阅读说明：本技术 一种利用金属材料内耗测定再结晶温度的方法 (Method for measuring recrystallization temperature by utilizing internal consumption of metal material ) 是由 方前锋 陈天禄 刘瑞 孙孟 谢卓明 蒋卫斌 王先平 吴学邦 刘长松 于 2021-08-06 设计创作，主要内容包括：本发明公开了一种利用金属材料内耗测定再结晶温度的方法,涉及金属材料无损检测技术领域,包括以下步骤：将冷变形金属材料试样安装到内耗测量仪上；将试样以恒定升温速率连续升温再随炉冷却,测试不同频率下的内耗值,绘制温度内耗曲线,得到再结晶内耗峰峰温；改变恒定升温速率,重复上述步骤,获得不同恒定升温速率下的再结晶内耗峰峰温；利用Kissinger方程对恒定升温速率及其对应的再结晶内耗峰峰温拟合分析,确定再结晶动力学参数；通过再结晶过程中,恒定升温速率与退火时间的等效关系,并结合前述确定的再结晶动力学参数,利用Kissinger方程得到传统等温退火的再结晶温度。本发明只需少量样品即可测定金属材料的再结晶温度,测试更简便、快速、可靠。(The invention discloses a method for measuring recrystallization temperature by utilizing internal consumption of a metal material, which relates to the technical field of nondestructive testing of the metal material and comprises the following steps: mounting the cold deformation metal material sample on an internal friction measuring instrument; continuously heating the sample at a constant heating rate, cooling the sample along with the furnace, testing internal consumption values at different frequencies, and drawing a temperature internal consumption curve to obtain a recrystallization internal consumption peak-to-peak temperature; changing the constant temperature rise rate, and repeating the steps to obtain the peak temperature of the internal consumption peak of the recrystallization at different constant temperature rise rates; fitting and analyzing the constant temperature rise rate and the corresponding recrystallization internal consumption peak temperature by using a Kissinger equation to determine a recrystallization kinetic parameter; and obtaining the recrystallization temperature of the traditional isothermal annealing by using the Kissinger equation through the equivalent relation between the constant temperature rise rate and the annealing time in the recrystallization process and combining the determined recrystallization kinetic parameters. The method can measure the recrystallization temperature of the metal material by only a small amount of samples, and the measurement is simpler, more convenient, quicker and more reliable.)

1. A method for measuring recrystallization temperature by using internal consumption of a metal material is characterized by comprising the following steps:

s1, obtaining a cold deformation metal material sample, and mounting the cold deformation metal material sample on an internal friction measuring instrument;

s2, continuously heating the cold deformation metal material sample from room temperature at a constant heating rate, cooling the cold deformation metal material sample to room temperature along with a furnace, testing the internal consumption values of the cold deformation metal material sample at different frequencies, drawing temperature internal consumption curves in the heating and cooling processes at different frequencies by taking the temperature as an X axis and the internal consumption value as a Y axis, determining a recrystallization internal consumption peak, and obtaining the recrystallization internal consumption peak temperature at the constant heating rate;

s3, changing the constant heating rate, repeating the step S2 to obtain temperature internal consumption curves at different constant heating rates, and obtaining recrystallization internal consumption peak and peak temperatures at different constant heating rates;

s4, utilizing Kissinger equation to perform fitting analysis on multiple groups of constant heating rates and corresponding recrystallization internal consumption peak temperatures, and determining recrystallization kinetic parameters of the metal material;

s5, obtaining the recrystallization temperature of the traditional isothermal annealing by combining the equivalent relationship between the constant temperature rise rate of continuous temperature rise in the internal friction measuring process and the annealing time of the isothermal annealing in the measuring process of a metallographic method or a hardness method in the recrystallization process and the recrystallization kinetic parameters determined in the step S4 and by using a Kissinger equation.

