CN113836715B - Forging deformation process test method - Google Patents

Abstract

The invention provides a forging deformation process test method, which comprises the following steps: A. performing numerical simulation on the bar upsetting process to obtain the equivalent strain field distribution condition of the forging; B. determining a region with the same deformation amount as the engineering deformation amount corresponding to the equivalent strain field according to the strain field distribution condition, and determining a sampling region in the region; C. repeating step A, B to obtain a proper bar diameter and thickness and a sampling area; D. c, blanking according to the diameter and thickness of the bar obtained in the step C, and forging a upsetting cake according to the set deformation to obtain a forging piece; E. sampling in a sampling area and carrying out mechanical property test to obtain the relation between the deformation and the tissue property. The invention samples and detects in the sampling area with the deformation corresponding to the equivalent strain field and the engineering deformation being uniform and consistent, avoids the influence of different deformation on the tissue performance, and can accurately establish the relationship between the deformation and the tissue performance so as to guide the actual production and obtain the optimal tissue performance of the forging.

Description

Forging deformation process test method

Technical field

The invention relates to the technical field of forging testing, in particular to a forging deformation process testing method.

Background technique

In order to obtain the best structural properties for metal material forgings such as titanium alloys, steels and high-temperature alloys, especially new metal material forgings, it is usually necessary to conduct forging process experiments and studies to obtain the best forging process parameters. Existing forging deformation process tests often need to first calculate the engineering deformation, and then use numerical simulation to calculate the equivalent variables, find out the corresponding relationship between the engineering strain and the equivalent strain, and determine the appropriate deformation window. For tests with complex deformation processes, , it is often difficult to accurately judge the amount of deformation or equivalent strain, and it is even more difficult to establish the relationship between the amount of deformation and tissue properties, which often results in test results that may deviate from the actual rules.

Contents of the invention

The technical problem to be solved by the present invention is to provide a forging deformation process test method that can easily establish the corresponding relationship between engineering strain and equivalent strain, thereby accurately establishing the relationship between deformation amount and structural properties to guide actual production and obtain the best forging structure. performance.

The technical solution adopted by the present invention to solve the technical problem is: a forging deformation process test method, which includes the following steps:

A. Select the bar as the test material and conduct a numerical simulation of the bar forging process. After the forging deformation reaches the engineering deformation amount, the equivalent strain field distribution of the forging is obtained;

B. According to the distribution of the strain field, determine the area where the deformation amount corresponding to the equivalent strain field is the same as the engineering deformation amount, and determine the sampling area within this area;

C. Repeat steps A and B, repeatedly optimize and iterate during the numerical simulation process to obtain the appropriate bar diameter and thickness, and obtain a sampling area where the deformation amount corresponding to the equivalent strain field is uniform and consistent with the engineering deformation amount;

D. Cut the material according to the diameter and thickness of the bar obtained in step C, and perform upsetting forging according to the set deformation amount to obtain the forging;

E. Take samples from the forgings and conduct mechanical property tests. The sampling location is located in the sampling area in step C;

F. Based on the statistical analysis of the mechanical property test results, the relationship between deformation and organizational properties is obtained, the best performance is identified, and the optimal forging deformation process parameters are determined.

Further, in step A, the diameter of the bar is greater than or equal to 200mm, and the length is greater than or equal to 50mm.

Further, in step A, the engineering deformation amount is 10% to 80%.

The beneficial effects of the present invention are: the present invention conducts sampling and detection in a sampling area where the deformation amount corresponding to the equivalent strain field is uniform and consistent with the engineering deformation amount, avoiding the impact of different deformation amounts on tissue performance, and can accurately establish the deformation amount and tissue performance relationship to guide actual production and obtain the best structural properties of forgings.

