by using metal blanks such as smaller casting blanks, forging blanks or rolling blanks and the like. The additive blank making technology can replace the traditional production mode of producing large metal forgings by large ingots, solves the quality problems of shrinkage porosity, shrinkage cavity, segregation and the like of the large metal forgings, has obvious superiority, and the produced large metal forgings can be comparable with electroslag products. Meanwhile, the additive blank manufacturing technology can also be used for additive manufacturing of composite blanks made of dissimilar materials, and the application range is wider.
However, the single-layer blank generally adopted by the existing additive blank manufacturing method is smaller than 300mm, and when a plurality of layers of blanks are compounded, the multi-layer joint surfaces of the upper and lower end blanks are in the difficult deformation area, so that the problem of uneven deformation of each joint surface due to the difficult deformation area and the tensile stress area during subsequent blank compounding is solved, and finally deformation and cracking are easy to occur during subsequent forging after compounding.
Disclosure of Invention
Aiming at the problems in the prior art, the invention provides a preparation method of a metal solid-solid composite additive blank, which comprises the following steps:
step S1, stacking and forming a plurality of initial blanks with clean surfaces to obtain a prefabricated blank;
step S2, welding the prefabricated blank to weld the bonding interfaces among the metal blanks to obtain a composite blank;
step S3, heating the composite blank to a first temperature T1And keeping the temperature, after reaching the temperature, at a deformation speed V1Deformation amount D1Carrying out first hot press forging to obtain a first forging stock, and then heating the first forging stock to a second temperature T2And preserving heat, and simultaneously heating the cover plate and the base plate to a third temperature T3And preserving heat, after the temperature is equalized, placing the first forging stock on the base plate, sleeving a mould on the first forging stock and the base plate, placing the cover plate on the first forging stock, and deforming at a speed V2Deformation amount D2Carrying out hot press forging for the second time to obtain a second forging stock, removing the die, and then heating the second forging stock to a fourth temperature T again4And keeping the temperature to the temperatureThen, obtaining an integrated composite blank; wherein, V2＞V1，D2＞D1。
Further, in step S3, the deformation speed V1Satisfies the following conditions: v is not more than 1mm/s1< 5mm/s, the deformation D1Satisfies the following conditions: 1% < D1Less than 5 percent; the deformation velocity V2Satisfies the following conditions: v is less than or equal to 10mm/s2Less than or equal to 60mm/s, the deformation D2Satisfies the following conditions: not less than 35 percent.
Further, the height of the first forging stock plus the height of the backing plate is less than the height of the die is less than the height of the first forging stock plus the height of the backing plate plus the height of the cover plate.
Further, in step S3, the mold has a cylindrical shape.
Further, the diameter of the cover plate is smaller than that of the die, the diameter of the backing plate is larger than that of the lower end face of the first forging stock, and the diameter of the cover plate is larger than that of the upper end face of the first forging stock.
Further, the first temperature T1Tm is more than or equal to 0.7, and the second temperature T2Tm is more than or equal to 0.7Tm, and the third temperature T is more than or equal to 0.5Tm3Tm is more than or equal to 0.25, and the fourth temperature T4≥0.7Tm。
Further, in the step S3, the first temperature T1The holding time of (1) is more than 1h, and the second temperature T2The holding time of (a) is more than 10h, and the third temperature T3The heat preservation time is more than 10h, and the fourth temperature T4The heat preservation time is more than 2 h.
Further, in the step S1, the mass of the initial billet is not less than 20 tons.
Further, in step S1, the shape of the initial blank is cylindrical.
Further, in step S2, the welding mode is vacuum electron beam welding, and the parameters of the vacuum electron beam welding are as follows: the degree of vacuum was 5.0X 10-3Pa-1.0×10-2Pa, acceleration voltage: greater than 50KV, beam current: greater than 200mA, focus current: greater than 500mA, power: greater than 10KW, welding rate: v is more than 50mm/s and less than 300 mm/s.
The invention has the beneficial effects that:
1. the invention can effectively solve the problem that when the initial blanks at the upper and lower ends are combined into a plurality of layers, the original blanks at the upper and lower ends have a plurality of layers of combined surfaces, the combined surfaces deform unevenly due to the existence of a difficult deformation area and a tensile stress area, and the deformation and the cracking during the subsequent forging are prevented.
2. The invention is beneficial to interface compounding and oxide dispersion and fragmentation, enhances the homogenization degree and bonding strength of the interface and improves the material performance.
3. The initial blank in the invention adopts a cylindrical blank, the cylindrical blank only has an upper surface, a lower surface and a cylinder surface, the efficiency of processing the cylinder surface is obviously higher than that of the peripheral surface of the continuous casting plate blank, and the blank does not need to be clamped for many times, so that the processing is convenient and the processing efficiency is high.