2. The method for measuring a recrystallization temperature using internal consumption of a metallic material according to claim 1, wherein in S2, the peak of internal consumption in recrystallization is determined based on a non-relaxivity characteristic of the peak of internal consumption and a disappearance characteristic of the peak of internal consumption during temperature reduction; the non-relaxivity of the internal consumption peak refers to the characteristic that the peak temperature of the internal consumption peak does not change along with the measurement frequency.

3. The method for measuring a recrystallization temperature using an internal loss of a metallic material as claimed in claim 1, wherein the constant temperature increase rate in S2 and S3 is 1 ℃/min or more.

4. The method for measuring a recrystallization temperature using an internal loss of a metallic material according to claim 1,the Kissinger equation is:where θ is the constant rate of temperature rise, T_mIs the peak temperature of internal consumption peak of recrystallization, E is the equivalent activation energy, R is the ideal gas constant, C is a constant independent of theta and temperature; and in S4, performing fitting analysis on the multiple groups of constant heating rates and corresponding recrystallization internal consumption peak temperatures to determine C and E values.

5. The method of claim 1, wherein the equivalent relationship between the constant temperature-raising rate of the continuous temperature-raising and the annealing time of the isothermal annealing in S5 is a common correspondence obtained by a numerical analysis method: the isothermal annealing time is 10min, 20min, 30min and 60min respectively corresponding to constant heating rate of 0.2 ℃/min, 0.14 ℃/min, 0.064 ℃/min and 0.034 ℃/min.

6. The method of claim 1, wherein the internal friction value is measured in S2 using a forced vibration mode at a frequency of 0.1-10 Hz.

7. The method for determining a recrystallization temperature using an internal friction of a metallic material as claimed in claim 1, wherein the shear strain amplitude of the internal friction value test is 10 in S2^-6～10^-4。

8. The method for measuring a recrystallization temperature using an internal loss of a metallic material as claimed in claim 1, wherein in S1, the specifications of the cold-deformed metallic material sample are: the length is 50-80 mm, the width is 0.5-2 mm, and the height is 2-4 mm.

9. The method for measuring a recrystallization temperature using an internal loss of a metallic material as claimed in claim 1, wherein in S1, the cold-deformed metallic material specimen is subjected to surface descaling and polishing before the test.

Technical Field

The invention relates to the technical field of nondestructive testing of metal materials, in particular to a method for measuring recrystallization temperature by utilizing internal consumption of a metal material.

Background

Due to cold deformation processing, crystal lattices of the metal or alloy material can be distorted, even crystal grains are refined, larger internal stress is generated, and work hardening is formed. The material properties and performance depend to a large extent on the microstructure, and fine-grained or nanocrystalline materials exhibit excellent properties, such as high strength and hardness. However, when deformed and fine-grained materials are exposed to high temperatures, a recrystallization process inevitably occurs in which small or deformed grains are grown into large equiaxed grains by nucleation and grain boundary migration, thereby altering the material properties. Therefore, the determination of the recrystallization temperature is of great importance for the production and use of materials.

At present, people generally adopt a metallographic method or a hardness value method to measure the recrystallization temperature of a material. The two methods are described below for simplicity and for analysis of advantages and disadvantages.

The method for determining the recrystallization temperature by adopting the metallographic method comprises the steps of carrying out isothermal annealing on a sample at different temperatures within a certain time, carrying out chemical corrosion on the annealed sample, observing the recrystallization condition of the annealed sample by using a metallographic microscope (or a scanning electron microscope), counting the volume fraction, and determining the recrystallization temperature point at the isothermal annealing time by taking the integral number of recrystallized bodies as the standard, wherein the integral number of the recrystallized bodies reaches more than 95%. Its advantage is: the recrystallization condition of the sample can be visually and clearly seen; the disadvantages are as follows: a plurality of groups of isothermal annealing tests need to be carried out, the number of samples is large, the operation steps are complicated and time-consuming, certain requirements are imposed on the chemical corrosion process in the test, and the obtained recrystallization temperature is in a temperature zone range; in addition, chemical reagents are needed in the test process, which is harmful to human bodies and can cause environmental pollution.