Description of the drawings

Figure 1 is a schematic diagram of the bar;

Figure 2 is a schematic diagram of the forging after deformation;

Figure 3 is a schematic distribution diagram of the cross-sectional equivalent strain field corresponding to 20% engineering deformation in the example of the present invention;

Figure 4 is a schematic diagram of the sampling area corresponding to 20% engineering deformation in the example of the present invention;

Figure 5 is a schematic distribution diagram of the cross-sectional equivalent strain field corresponding to 50% engineering deformation in the example of the present invention;

Figure 6 is a schematic diagram of the sampling area corresponding to 50% engineering deformation in the example of the present invention.

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings and examples.

The forging deformation process test method of the present invention includes the following steps:

A. Select the bar as the test material. As shown in Figure 1, the diameter of the bar is greater than or equal to 200mm and the length is greater than or equal to 50mm. The most common upsetting forging is used to test the deformation of the material.

Numerical simulation is performed on the bar forging process. After the forging deformation reaches the engineering deformation amount, the forging is obtained as shown in Figure 2. The equivalent strain field distribution of the forging is determined. The engineering deformation amount can be between 10% and 80%. . Numerical simulation is carried out in numerical simulation software, which can simulate the forging process of bars. Various parameters such as bar size, forging deformation, forging pressure, forging temperature, etc. can be easily adjusted to obtain forgings with different properties. In addition, the numerical simulation software can also automatically generate the equivalent strain field distribution map of the forging.

B. According to the strain field distribution of the forging, determine the area where the deformation amount corresponding to the equivalent strain field is the same as the engineering deformation amount, and determine the sampling area within this area. Since numerical simulation simulates the forging process under ideal conditions, and the actual forging process is affected by friction and other factors, there is a certain difference between the numerical simulation and the actual forging situation, making the deformation amount corresponding to the equivalent strain field different from the engineering deformation amount. They cannot be exactly the same. Therefore, the area where the deformation amount corresponding to the effect strain field is the same as the engineering deformation amount is manually determined.

C. Repeat steps A and B, repeatedly optimize and iterate during the numerical simulation process to obtain the appropriate bar diameter and thickness, and obtain a sampling area where the deformation amount corresponding to the equivalent strain field is uniform and consistent with the engineering deformation amount. That is, the diameter and thickness of the bar and other forging process parameters are adjusted multiple times to obtain better forging process parameters, and the sampling area is ensured by repeatedly determining the deformation amount corresponding to the equivalent strain field and the engineering deformation amount to be uniform. The accuracy and size of the sampling area meet the sampling requirements. In addition, the sampling areas corresponding to various engineering deformations can also be determined.

D. Cut the bar according to the diameter and thickness obtained in step C, and perform upsetting forging according to the set deformation amount to obtain the forging. The forging process is the same as that obtained by the optimization iteration in step C, which reduces the error between numerical simulation and actual forging and improves the accuracy of the test.

E. Take samples from the forgings and conduct mechanical property tests. The sampling location is located in the sampling area in step C. By sampling in a sampling area where the deformation amount corresponding to the equivalent strain field is consistent with the engineering deformation amount, the influence of various factors in the actual forging process on the sample performance is eliminated, and the engineering deformation amount and the equivalent strain field of the sample are ensured. The corresponding deformation amount is uniform, avoiding the influence of different deformation amounts on the structural properties. The relationship between the deformation amount and the structural properties can be accurately established to guide actual production and obtain the best structural properties of forgings.

F. Based on the statistical analysis of the mechanical property test results, the relationship between deformation and organizational properties is obtained, the best performance is identified, and the optimal forging deformation process parameters are determined.

The present invention will be further explained below by taking a certain TB18 titanium alloy as an example.