4. The primary purpose of the initial blank deformation of the present invention is to make the metal deformation more uniform, and in particular to make the deformation at the bonding interface of each layer more uniform and consistent, and to improve the hard deformation zone of the blank.
5. The initial blank is placed into the die to deform, so that the radiation heat release of the blank can be reduced, a certain heat preservation effect is achieved, and the high-temperature deformation capability of the blank is kept to a certain extent.
6. The initial blank is demoulded and then put into a furnace for three times of high-temperature heat preservation, so that the mechanical extrusion deformation defects generated on the interface after the secondary deformation are gradually and uniformly diffused and released, the element diffusion homogenization is promoted, and the preparation is made for the interface structure homogenization; and provides sufficient heat for subsequent hot working, and is easy to deform.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
FIG. 1 is a schematic representation of a first hot press forging in accordance with one embodiment of the present invention;
FIG. 2 is a schematic view of a second hot press forging operation according to an embodiment of the present invention;
FIG. 3 is a schematic representation of a second hot press forging in accordance with one embodiment of the present invention;
FIGS. 4 (a) and (b) are the microstructure diagrams of the bonding interface of the experimental group and the control group of example 1 of the present invention, respectively;
FIGS. 5 (a) and (b) are the fracture pattern of tensile fracture and the high-power microstructure of the core of tensile fracture at room temperature of the experimental group of example 1 according to the present invention, respectively;
FIGS. 6 (a) and (b) are the fracture pattern of the tensile fracture at high temperature and the high-power micro-morphology pattern of the tensile fracture core, respectively, of the experimental group in example 1 of the present invention;
FIGS. 7 (a) and (b) are the fracture pattern of tensile fracture and the high-power microstructure of tensile fracture core at room temperature of the control group in example 1 of the present invention, respectively;
FIGS. 8 (a) and (b) are the fracture pattern of the tensile fracture and the high-power microstructure of the tensile fracture core at high temperature of the control group in example 1 of the present invention, respectively;
FIG. 9 is a diagonal sectional dot view of an experimental group of example 2 of the present invention;
FIG. 10 is a diagonal sectional dot view of a control group in example 2 of the present invention.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the description of embodiments of the invention, the description of the term "some embodiments" means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. Throughout this specification, the schematic representations of the terms used above do not necessarily refer to the same implementation or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. The terms "first," "second," "third," and "fourth" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.
For a better understanding of the invention, and not as a limitation on the scope thereof, all numbers expressing speeds, amounts of deformation, temperatures, and other numerical values used in the present invention are to be understood as being modified in all instances by the term "about". Accordingly, unless expressly indicated otherwise, the numerical parameters set forth in the specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained. At the very least, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
Referring to fig. 1-3, wherein the letter p in fig. 1 and 3 represents pressure, the present invention provides a method for preparing a metal solid-solid composite additive blank, comprising:
and step S1, stacking and forming a plurality of initial blanks with clean surfaces to obtain the prefabricated blank.
Preferably, the initial blank is a cylindrical blank, the initial blank (namely, a metal blank) is mainly formed by freely upsetting and semi-closed upsetting cylindrical high-quality and large-tonnage casting blanks, the cylindrical blank is adopted, the cylindrical blank only has an upper surface, a lower surface and a cylinder surface, the surface efficiency of the processed cylinder surface is obviously higher than the peripheral surface of a continuous casting blank, and the blank does not need to be clamped for many times, so that the processing is convenient, the processing efficiency is high, the subsequent forging cost is greatly saved, and the quality risk is reduced. More preferably, the mass of the initial blank is more than or equal to 20 tons, and the large initial blank is adopted, so that the bonding interface of the composite blank does not fall into a difficult deformation area during subsequent hot-press forging due to the thickening of the initial blank, the bonding of the interface is effectively guaranteed, and the risk of interface cracking is reduced. It should be noted that, because the initial blank has a large weight, the pressure required by hot press forging is large, and a super-large press needs to be matched.
Specifically, in step S1, the method for preparing the initial blank with clean surface includes: and (3) carrying out surface polishing on the used initial blank, wherein the surface polishing can be carried out by adopting a milling machine, a lathe, a grinding machine, an abrasive belt, a grinding wheel, a steel wire and the like, and then cleaning the surface of the initial blank by adopting an organic solvent to obtain the initial blank with a clean surface. By grinding, on one hand, the single blank is subjected to integral sand blasting (or shot blasting) to effectively remove black oxide skin on all surfaces of the initial blank, so that the efficiency is high; meanwhile, as the binding effect of the cylinder on the interface is small, only the oxide skin on the surface of the cylinder needs to be effectively removed to be in a bright state, and the processing time can be effectively saved for the subsequent surface processing; on the other hand, the parallelism of the upper surface and the lower surface to be welded of the initial blank and the verticality of the edge of the blank are guaranteed, and the accuracy of the welding position when an electron beam welding gun moves during welding is effectively guaranteed. After polishing, the bonding surface of the initial blank is cleaned by adopting organic solvents such as absolute ethyl alcohol, acetone and the like, the cleaning degree value is represented by RFU (Relative Fluorescence Units) detected by a cleanliness meter, wherein RFU is less than or equal to 100, the initial blank is considered to be clean, so that the initial blank with a clean surface is obtained, the upper surface and the lower surface are polished and cleaned, then dried (30-50 ℃) or dried by hot air, and placed in a dry and clean environment to avoid the surface from generating rusting or secondary pollution and the like due to moisture, and the aim is to improve the quality and performance of the metal blank and reduce the fracture or crack generation during the subsequent metal blank upsetting.
