阅读说明：本技术 增大难变形合金模锻件表层变形的波浪形坯料设计方法 (Design method of wavy blank for increasing surface deformation of alloy die forging difficult to deform ) 是由 赵张龙 曹澜川 徐文馨 郭鸿镇 于 2020-07-03 设计创作，主要内容包括：本发明涉及一种增大难变形合金模锻件表层变形的波浪形坯料设计方法,是以难变形合金模锻件的性能需求来确定合金模锻条件下需求的变形量,采用模锻原理根据模锻件形状设计波浪形坯料,然后进行波浪形坯料的模锻成形模拟,计算不同部位的变形量,对比变形量计算结果修正波浪形坯料尺寸,最后确定出合理的波浪形坯料。该设计方法可以改变难变形合金模锻件表层部位的变形,获得表层部位与中心部位一致的性能,在锻造生产上具有推广应用价值。(The invention relates to a method for designing a wavy blank for increasing the surface deformation of an alloy die forging piece difficult to deform, which is characterized in that the deformation required under the alloy die forging condition is determined according to the performance requirement of the alloy die forging piece difficult to deform, the wavy blank is designed according to the shape of the die forging piece by adopting the die forging principle, then the die forging forming simulation of the wavy blank is carried out, the deformation of different parts is calculated, the size of the wavy blank is corrected by comparing the calculation result of the deformation, and finally, the reasonable wavy blank is determined. The design method can change the deformation of the surface part of the alloy die forging piece difficult to deform, obtain the performance of the surface part consistent with that of the central part, and has popularization and application values in forging production.)

1. A design method of a wavy blank for increasing the surface deformation of an alloy die forging difficult to deform is characterized by comprising the following steps:

step 1, deformation determination: carrying out a physical simulation die forging test on the alloy for the die forging piece on a press machine or air hammer forging equipment, wherein the physical simulation die forging test is consistent with the actual forging temperature range, testing the tensile and creep properties of the alloy after being forged by 15-70% deformation, and determining the deformation range required by the die forging piece to reach the performance standard according to the corresponding relation between the deformation and the performance;

step 2, designing a wavy blank: the upper end surface and the lower end surface of the blank are designed to be wavy before die forging, the height h1 from the wave crest to the wave trough of the upper end surface and the height h2 from the wave crest to the wave trough of the lower end surface are not less than 5 percent of the total height of the blank, the included angle A of the wave crest of the upper end surface and the included angle B of the wave crest of the lower end surface are in the range of 60-150 degrees, and the upper wave and the lower wave are continuously, discontinuously and symmetrically distributed;

step 3, deformation calculation: converting the shape and size of the wavy blank designed in the step 2 into blank input of finite element simulation software such as Deform, Abaqus and the like, setting forging parameters to perform die forging forming simulation calculation on the blank in the step 2, and reading deformation of different parts of the surface layer and the center of the blank after die forging forming designed in the step 2 from the software simulation calculation result;

step 4, modifying and determining the size of the wavy blank: and (3) comparing the deformation read from the simulation calculation result in the step (3) with the deformation range determined in the step (1), if the deformation calculated in the step (3) is within the deformation range determined in the step (1), the shape and size of the blank designed in the step (2) can be used for actual die forging forming, and otherwise, repeating the steps (2) to (4) until a reasonable wavy blank is determined.

Technical Field

The invention belongs to the field of forging and processing of alloy difficult to deform, and relates to a design method of a wavy blank for increasing surface deformation of an alloy die forging difficult to deform.