Embodiment 1

A. Select the bar as the test material, conduct a numerical simulation of the bar forging process, set the engineering deformation amount to 20%, and obtain the equivalent strain field distribution of the forging after the forging deformation reaches the engineering deformation amount;

B. According to the distribution of the strain field, determine the area where the deformation amount corresponding to the equivalent strain field is the same as the engineering deformation amount, and determine the sampling area within this area;

C. Repeat steps A and B, and repeatedly optimize and iterate during the numerical simulation process to obtain the bar specification of φ300×70mm. The bar thickness is deformed from 70mm to 56mm to reach the set engineering deformation amount, and the forging shown in Figure 3 is obtained. The equivalent strain field distribution diagram of The area where the effective strain is between 0.218 and 0.243 is used as the sampling area. The sampling area is shown in Figure 4 and is circular.

D. Saw the TB18 titanium alloy bar φ300×70mm. The thickness tolerance of the bar after sawing is controlled within ±1mm. Use the forging process optimized in step C to forge the bar until the thickness of the bar is reduced. to 56mm, at which time the engineering deformation is 20%.

E. Heat treat the forgings, then take samples in the sampling area as shown in Figure 4, and conduct mechanical property tests on the samples.

F. Based on the statistical analysis of the mechanical property test results, the relationship between deformation and organizational properties is obtained, the best performance is identified, and the optimal forging deformation process parameters are determined.

Embodiment 2

A. Select the bar as the test material, conduct a numerical simulation of the bar forging process, set the engineering deformation to 50%, and obtain the equivalent strain field distribution of the forging after the forging deformation reaches the engineering deformation;

B. According to the distribution of the strain field, determine the area where the deformation amount corresponding to the equivalent strain field is the same as the engineering deformation amount, and determine the sampling area within this area;

C. Repeat steps A and B, and repeatedly optimize and iterate during the numerical simulation process to obtain the bar specification of φ300×70mm. The bar thickness is deformed from 70mm to 35mm to reach the set engineering deformation amount, and the forging shown in Figure 5 is obtained. The equivalent strain field distribution diagram of The area where the effective strain is between 0.705 and 0.734 is used as the sampling area. The sampling area is shown in Figure 6 and is circular.

D. Saw the TB18 titanium alloy bar φ300×70mm. The thickness tolerance of the bar after sawing is controlled within ±1mm. Use the forging process optimized in step C to forge the bar until the thickness of the bar is reduced. to 35mm, at which time the engineering deformation is 50%.

E. Heat treat the forgings, then take samples in the sampling area as shown in Figure 6, and conduct mechanical property tests on the samples.

F. Based on the statistical analysis of the mechanical property test results, the relationship between deformation and organizational properties is obtained, the best performance is identified, and the optimal forging deformation process parameters are determined.

The above descriptions are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and changes. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention shall be included in the protection scope of the present invention.

Claims (3)

1. The forging deformation process test method is characterized by comprising the following steps of:

A. selecting a bar as a test material, performing numerical simulation on a bar upsetting process, and obtaining the equivalent strain field distribution condition of the forging after upsetting deformation reaches engineering deformation;

B. determining a region with the same deformation amount as the engineering deformation amount corresponding to the equivalent strain field according to the strain field distribution condition, and determining a sampling region in the region;

C. repeating the step A, B, and adjusting the diameter and the thickness of the bar stock for a plurality of times in the numerical simulation process to obtain the proper diameter and the thickness of the bar stock, and obtaining a sampling area with the deformation corresponding to the equivalent strain field and the engineering deformation being uniform and consistent;

D. c, blanking according to the diameter and thickness of the bar obtained in the step C, and forging a upsetting cake according to the set deformation to obtain a forging piece;

E. c, sampling on the forging piece and carrying out mechanical property test, wherein the sampling position is positioned in the sampling area in the step C;

F. and according to the statistical analysis of the mechanical property test result, obtaining the relation between the deformation and the tissue property, identifying the optimal performance, and determining the technological parameters of the optimal forging deformation.

2. The forging deformation process test method as recited in claim 1, wherein: in the step A, the diameter of the bar stock is larger than or equal to 200mm, and the length is larger than or equal to 50mm.

3. The forging deformation process test method as recited in claim 1, wherein: in the step A, the engineering deformation amount is 10 to 80 percent.