And step S2, welding the prefabricated blank to weld the bonding interfaces among the plurality of initial blanks to obtain the composite blank.
Specifically, in step S2, the welding mode is one of vacuum electron beam welding, induction heating and friction stir welding, sealing welding is performed under vacuum conditions (vacuum degree is less than or equal to 0.1Pa), weld penetration is greater than or equal to 15mm, and no leakage point exists at the welding part after detection, so as to obtain the composite blank. For vacuum electron beam welding, in order to guarantee the quality of a welding seam, the following parameters are required: acceleration voltage: > 50KV, beam current: > 200mA, focusing current: > 500mA, power: > 10KW, welding rate: v is more than 50mm/s and less than 300 mm/s. Through the parameters, the method can effectively ensure that the welding seam has no meat deficiency and no welding leakage after the vacuum electron beam welding, and effectively ensure the weld penetration and the uniformity of the welding seam.
Step S3, heating the composite blank to a first temperature T1And keeping the temperature, after reaching the temperature, at a deformation speed V1Deformation amount D1Carrying out hot press forging for the first time to obtain a first forging stock, and then heating the first forging stock to a second temperature T2And preserving heat, and simultaneously heating the cover plate and the base plate to a third temperature T3And keeping the temperature, after the temperature is equalized, placing the first forging stock on a base plate, sleeving a mould on the first forging stock and the base plate, placing a cover plate on the first forging stock, and deforming at a speed V2Deformation amount D2Carrying out hot press forging for the second time to obtain a second forging stock, removing the die, and heating the second forging stock to the fourth temperature T again4And preserving the heat until the temperature is reached to obtain an integrated composite blank; wherein, V2＞V1，D2＞D1。
Specifically, firstly, a hydraulic press is adopted for forging and pressing compounding, the composite blank is placed in a resistance furnace and is heated by adopting a two-stage heating process, and the two-stage heating process comprises the following steps: increasing from room temperature to an austenite transformation temperature (AC3 temperature) at a first ramp rate, and increasing from an AC3 temperature to the first temperature at a second ramp rate, wherein the first ramp rate > the second ramp rate. Secondly, the first hot-press forging is carried out by adopting low-speed and small deformation, because the initial blank is large, the whole initial blank is not completely hot after passing through a resistance furnace, the external temperature of the initial blank firstly reaches the preset heat preservation temperature according to the heat transfer rule when the initial blank is heated, and the core part does not reach the preset heat preservation temperature. Heating and insulating the first forging stock, heating and insulating the cover plate and the base plate, placing the first forging stock on the base plate after the temperature is equalized, sleeving the die on the first forging stock and the base plate, and placing the cover plate on the first forging stock; by adopting the heated cover plate and the heated base plate, the first forging stock enters the die to deform, so that the radiation heat release of the stock can be reduced, a good heat preservation effect is achieved, the temperature drop of the stock is obviously reduced, and the deformation resistance is reduced; simultaneously, a certain amount of pre-deformation is given, the second hot-press forging is carried out, and the first forging stock is deformed in place in one step through rapid deformation in the die; the oxide film can be quickly broken, the temperature drop of the blank is reduced, meanwhile, the blank is quickly deformed, the internal heat of the blank is quickly gathered in a short time, and the internal temperature of the blank is quickly raised under the comprehensive actions of conversion of mechanical energy, heat preservation of a die, a cover plate and a base plate and the like, so that the dispersion and meltback of the oxide are greatly promoted, and the mechanical mixing of interface metals and the uniform mixing of elements are promoted; and (3) demoulding the second forging stock after the secondary deformation, and then placing the second forging stock into a resistance furnace for carrying out high-temperature heat preservation for three times, so that the mechanical extrusion deformation defects generated on the interface after the secondary deformation are gradually and uniformly diffused and released, the element diffusion homogenization is promoted, the preparation is made for the interface structure homogenization, sufficient heat is provided for the subsequent hot working, and the second forging stock is easy to deform.