Background

In the die forging forming process of the alloy forging which is difficult to deform, because the contact area of the surface layer of the blank and a die is large, the surface layer of the blank is seriously cooled and has large friction resistance, so that metal on the surface layer of the blank flows difficultly, a deformation dead zone which is not deformed or deforms very little is formed, dynamic recrystallization of the deformation dead zone is difficult to occur, crystal grains are difficult to refine, and the performance is often unqualified. Before the existing die forging production of the alloy which is difficult to deform, a lubricant is generally uniformly coated on the surface layer of a blank to reduce the temperature drop and the friction coefficient so as to improve the fluidity of the alloy in the die forging process. Although the existing technology for reducing the friction coefficient by adopting the lubricant can reduce the deformation dead zone, the deformation dead zone can not be completely eliminated, and after some difficultly-deformed alloy blanks are subjected to die forging forming, a thicker deformation dead zone still exists on the surface layer of a die forging piece. Because the deformation degree difference between the surface deformation dead zone and the central large deformation zone of the die forging is large, the structure and the performance of a plurality of alloy materials difficult to deform are very sensitive to deformation process parameters, and the deformation of different degrees can cause the difference between the structure and the performance of the surface deformation dead zone and the central large deformation zone. When the difference between the structure and the performance of the surface layer and the central part of the forging is too large, the uniformity of different parts can be seriously influenced, and the use requirement can not be met. Therefore, the deformation of the surface layer part of the alloy forging which is difficult to deform needs to be strictly controlled to ensure the overall uniform performance of the final component.

4. Objects of the invention

The problem that the performance of a surface deformation dead zone and the performance of a central part of a traditional die forging are inconsistent is solved, and the problem is a difficult problem in actual production. The internal structure can be changed and the performance can be improved by increasing the deformation of the surface part of the alloy die forging piece difficult to deform, but how to reduce the friction force between the blank and the die from the aspect of practical production feasibility so as to improve the deformation of the surface part is a key important ring in the die forging process of the alloy difficult to deform.

Disclosure of Invention

Technical problem to be solved

In order to avoid the defects of the prior art, the invention provides a design method of a wavy blank for increasing the surface deformation of a difficult-to-deform alloy die forging, which improves the performance of the surface part of the difficult-to-deform alloy die forging and effectively increases the deformation of the surface part, so that the deformation of the surface part is changed to obtain the performance consistent with that of the central part, and the requirement of the performance consistency of different parts of the difficult-to-deform alloy die forging is met.

Technical scheme

A design method of a wavy blank for increasing the surface deformation of an alloy die forging difficult to deform is characterized by comprising the following steps:

step 1, deformation determination: carrying out a physical simulation die forging test on the alloy for the die forging piece on a press machine or air hammer forging equipment, wherein the physical simulation die forging test is consistent with the actual forging temperature range, testing the tensile and creep properties of the alloy after being forged by 15-70% deformation, and determining the deformation range required by the die forging piece to reach the performance standard according to the corresponding relation between the deformation and the performance;

step 2, designing a wavy blank: the upper end surface and the lower end surface of the blank are designed to be wavy before die forging, the height h1 from the wave crest to the wave trough of the upper end surface and the height h2 from the wave crest to the wave trough of the lower end surface are not less than 5 percent of the total height of the blank, the included angle A of the wave crest of the upper end surface and the included angle B of the wave crest of the lower end surface are in the range of 60-150 degrees, and the upper wave and the lower wave are continuously, discontinuously and symmetrically distributed;

step 3, deformation calculation: converting the shape and size of the wavy blank designed in the step 2 into blank input of finite element simulation software such as Deform, Abaqus and the like, setting forging parameters to perform die forging forming simulation calculation on the blank in the step 2, and reading deformation of different parts of the surface layer and the center of the blank after die forging forming designed in the step 2 from the software simulation calculation result;

step 4, modifying and determining the size of the wavy blank: and (3) comparing the deformation read from the simulation calculation result in the step (3) with the deformation range determined in the step (1), if the deformation calculated in the step (3) is within the deformation range determined in the step (1), the shape and size of the blank designed in the step (2) can be used for actual die forging forming, and otherwise, repeating the steps (2) to (4) until a reasonable wavy blank is determined.

Advantageous effects

The invention provides a method for designing a wavy blank for increasing the surface deformation of an alloy die forging piece difficult to deform, which is characterized in that the deformation required under the alloy die forging condition is determined according to the performance requirement of the alloy die forging piece difficult to deform, the wavy blank is designed according to the shape of the die forging piece by adopting the die forging principle, then the die forging forming simulation of the wavy blank is carried out, the deformation of different parts is calculated, the size of the wavy blank is corrected by comparing the calculation result of the deformation, and finally, the reasonable wavy blank is determined.