The recrystallization temperature is measured by a hardness method, namely, isothermal annealing is carried out on samples at different temperatures within a certain time, the samples are ground and polished by sand paper, the hardness value of each sample is measured by a hardness meter, generally, the hardness point of each sample is required to be not less than 10, then, the average value is taken as the hardness value of the sample, a curve of the hardness of the sample along with the change of the temperature under certain annealing time is obtained, and the recrystallization temperature point of the sample under the annealing time is determined by taking the hardness value of the sample reduced by 50 percent as a standard. Its advantage is: the test method is simple, green and pollution-free, and the equipment is easy to obtain. The disadvantages are as follows: a plurality of groups of isothermal annealing tests are required, the operation steps are complicated, a large number of samples are consumed, and the recrystallization temperature generally obtained is in a temperature zone range; and when the annealed sample is in a partially recrystallized state, since the tested region is divided into a deformed region and a recrystallized region, this will affect the accuracy of the test.

The internal wear test technique is very sensitive to defects in solid materials (point defects, dislocations, grain boundaries, domain boundaries, phase boundaries, and interactions between dislocations and other defects), and can be used to study the recrystallization process of metallic materials. Meanwhile, the internal consumption test process needs few samples, and only two to three small samples are needed, so that the kinetic parameters of the recrystallization process in the solid material can be conveniently, quickly and accurately obtained. Several researchers have investigated the recrystallization temperature OF metallic materials by internal consumption techniques, such as an article entitled "Investigation OF recrystallization in an Al-0.3Mg alloy by the method OF internal crystallization", PHYSICS OF METALS AND METALLOGRAPHY, 2011, 112A. The Al-0.3Mg alloy mentioned therein, which has a rolling deformation of 90%, shows a non-relaxation-type internal consumption peak, and it is confirmed that the non-relaxation-type internal consumption peak is related to the recrystallization process of the alloy and is a recrystallization internal consumption peak of the alloy. However, since the internal consumption peak of recrystallization obtained by the internal consumption test is strongly dependent on the temperature increase rate, the peak temperature of the recrystallization peak measured by the internal consumption is not the same as the classical recrystallization temperature determined during the isothermal annealing, and this problem has not been solved in the prior art.

Disclosure of Invention

Based on the technical problems in the background art, the invention provides a method for measuring the recrystallization temperature by using the internal consumption of a metal material.

The invention provides a method for measuring recrystallization temperature by using internal consumption of a metal material, which comprises the following steps:

s1, obtaining a cold deformation metal material sample, and mounting the cold deformation metal material sample on an internal friction measuring instrument;

s2, continuously heating the cold deformation metal material sample from room temperature at a constant heating rate, cooling the cold deformation metal material sample to room temperature along with a furnace, testing the internal consumption values of the cold deformation metal material sample at different frequencies, drawing temperature internal consumption curves in the heating and cooling processes at different frequencies by taking the temperature as an X axis and the internal consumption value as a Y axis, determining a recrystallization internal consumption peak, and obtaining the recrystallization internal consumption peak temperature at the constant heating rate;

s3, changing the constant heating rate, repeating the step S2 to obtain temperature internal consumption curves at different constant heating rates, and obtaining recrystallization internal consumption peak and peak temperatures at different constant heating rates;

s4, utilizing Kissinger equation to perform fitting analysis on multiple groups of constant heating rates and corresponding recrystallization internal consumption peak temperatures, and determining recrystallization kinetic parameters of the metal material;

s5, obtaining the recrystallization temperature of the traditional isothermal annealing by combining the equivalent relationship between the constant temperature rise rate of continuous temperature rise in the internal friction measuring process and the annealing time of the isothermal annealing in the measuring process of a metallographic method or a hardness method in the recrystallization process and the recrystallization kinetic parameters determined in the step S4 and by using a Kissinger equation.