More specifically, the primary purpose of the initial billet deformation is to make the metal deformation more uniform, especially to make the deformation of the bonding interface of each layer more uniform and consistent, improve the hard deformation zone of the billet, the first forged billet after the primary deformation of the first hot press forging is put into a resistance furnace again for heating and heat preservation, and simultaneously a layer of high silica cloth (the thickness is more than 1mm, at room temperature, the material is soft cloth, can be sintered into brittle solid with certain hardness at high temperature, has certain high temperature oxidation prevention function, can be uniformly extended along with the surface of the first forged billet under the action of pressure, has lubricating function, and then can be uniformly extended along with the first forged billet at the set second temperature T2Heating and preserving heat at the lower part, and discharging the heated and preserved heat out of the resistance furnace; the cover plate and the base plate are put into another resistance furnaceMedium heating to a third temperature T3Laying a layer of high silica cloth (the thickness is more than 1mm) on the surface of the base plate, wherein the heating temperature of a heating resistance furnace is lower than the heating temperature of the first forging stock, for example, the heating temperature of a blank is 1250 ℃, and the heating temperature of the cover plate and the base plate is set to be 800 ℃ so that the base plate steel plate can be repeatedly used and has certain rigidity; die steel H13 can be selected for the backing plate material, and the material of concrete backing plate can be selected according to actual conditions by oneself.
In the prior art, the blank prepared by the continuous casting plate blank has a plurality of bonding interfaces, and a plurality of interfaces are positioned in a difficult deformation area, so that the problem of cracking of the blank interface is easy to occur when the blank is subjected to forging and pressing compounding and then is drawn in a rotating direction.
Preferably, the first temperature rise rate is 200-; the second temperature rise rate is 100-.
Preferably, in step S3, the deformation speed V is 1mm/S ≦ 1mm/S1Less than 5mm/s, 1% < deformation D1Less than 5 percent; since the initial billet is not completely heat-penetrated at the first forging, the deformation amount is not likely to be excessively large. Deformation speed V is less than or equal to 10mm/s2Less than or equal to 60mm/s, and deformation D2Not less than 35 percent, quickly breaking the oxide film and reducing the temperature drop of the initial blank.
Preferably, the height of the first forging stock + the height of the base plate < the height of the die + the height of the base plate + the height of the cover plate, the height of the cover plate is convenient for the cover plate to be placed on the upper end face of the first forging stock and the die to be placed in the base plate and the first forging stock, and the height of the specific die, the height of the base plate and the height of the cover plate can be automatically set according to the height of the first forging stock.
Preferably, in step S3, the mold is cylindrical, although the shape of the inner wall of the cylindrical mold can be adjusted by itself.
Preferably, the diameter of the cover plate is less than that of the die, the diameter of the backing plate is greater than that of the lower end face of the first forging stock, the diameter of the cover plate is greater than that of the upper end face of the first forging stock, the inside of the die is prone to exhaust outwards when the die is pressed and deformed, and the diameter of the specific die, the diameter of the cover plate and the diameter of the backing plate are set according to the specific diameter of the first forging stock.
Preferably, the first temperature T1Tm is more than or equal to 0.7, and the second temperature T2Tm is more than or equal to 0.7Tm, and the third temperature T is more than or equal to 0.5Tm3Tm is more than or equal to 0.25, and the fourth temperature T4Tm is more than or equal to 0.7, and Tm is melting point temperature and the unit is ℃. Heating the initial blank to a first temperature T before forging1Under the condition, the initial blank is soft, has good forgeability, is easy to deform and process, and is not easy to crack during forging. Second temperature T2And the Tm is more than or equal to 0.7Tm, and after the first hot-press forging, the heating and heat preservation between forgings are implemented to ensure that the whole first forging is completely hot so as to smoothly carry out the large plastic deformation treatment of the second stage. Third temperature T3Under the condition of (2), after the temperature is too high, the strength is reduced, and the repeated use is not facilitated. Fourth temperature T4Under the conditions (2), the uniformity of element diffusion is promoted.
Preferably, in step S3, the first temperature T1The holding time is more than 1h, and the second temperature T2The heat preservation time is more than 10h, and the third temperature T3The heat preservation time is more than 10h, and the fourth temperature T4The heat preservation time is more than 2 h. The specific holding time is determined according to the initial blank size. When the initial blank size is smaller, the holding time can be reduced properly, for example, 10-60min, and when the initial blank size is larger, the holding time should be prolonged properly to ensure that the temperature of the initial blank is suitable for hot press forging.
Compared with the prior art, the method can effectively solve the problem that when the initial blanks at the upper and lower ends have multi-layer combined surfaces during compounding of the multi-layer initial blanks, the combined surfaces deform unevenly due to the existence of a difficult deformation area and a tensile stress area, and prevent deformation cracking during subsequent forging; the invention is beneficial to interface compounding and oxide dispersion and fragmentation, enhances the homogenization degree and bonding strength of the interface and improves the material performance.