According to the die forging design principle, on the basis of the original blank design, the wavy shape design is added on the contact part of the blank and the die, so that the deformation of the surface part of the die forging can be effectively increased, and the problem that the performance of the surface deformation dead zone is inconsistent with that of the central part of the traditional die forging is solved. Compared with the design principle of a common die forging, the design method comprises the steps of 1, firstly determining the deformation amount required by the performance of the alloy difficult to deform, groping the deformation amount required by the die forging deformation through an alloy die forging test and a test, and determining the main factors of performance control in the alloy die forging process. And 2, designing the upper surface and the lower surface of the blank into wave shapes, so that the large-area contact between the blank and a die is reduced, the flowability of the blank in the die forging process is improved, the deformation of the surface layer part is effectively increased, and the wave size and distribution can be changed according to the shape of the forged piece to adapt to different shapes of the forged piece. And 3, calculating the deformation of the surface part through finite element simulation, and analyzing the die forging forming effect of the designed wavy blank so as to improve the production efficiency and ensure the product quality. And step 4, modifying and determining the shape and the size of the wavy blank until the die forging production can be carried out.

The design method can change the deformation of the surface part of the alloy die forging piece difficult to deform, obtain the performance of the surface part consistent with that of the central part, and has popularization and application values in forging production.

Drawings

FIGS. 1 to 2: the invention is a schematic illustration of the steps

FIG. 3: comparison of die forging results of common blank (left) and wavy blank (right) 1

FIG. 4: comparison of die forging results of common blank (left) and wavy blank (right) 2

FIG. 5: comparison of die forging results of common blank (left) and wavy blank (right) 3

Detailed Description

The invention will now be further described with reference to the following examples and drawings:

a design method of a wavy blank for increasing the surface deformation of an alloy die forging difficult to deform comprises the following steps:

(1) and (3) deformation amount determination: carrying out a physical simulation test (figure 1(a)) of the alloy die forging, carrying out forging deformation in a deformation range of 15-70% (figure 1(b)), testing performance data under different deformation parameters, and determining the deformation amount (figure 1(c)) of the die forging deformation reaching the performance requirement;

(2) designing a wavy blank: according to the die forging principle, the upper end face and the lower end face of a blank are designed into wave shapes, the height h1 from the wave crest to the wave trough of the upper end face and the height h2 from the wave crest to the wave trough of the lower end face are not less than 5% of the total height of the blank, the included angle A between the wave crest of the upper end face and the included angle B between the wave crest of the lower end face are 60-150 degrees, the upper wave shape and the lower wave shape can be continuously, discontinuously and symmetrically distributed, and the die forging piece is determined according to the shape and the size of a die forging piece (figure;

(3) and (3) deformation calculation: performing die forging forming numerical simulation calculation on the wavy blank designed in the step 2 within the die forging parameter range of the alloy by using finite element simulation software (fig. 2(b)), reading deformation of different parts of the surface layer and the center of the blank designed in the step 2 after die forging forming from a simulation result, and observing the difference of the surface layer part and the center part (fig. 2 (c));

(4) modifying and determining the size of the wavy blank: and (3) comparing and analyzing the deformation (figure 2(c)) read from the simulation calculation result of the step (3) with the deformation (figure 1(c)) determined in the step (1), if the requirements are met, the shape and the size of the wavy blank designed in the step (2) can be used for actual die forging forming, and otherwise, repeating the steps (2) to (4) until a reasonable wavy blank is determined.

The design method of the wavy blank solves the problem of deformation dead zone of the surface part in the die forging process of the alloy material difficult to deform, and increases the deformation of the surface part, refines crystal grains and improves the performance.