Preferably, in S2, the determination of the internal consumption peak for recrystallization is determined according to the non-relaxivity characteristic of the internal consumption peak and the disappearance characteristic of the internal consumption peak during temperature reduction; the non-relaxivity of the internal consumption peak refers to the characteristic that the peak temperature of the internal consumption peak does not change along with the measurement frequency.

Preferably, the constant ramp rates in S2 and S3 are ≧ 1 deg.C/min.

Preferably, the Kissinger equation is:where θ is the constant rate of temperature rise, T_mIs the peak temperature of internal consumption peak of recrystallization, E is the equivalent activation energy, R is the ideal gas constant, C is a constant independent of theta and temperature; and in S4, performing fitting analysis on the multiple groups of constant heating rates and corresponding recrystallization internal consumption peak temperatures to determine C and E values.

Preferably, in S5, the equivalent relationship between the constant temperature-rise rate of continuous temperature rise and the annealing time of isothermal annealing is a common corresponding relationship obtained by a numerical analysis method: the isothermal annealing time is 10min, 20min, 30min and 60min respectively corresponding to constant heating rate of 0.2 ℃/min, 0.14 ℃/min, 0.064 ℃/min and 0.034 ℃/min.

Preferably, in S2, the internal friction value test adopts a forced vibration mode, and the frequency is 0.1-10 Hz.

Preferably, in S2, the shear strain amplitude of the internal friction value test is 10^-6～10^-4。

Preferably, in S1, the specifications of the cold-deformed metal material sample are: the length is 50-80 mm, the width is 0.5-2 mm, and the height is 2-4 mm.

Preferably, in S1, the cold-deformed metal material specimen is descaled and polished before testing.

In the step S1, the surface oxide skin can be removed by polishing with sandpaper, which is 60-400 mesh.

In the step S1, the polishing may be performed by sanding with sandpaper, wherein the sandpaper is 800-2000 mesh.

In the method of measuring the recrystallization temperature using the internal loss of the metal material according to the present invention, the cold-deformed metal material sample is subjected to a vacuum atmosphere for detection.

Has the advantages that: the invention provides a method for determining recrystallization temperature by utilizing internal consumption of a metal material, which is characterized in that when the internal consumption is determined by adopting continuous heating in the recrystallization process, the internal consumption peak of recrystallization strongly depends on the characteristic of heating rate, the recrystallization kinetic parameters of the metal material are obtained, and the recrystallization temperature of the traditional isothermal annealing is further determined by utilizing Kissinger equation through the equivalent relationship between the constant heating rate of continuous heating in the internal consumption determination and the annealing time of isothermal annealing in the determination process of a metallographic method or a hardness method; and the method is very close to the recrystallization temperature measured by a standard hardness method, so that the effectiveness of the method is verified, and the method has practical significance.

Because the internal consumption measuring instrument is adopted to test the internal consumption value, the internal consumption values under a plurality of frequencies can be simultaneously measured in the process of one-time temperature rise, the invention can simulate the classical isothermal recrystallization process from the continuous heating recrystallization process by simply adjusting the heating rate to obtain the recrystallization temperature of the isothermal annealing process, and the aim of measuring the recrystallization temperature of the metal material can be achieved only by two or three samples.

The invention has simple operation, easy sample preparation and simpler, faster and more reliable test. The invention belongs to the technical field of nondestructive testing of metal materials.

Drawings

FIG. 1 is a temperature-internal loss curve at different frequencies in a temperature increasing process and a temperature-internal loss curve in a temperature decreasing process at a temperature increasing rate of 2 ℃/min in example 1 of the present invention;

FIG. 2 is a graph showing temperature-internal friction curves during temperature increase at different constant temperature increase rates in example 1 of the present invention;

FIG. 3 is a linear graph of Kissinger's equation obtained by fitting in example 1 of the present invention;

FIG. 4 is a temperature-internal loss curve at different frequencies in the temperature increasing process and a temperature-internal loss curve in the temperature decreasing process at a temperature increasing rate of 2.5 ℃/min in example 2 of the present invention;

FIG. 5 is a graph showing temperature-internal friction curves during temperature increase at different constant temperature increase rates in example 2 of the present invention;

FIG. 6 is a linear graph of the Kissinger equation obtained by fitting in example 2 of the present invention.