Example 1
Experimental groups:
step S1, adopting an initial blank with a material of 508gr.3, wherein the size of the single initial blank is:
Figure BDA0002884076130000091
the single initial blank is formed from
Figure BDA0002884076130000092
The method comprises the following steps of heating an original blank at a high temperature (the heating temperature is 1230 ℃), performing closed upsetting, cooling the blank to room temperature, performing integral sand blasting to remove oxide skins on all surfaces, brightening the surface of a cylinder, respectively removing rust layers and oxide layers on the upper and lower combined surfaces of the original blank and a cylinder welding zone by a milling machine and a lathe, ensuring the parallelism of the upper and lower surfaces to be welded of the original blank, the verticality of the cylinder of the original blank and the roughness of the upper and lower surfaces to be 1.6 mu m, cleaning the surface of the original blank by absolute ethyl alcohol or acetone, removing oil stains on the surface, drying the blank by hot air (the temperature is controlled to be 30-50 ℃), obtaining an initial blank with a clean surface, vertically stacking 5 initial blanks with clean surfaces, and fixing the initial blanks by a fixture to obtain a prefabricated blank;
step S2, fixing the prefabricated blank on the vacuum electron beam welding worktable, moving into the vacuum chamber, vacuumizing, preparing formal welding when the vacuum degree of the vacuum chamber is less than or equal to 0.1Pa, and maintaining the welding vacuum degree at 5.0 x 10 during the formal welding-3-1.0×10-2Pa, welding acceleration voltage of 70kV, beam current of 220mA, focusing current of 580mA, welding seam depth of about 20mm, and obtaining a composite blank after assembly welding;
step S3, performing forging and pressing compounding by adopting a hydraulic press, putting the compound blank into a resistance furnace, heating to 1250 ℃ by adopting a two-stage heating process, and performing a first stage: rapidly raising the temperature from room temperature to 770 ℃ at 220 ℃/h, and in the second stage: slowly heating to 1250 ℃ from 770 ℃ at a speed of 150 ℃/h, preserving heat for 1h when reaching 1250 ℃ (because the blank size is small and the heat preservation can not be carried out according to the requirement of more than 1h of a large-size blank, the heat preservation time in a section of working procedure is shortened), transferring the heat-preserved composite blank to a press, pressing down at a deformation speed of 4mm/s and a deformation amount of 4%, pressing down for about 40mm, carrying out first hot-pressing forging to obtain a first forging blank, then covering a layer of high silica cloth on the first forging blank, returning to a resistance furnace together, heating to 1250 ℃ and preserving heat for 10h, transferring the first forging blank to the high silica cloth on a hot-state base plate of the press after the first forging blank is completely hot, preheating the base plate in advance, and measuring the surface temperature to be about 500 ℃. The cylinder mould is sleeved into the first forging stock, and then a pre-heated and preheated cover plate (the temperature of the cover plate is 500 ℃) is placed on the high silica cloth on the upper end face of the pre-treated forging stock. And pressing down at a deformation speed of 45mm/s and a deformation amount of 50%, pressing down for about 500mm, and performing second hot press forging to obtain a second forging stock. And opening the die, conveying the second forging stock to a resistance furnace to be heated for 2h, and then cooling to room temperature along with the resistance furnace to obtain an integrated composite stock.
Control group:
step S1, adopting an initial blank with a material of 508gr.3, wherein the size of the single initial blank is:
Figure BDA0002884076130000101
the single initial blank is formed by processing a continuous casting plate blank with the thickness of 200mm by a milling machine and a lathe, the milling machine and the lathe are adopted to remove rust layers and oxide layers on the upper and lower combined surfaces of the initial blank and the surface of a cylinder, the parallelism of the upper and lower surfaces to be welded of the initial blank is ensured, the verticality of the cylinder of the initial blank and the roughness of the upper and lower surfaces of the initial blank are 1.6 mu m, then the surface of the initial blank is cleaned by absolute ethyl alcohol or acetone, surface oil stains are removed, hot air is used for blow-drying (the temperature is controlled to be 30-50 ℃) to obtain a metal blank with a clean surface, and then 5 metal blanks with clean surfaces are vertically stacked and fixed by a clamp to obtain a prefabricated blank;
step S2, fixing the prefabricated blank on the vacuum electron beam welding worktable, moving into the vacuum chamber, vacuumizing, preparing formal welding when the vacuum degree of the vacuum chamber is less than or equal to 0.1Pa, and maintaining the welding vacuum degree at 5.0 x 10 during the formal welding-3-1.0×10-2Pa, welding acceleration voltage of 70kV, beam current of 220mA, focusing current of 580mA, welding seam depth of about 20mm, and obtaining a composite blank after assembly welding;
step S3, performing forging and pressing compounding by adopting a hydraulic press, putting the compound blank into a resistance furnace, heating to 1250 ℃ by adopting a two-stage heating process, and performing a first stage: rapidly raising the temperature from room temperature to 770 ℃ at 220 ℃/h, and in the second stage: slowly heating to 1250 ℃ from 770 ℃ at a speed of 150 ℃/h, preserving heat for 10h when reaching 1250 ℃, transferring the compound blank after heat preservation and thorough heat preservation to a press, pressing down at a deformation speed of 45mm/s and a deformation amount of 54 percent, pressing down for about 540mm, and then air-cooling to room temperature to obtain the integrated compound blank.