Example 1: the method comprises the following steps of 1, determining the deformation of the GH4169 alloy, obtaining the change relation of the alloy performance along with deformation parameters through a die forging physical test in a deformation range of 15-70%, and determining that the deformation of the die forging deformation to reach the required performance is not less than 0.35; step 2, designing a wavy blank, wherein the upper end face and the lower end face of the blank are designed into wavy shapes on the basis of die forging principle design, the height sizes h1 and h2 of the wavy shapes are 10% of the total height of the blank, the angle A and the angle B are 90 degrees, and the wavy shapes are distributed in a continuous mode; step 3, calculating deformation, carrying out finite element simulation on the die forging process of the designed wavy blank, obtaining the deformation of different parts of the blank in the post-simulation treatment process, and finding that the equivalent deformation of the surface part and the central part exceeds 1; and 4, modifying and determining the size of the blank, comparing the deformation amount obtained by the simulation calculation in the step 3 with the deformation amount required in the step 1, finding that the equivalent deformation amount of the surface part is far more than the minimum deformation amount of 0.35 determined in the step 1, meeting the requirement, and performing die forging forming on the designed wavy blank. Fig. 3 is a comparison of the die forging results of the common blank (left) and the wavy blank (right), and it can be seen that the deformation of the surface portion of the forged piece after the die forging of the common blank is very small, while the deformation of the surface portion of the die forged piece after the die forging of the wavy blank is large, and the crystal grains can be obviously improved.

Example 2: the method comprises the following steps of 1, determining the deformation of the GH4169 alloy, obtaining the change relation of the alloy performance along with deformation parameters through a die forging physical test in a deformation range of 15-70%, and determining that the deformation of the die forging deformation to reach the required performance is not less than 0.35; step 2, designing a wavy blank, wherein the upper end face and the lower end face of the blank are designed into wavy shapes on the basis of die forging principle design, the height sizes h1 and h2 of the wavy shapes are 15% of the total height of the blank, the angle A and the angle B are 60 degrees, and the wavy shapes are distributed in a continuous mode; step 3, calculating deformation, carrying out finite element simulation on the die forging process of the designed wavy blank, obtaining the deformation of different parts of the blank in the post-simulation treatment process, and finding that the equivalent deformation of the surface part and the central part exceeds 0.6; and 4, modifying and determining the size of the blank, comparing the deformation amount obtained by the simulation calculation in the step 3 with the deformation amount required in the step 1, finding that the equivalent deformation amount of the surface part far exceeds the minimum deformation amount by 0.35, meeting the requirement, and performing die forging forming on the designed wavy blank. Fig. 4 is a comparison of the die forging results of the common blank (left) and the wavy blank (right), and it can be seen that the deformation of the surface portion of the forged piece after the die forging of the common blank is very small, while the deformation of the surface portion of the die forged piece after the die forging of the wavy blank is large, and the crystal grains can be obviously improved.

Example 3: the method comprises the following steps of 1, determining the deformation of the GH4169 alloy, obtaining the change relation of the alloy performance along with deformation parameters through a die forging physical test in a deformation range of 15-70%, and determining that the deformation of the die forging deformation to reach the required performance is not less than 0.35; step 2, designing a wavy blank, wherein the upper end face and the lower end face of the blank are designed into wavy shapes on the basis of die forging principle design, the height sizes h1 and h2 of the wavy shapes are 15% of the total height of the blank, the angle A and the angle B are 120 degrees, and the wavy shapes are distributed in a continuous mode; step 3, calculating deformation, carrying out finite element simulation on the die forging process of the designed wavy blank, obtaining the deformation of different parts of the blank in the post-simulation treatment process, and finding that the equivalent deformation of the surface part and the central part exceeds 1; and 4, modifying and determining the size of the blank, comparing the deformation amount obtained by the simulation calculation in the step 3 with the deformation amount required in the step 1, finding that the equivalent deformation amount of the surface part far exceeds the minimum deformation amount by 0.35, meeting the requirement, and performing die forging forming on the designed wavy blank. Fig. 5 is a comparison of the die forging results of the common blank (left) and the wavy blank (right), and it can be seen that the deformation of the surface portion of the forged piece after the die forging of the common blank is very small, while the deformation of the surface portion of the die forged piece after the die forging of the wavy blank is large, and the crystal grains can be obviously improved.