Detailed Description

The invention provides a method for measuring recrystallization temperature by using internal consumption of a metal material, which comprises the following steps:

s1, obtaining a cold-deformation metal material sample, removing oxide skin on the surface of the cold-deformation metal material sample, polishing the cold-deformation metal material sample, and then installing the cold-deformation metal material sample on a multifunctional internal consumption measuring instrument to ensure that the cold-deformation metal material sample is in a vacuum environment. The specification of the cold-deformation metal material sample is as follows: a length of 50 to 80mm, a width of 0.5 to 2mm, and a height of 2 to 4mm (the specification in the following embodiment is selected to be 60X 2X 1 mm)³) And removing oxide skin on the surface of the metal sample by using sand paper, wherein the sand paper is 240 meshes, the polishing mode is sand paper polishing, and the sand paper is 400-2000 meshes.

S2, the multifunctional internal consumption instrument runs in a forced vibration mode, the frequency is 0.1 Hz-10 Hz, and the shear strain amplitude interval is 10^-6～10^-4From room temperature at a constant ramp rate θ₁And continuously heating, cooling to room temperature along with the furnace, and measuring the internal consumption value of the sample. Obtaining the temperature-internal consumption curve of the cold deformation metal material in the temperature rise and temperature reduction process under different frequencies by taking the temperature as an X axis and the internal consumption as a Y axis, finding out the internal consumption peak of recrystallization by checking the non-relaxation characteristic of the internal consumption peak (namely the peak temperature does not change along with the measured frequency) and the disappearance characteristic of the internal consumption peak in the temperature reduction process, and determining the constant temperature rise rate theta₁Internal consumption peak temperature T of lower recrystallization₁。

And S3, changing the constant heating rate, repeating the step S2 to obtain temperature-internal consumption curves at different constant heating rates, and determining the corresponding recrystallization internal consumption peak and peak temperatures at different constant heating rates.

And S4, carrying out fitting analysis on a plurality of groups of constant heating rates and corresponding recrystallization internal consumption peak temperatures according to a Kissinger equation, and determining the recrystallization kinetic parameters of the metal material.

S5, obtaining the recrystallization temperature of the traditional isothermal annealing by combining the equivalent relationship between the constant temperature rise rate of continuous temperature rise in the internal friction measuring process and the annealing time of the isothermal annealing in the measuring process of a metallographic method or a hardness method in the recrystallization process and the recrystallization kinetic parameters determined in the step S4 and by using a Kissinger equation.

Preferably, the temperature increase rate in steps S2 and S3 is not less than 1 ℃/min.

Preferably, the Kissinger equation is:

where θ is the rate of temperature rise, T_mIs the peak temperature of internal consumption peak of recrystallization, E is the equivalent activation energy, R is the ideal gas constant, C is a constant independent of theta and temperature;

and in S4, performing fitting analysis on the multiple groups of constant heating rates and corresponding recrystallization internal consumption peak temperatures to determine C and E values.

Preferably, in S5, the equivalent relationship between the constant temperature-rise rate of continuous temperature rise and the annealing time of isothermal annealing is a common correspondence obtained by a numerical analysis method: the isothermal annealing time is 10min, 20min, 30min and 60min respectively corresponding to constant heating rate of 0.2 ℃/min, 0.14 ℃/min, 0.064 ℃/min and 0.034 ℃/min. Wherein the isothermal annealing time of 60min is the annealing time commonly used for measuring the recrystallization temperature by a hardness method.

The technical solution of the present invention will be described in detail below with reference to specific examples.

Example 1

The material used in this example was morphotropic high purity aluminum with a purity of 99.999%.