The experimental group and the control group are respectively dissected, the interface microstructure is analyzed, and the normal temperature and high temperature tensile analysis is carried out on the bonding interface of the blank edge position, and the result is shown in figures 4-8. FIGS. 4 (a) and (b) are the microstructure diagrams of the bonding interface of the experimental group and the control group of example 1, respectively; FIGS. 5 (a) and (b) are the fracture pattern of the tensile fracture and the high-power microstructure of the core of the tensile fracture of the experimental group of example 1 at room temperature, respectively; FIGS. 6 (a) and (b) are the fracture pattern of the tensile fracture at high temperature and the high-power microstructure pattern of the core of the tensile fracture in the experimental group of example 1, respectively; FIGS. 7 (a) and (b) are the fracture pattern of the tensile fracture and the high-power microstructure of the core of the tensile fracture in the control group of example 1 at room temperature, respectively; in FIG. 8, (a) and (b) are the fracture pattern of the tensile fracture at high temperature and the high-power microstructure pattern of the tensile fracture core of the control group in example 1, respectively.
As can be seen from (a) and (b) in fig. 4, the oxide at the bonding interface of the experimental group is dispersed, fine and almost disappeared, and the original initial interface is almost not seen from the high-power microstructure morphology. The fracture of the normal-temperature stretching and the fracture of the high-temperature stretching of the experimental group and the control group are not fractured at the bonding interface through measurement.
As can be seen from FIGS. 5-8, the fracture centers of the experimental groups at room temperature and high temperature are rough fibrous, and contain a large amount of dimples, which indicates that the plasticity is good; the core of the fracture at room temperature and high temperature in the control group is flat, and the shape of the dimple is still the same through high power analysis, but the dimple is shallow. The tensile property data at room temperature in table 1 show that the mechanical properties of the experimental groups are excellent. Therefore, the invention is more beneficial to interface compounding and oxide dispersion and fragmentation, enhances the homogenization degree and bonding strength of the interface and improves the material performance.
Meanwhile, the material properties of the prepared integrated composite blanks are tested, and the measurement results are shown in table 1, namely, the measurement results of the normal-temperature tensile properties at the bonding interface of the edge positions of the experimental group and the control group of the composite blanks in example 1.
TABLE 1
Figure BDA0002884076130000111
As can be seen from Table 1, the mechanical properties of the composite blanks of the experimental group are obviously superior to those of the control group, the tensile strength, the yield strength and the elongation after fracture are all improved, and the comprehensive properties of the integrated composite blanks prepared by the process are superior to those of the integrated composite blanks prepared by the prior art.
Example 2
The experimental group and the control group of example 2 have substantially the same steps S1 and S2 as example 1, except that the initial billet is different and the forging process of step S3 is different, as follows:
the experimental group used an initial billet of material 508gr.3, with the individual initial billet sizes:
Figure BDA0002884076130000121
the preparation of an integrated composite billet of 203 tons consists of 4 initial billets. A single initial blank is formed from
Figure BDA0002884076130000124
The billet is heated at high temperature (the heating temperature is 1250 ℃), cooled to room temperature after closed upsetting, and the single initial billet weighs about 51 tons. Subsequent machining to
Figure BDA0002884076130000125
Therefore, the integrated composite blank of 203 tons has 8 upper and lower surfaces and 4 column surfaces which are processed from 4 initial blanks.
The control group is prepared by processing an initial blank with the material of 508Gr.3 by selecting a continuous casting slab with the thickness of 250mm according to the prior artThe initial block blank size was:
Figure BDA0002884076130000122
for a 203 ton composite billet, 26 initial billet compositions are required. Therefore, the number of the upper and lower surfaces is 52, and the number of the column surface is 26. The differences in the surface cleaning and welding processes for the initial blanks for the experimental and control groups of example 2 are shown in table 2.