FIG. 1 shows a constant temperature rise rate of 2 ℃/min and an amplitude of 5X 10^-5Temperature-internal consumption curve measured under the conditions. In the temperature rising process, a non-relaxation internal consumption peak P appears at 139 DEG C₁Peak, peak temperature does not shift with the measured frequency and disappears during the subsequent cooling, so that P is determined₁The peak is the internal consumption peak of recrystallization of high-purity aluminum. And P is₂Peaks appear during the ramping and cooling process and move with frequency, so P₂The peak is the internal loss peak of the grain boundary.

FIG. 2 shows the temperature at constant heating rates of 1, 1.5, 2, 3, 4, 5 deg.C/min, and amplitude of 5X 10^-5Under the condition of the measured temperature-internal consumption curve, it can be seen that the internal consumption peak position moves to high temperature along with the increase of the temperature rising rate. Determining the peak temperature of the internal consumption peak of recrystallization corresponding to different constant temperature rise rates from the curve.

FIG. 3 is a Kissinger equation diagram, i.e., ln (θ/T)²) 1/T curve. And (3) performing Kissinger equation fitting analysis on the corresponding recrystallization internal consumption peak temperature data under different constant temperature rise rates in the graph 2 to determine that the recrystallization kinetic parameters of the cold deformation high-purity aluminum are respectively as follows: e-56.59 kJ/mol, C-5.13.

Table 1 shows the recrystallization temperatures calculated from the change in hardness and the Kissinger equation, which are respectively designated as hardness-T_△HV/2And Kissinger equation-T_△HV/2As can be seen from table 1, the recrystallization temperature calculated using the Kissinger equation is very close to the recrystallization temperature measured by the standard hardness method.

TABLE 1

Example 2

The material used in this example was morphotropic high purity copper with a purity of 99.99%.

FIG. 4 shows a constant temperature rise rate of 2.5 ℃/min and a strain amplitude of 5X 10^-5Temperature-internal consumption curve measured under the conditions. In the temperature rising process, a non-relaxation internal consumption peak P appears at 331.5 DEG C₁Peak, peak temperature does not shift with the measured frequency, disappears during subsequent cooling, so P is determined₁The peak is the internal consumption peak of recrystallization of high-purity copper. The peak P2 appears during the heating and cooling process and moves with the frequency, so P₂The peak is the internal loss peak of the grain boundary. Here, a lower measurement frequency (0.4-0.6Hz) is used, mainly to shift the internal loss peak of the grain boundary to a lower temperature, away from the internal loss peak of recrystallization at a higher temperature.

FIG. 5 shows the amplitude of 5X 10 at constant heating rates of 1, 2, 2.5, 3, 4, and 5 deg.C/min^-5Under the condition of the measured temperature-internal consumption curve, it can be seen that the internal consumption peak position moves to high temperature along with the increase of the temperature rising rate. Determining from the internal friction curve for different heating ratesInternal consumption peak temperature of recrystallization.

FIG. 6 is a Kissinger equation diagram, i.e., ln (θ/T)²) 1/T curve. And (3) performing Kissinger equation fitting analysis on the corresponding recrystallization internal consumption peak temperature data under different constant temperature rise rates in the graph 5 to determine that the recrystallization kinetic parameters of the cold deformation high-purity copper are respectively as follows: e is 143.31kJ/mol, C is 16.63.

Table 2 shows the recrystallization temperatures calculated from the change in hardness and the Kissinger equation, which are respectively designated as hardness-T_△HV/2And Kissinger equation-T_△HV/2As can be seen from table 2, the recrystallization temperature calculated using the Kissinger equation is very close to the recrystallization temperature measured by the standard hardness method.

TABLE 2

The scheme of the application is proved to be effective in testing the recrystallization temperature of the metal material by comparing with the hardness method experiment. By adopting the detection method, the recrystallization temperature of the traditional isothermal annealing process can be obtained by the internal consumption test of continuous temperature rise and the Kissinger equation, and the aim of measuring the recrystallization temperature of the metal material can be achieved by only two or three samples.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.