TABLE 2
Figure BDA0002884076130000123
The composite blanks of the experimental group and the control group are respectively forged in the following processes:
experimental groups:
step S3, performing forging and pressing compounding by adopting a hydraulic press, putting the compound blank into a resistance furnace, heating to 1250 ℃ by adopting a two-stage heating process, and performing a first stage: rapidly raising the temperature from room temperature to 770 ℃ at 250 ℃/h, and in the second stage: slowly heating from 770 ℃ to 1250 ℃ at a speed of 140 ℃/h, preserving heat for 10h when reaching 1250 ℃, transferring the compound blank after heat preservation to a press, pressing down at a deformation speed of 3mm/s and a deformation amount of 4%, pressing down for about 260mm, performing first hot press forging to obtain a first forging blank, then covering a layer of high silica cloth on the first forging blank, returning the first forging blank to a resistance furnace to heat to 1250 ℃ and preserving heat for 38h, moving the forging blank to be pretreated to the high silica cloth on a hot state base plate of the press after the forging blank is completely hot, preheating the base plate in advance, and measuring the surface temperature to about 550 ℃. The cylinder mould is sleeved into the pre-treatment forging stock, and then the cover plate which is preheated in advance is placed on the high silica cloth on the upper end face of the pre-treatment forging stock. The second hot press forging was performed by pressing down at a deformation rate of 40mm/s and a deformation amount of 46% to a press down of about 2990 mm. And opening the die, transferring the composite forging stock to a resistance furnace, and heating for 20 hours without deformation to obtain an integrated composite stock.
Control group:
step S3, performing forging and pressing compounding by adopting a hydraulic press, putting the compound blank into a resistance furnace, heating to 1250 ℃ by adopting a two-stage heating process, and performing a first stage: rapidly raising the temperature from room temperature to 770 ℃ at 250 ℃/h, and in the second stage: slowly heating to 1250 ℃ from 770 ℃ at a speed of 140 ℃/h, preserving heat for 45h when reaching 1250 ℃, transferring the compound blank after heat preservation and thorough heat preservation to a press, pressing down at a deformation speed of 40mm/s and a deformation amount of 50%, pressing down for about 3250mm, and not deforming again to obtain the integrated compound blank.
And (3) carrying out point-taking analysis on the combined surfaces of all layers of the integrated composite blank after forging and compounding, and respectively simulating and calculating the true strain conditions of 3 positions such as the central point, 1/2R, edge point and the like of 3 interfaces for an experimental group, wherein the point-selection distribution of the 3 interfaces is shown in figure 9. The first layer, the second layer, the third layer and the fourth layer from the lower surface are respectively selected as the control group, and the true strains at 3 positions such as a central point, an 1/2R point, an edge point and the like are respectively extracted, and a point drawing is shown in FIG. 10. The true strain distribution at each site of the experimental and control groups is shown in tables 3 and 4, respectively.
TABLE 3
Figure BDA0002884076130000131
TABLE 4
Figure BDA0002884076130000132
Figure BDA0002884076130000141
As seen from tables 3 and 4, compared with the simulated true strain of 0.693 of the integral composite blank, in the prior art, the minimum true strain of the first layer of the composite blank close to the upper and lower surfaces is only about 0.19, the maximum value is about 0.51, the true strain value of the second and third layers of the composite blank close to the upper and lower surfaces is far less than 0.693, the true strain point greater than 0.693 does not appear until the fourth layer of the composite blank close to the upper and lower surfaces, but the edge positions of the four layers are still in the hard deformation region. The real strain acquisition and analysis of each position shows that the deformation is extremely uneven in the prior art. However, by adopting the large-size metal blank, except that the true strain of the local edge point is smaller than the target value, the vast majority of true strains of 3 bonding interfaces are higher than the true strain of 0.693, so that the bonding strength of the interfaces is effectively ensured, the deformation is more uniform, and the method plays an important role in improving the quality of the integrated composite blank.
Although the present disclosure has been described above, the scope of the present disclosure is not limited thereto. Various changes and modifications may be effected therein by one of ordinary skill in the pertinent art without departing from the spirit and scope of the present disclosure, and these changes and modifications are intended to be within the scope of the present disclosure.

Claims (10)

1. A preparation method of a metal solid composite additive blank is characterized by comprising the following steps:
step S1, stacking and forming a plurality of initial blanks with clean surfaces to obtain a prefabricated blank;
step S2, welding the prefabricated blank to weld the bonding interfaces among the plurality of initial blanks to obtain a composite blank;
step S3, heating the composite blank to a first temperature T1And keeping the temperature, after reaching the temperature, at a deformation speed V1Deformation amount D1Carrying out first hot press forging to obtain a first forging stock, and then heating the first forging stock to a second temperature T2And preserving heat, and simultaneously heating the cover plate and the base plate to a third temperature T3And preserving heat, after the temperature is equalized, placing the first forging stock on the base plate, sleeving a mould on the first forging stock and the base plate, placing the cover plate on the first forging stock, and deforming at a speed V2Deformation amount D2Carrying out hot press forging for the second time to obtain a second forging stock, removing the die, and then heating the second forging stock to a fourth temperature T again4And preserving the heat until the temperature is reached to obtain an integrated composite blank; wherein, V2＞V1，D2＞D1。
2. The preparation method of the metal solid-solid composite additive blank according to claim 1Method, characterized in that in step S3, the deformation speed V is1Satisfies the following conditions: v is not more than 1mm/s1< 5mm/s, the deformation D1Satisfies the following conditions: 1% < D1Less than 5 percent; the deformation velocity V2Satisfies the following conditions: v is less than or equal to 10mm/s2Less than or equal to 60mm/s, the deformation D2Satisfies the following conditions: not less than 35 percent.
3. The method for preparing the metal-fixing composite additive blank according to claim 1, wherein the height of the first forging blank + the height of the backing plate < the height of the die < the height of the first forging blank + the height of the backing plate + the height of the cover plate.
4. The method of claim 1, wherein in step S3, the mold has a cylindrical shape.
5. The method according to claim 4, wherein the diameter of the cover plate is smaller than the diameter of the die, the diameter of the backing plate is larger than the diameter of the lower end surface of the first forged blank, and the diameter of the cover plate is larger than the diameter of the upper end surface of the first forged blank.
6. The method of claim 1, wherein the first temperature T is greater than the first temperature T1Tm is more than or equal to 0.7, and the second temperature T2Tm is more than or equal to 0.7Tm, and the third temperature T is more than or equal to 0.5Tm3Tm is more than or equal to 0.25, and the fourth temperature T4≥0.7Tm。
7. The method for preparing a metal solid-solid composite additive blank according to claim 1, wherein the first temperature T3 is set as the first temperature T1The holding time of (1) is more than 1h, and the second temperature T2The holding time of (a) is more than 10h, and the third temperature T3The heat preservation time is more than 10h, and the fourth temperature T4While keeping warmThe time is more than 2 h.
8. The method for preparing a metal solid-solid composite additive manufactured blank according to any one of claims 1 to 7, wherein the mass of the initial blank in the step S1 is not less than 20 tons.
9. The method for preparing a metal solid composite additive blank according to any one of claims 1 to 7, wherein in step S1, the shape of the initial blank is cylindrical.
10. The method for preparing the metal solid-solid composite additive blank according to any one of claims 1 to 7, wherein in the step S2, the welding mode adopts vacuum electron beam welding, and the parameters of the vacuum electron beam welding are as follows: the degree of vacuum was 5.0X 10-3Pa-1.0×10-2Pa, acceleration voltage: greater than 50KV, beam current: greater than 200mA, focus current: greater than 500mA, power: greater than 10KW, welding rate: v is more than 50mm/s and less than 300 mm/s.
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Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002254132A (en) * 2001-02-28 2002-09-10 Kikusui Forging Co-Op Hot forging and forming method for magnesium alloy member
CN105642804A (en) * 2016-02-03 2016-06-08 中南大学 Forging method for improving evenness of structures of large-size magnesium alloy forged discs
CN106270325A (en) * 2016-08-09 2017-01-04 同济大学 A kind of cladding method being applicable to Ti Al series intermetallic compound isothermal forging
CN109604926A (en) * 2018-11-14 2019-04-12 中国原子能科学研究院 Steel blank constructs interface healing method
CN110802189A (en) * 2019-11-12 2020-02-18 中航上大高温合金材料有限公司 Forging process for high-temperature alloy plate blank difficult to deform
CN111036812A (en) * 2019-12-27 2020-04-21 天津重型装备工程研究有限公司 Method for controlling oxide on bonding interface of metal composite product
CN111496160A (en) * 2020-04-28 2020-08-07 北京钢研高纳科技股份有限公司 Forging method for improving end surface structure of high-temperature alloy ingot blank, application of forging method and high-temperature alloy forging blank

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2002254132A (en) * 2001-02-28 2002-09-10 Kikusui Forging Co-Op Hot forging and forming method for magnesium alloy member
CN105642804A (en) * 2016-02-03 2016-06-08 中南大学 Forging method for improving evenness of structures of large-size magnesium alloy forged discs
CN106270325A (en) * 2016-08-09 2017-01-04 同济大学 A kind of cladding method being applicable to Ti Al series intermetallic compound isothermal forging
CN109604926A (en) * 2018-11-14 2019-04-12 中国原子能科学研究院 Steel blank constructs interface healing method
CN110802189A (en) * 2019-11-12 2020-02-18 中航上大高温合金材料有限公司 Forging process for high-temperature alloy plate blank difficult to deform
CN111036812A (en) * 2019-12-27 2020-04-21 天津重型装备工程研究有限公司 Method for controlling oxide on bonding interface of metal composite product
CN111496160A (en) * 2020-04-28 2020-08-07 北京钢研高纳科技股份有限公司 Forging method for improving end surface structure of high-temperature alloy ingot blank, application of forging method and high-temperature alloy forging blank

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
张建国等: "大型焊接试验转子锻造工艺研究 ", 《大型铸锻件》 *
张心金等: "中间夹层在金属复合板制造过程中的应用 ", 《轧钢》 *

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