Test method for obtaining relationship between hydrogen concentration and hydrogen embrittlement risk of metal material

Abstract

The invention discloses a test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metal material. The test method comprises the following steps: S1, preparing a sample; s2, performing hydrogen desorption on the sample by utilizing a thermal desorption method to obtain the diffusible hydrogen content in the sample; s3, preparing a hydrogen charging solution, and performing different-time-length hydrogen charging on the sample by utilizing electrochemical hydrogen charging to obtain a hydrogen charging sample; s4, measuring hydrogen of the hydrogen-filled samples one by one according to the hydrogen-filled duration to obtain saturated hydrogen concentration of the samples, and establishing a hydrogen concentration change curve; s5, preparing a slow tensile sample, and charging hydrogen into the slow tensile sample according to the hydrogen concentration change curve; s6, performing a slow tensile test on the slow tensile sample; s7, acquiring a hydrogen embrittlement risk index of the sample according to a result of the slow tensile test; and S8, establishing a hydrogen concentration and hydrogen embrittlement risk curve. The method can directly associate the hydrogen concentration of the metal material with the hydrogen embrittlement risk and quantify the relationship between the hydrogen concentration and the hydrogen embrittlement risk, and has guiding significance on hydrogen embrittlement risk evaluation of the metal material in the actual production and use process.

Description

Technical Field

[0001] This invention relates to the field of hydrogen embrittlement, and more specifically, to a test method for obtaining the relationship between hydrogen concentration and hydrogen embrittlement risk in metallic materials. Background Technology

[0002] Hydrogen embrittlement is a form of environmental failure in metallic materials. It exhibits several significant characteristics: (1) it deteriorates mechanical properties, particularly significantly reducing elongation and reduction of area; (2) it alters the fracture mechanism, resulting in different fracture morphologies, primarily manifested as a shift in fracture mode from ductile dimple fracture to brittle cleavage or intergranular fracture as the hydrogen concentration in the material increases; and (3) the fracture occurs suddenly without obvious warning signs, often leading to serious consequences. However, hydrogen is inevitably introduced into steel materials during smelting, pickling, electroplating, welding, and subsequent processing and use by users.

[0003] Hydrogen exists in steel in two states: non-diffusible hydrogen and diffusible hydrogen. Diffusible hydrogen can diffuse within steel and accumulate in defects and grain boundaries. The interaction between diffusible hydrogen and stress is the main cause of hydrogen embrittlement and delayed fracture in ultra-high strength steel. Therefore, the concentration of diffusible hydrogen is directly related to the hydrogen embrittlement risk of high-strength steel. Currently, there is relatively little research on hydrogen concentration levels in ultra-high strength steel by scholars both domestically and internationally. Relevant literature is scarce. Most studies involve hydrogen charging of samples at a certain current density followed by hydrogen embrittlement and delayed cracking risk assessment tests. These tests primarily evaluate hydrogen embrittlement by linking the charging current and time with the sample's plasticity loss, using a method that substitutes charging current and time for hydrogen concentration—an indirect method that cannot directly reveal the relationship between hydrogen concentration and the hydrogen embrittlement risk of metallic materials. Summary of the Invention

[0004] In view of the deficiencies in the existing technology, the purpose of this invention is to provide an experimental method for obtaining the relationship between hydrogen concentration and hydrogen embrittlement risk of metallic materials. This method can directly link the hydrogen concentration of metallic materials with the risk of hydrogen embrittlement and quantify the relationship between the two, which has guiding significance for the assessment of hydrogen embrittlement risk of metallic materials in actual production and use.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] This invention provides an experimental method for obtaining the relationship between hydrogen concentration and hydrogen embrittlement risk in metallic materials, comprising the following steps:

[0007] S1, Sample preparation;

[0008] S2, using thermal desorption to release hydrogen from the sample and obtain the diffusible hydrogen content in the sample;

[0009] S3, prepare hydrogen charging solution, and use electrochemical hydrogen charging to charge the sample for different durations to obtain hydrogen-charged samples;

[0010] S4. Measure the hydrogen concentration of each hydrogen-filled sample according to the hydrogen filling time to obtain the saturated hydrogen concentration of the sample and establish a hydrogen concentration change curve.

[0011] S5, prepare a slow stretching sample, and fill the slow stretching sample with hydrogen according to the hydrogen concentration change curve;

[0012] S6, Perform a slow tensile test on the slow tensile sample;

[0013] S7. Obtain the hydrogen embrittlement risk index of the sample based on the results of the slow tensile test.

[0014] S8, establish hydrogen concentration and hydrogen embrittlement risk curve.

[0015] Preferably, in step S1, the sample is prepared by shearing and the sample surface is treated by acetone ultrasonication.

[0016] Preferably, in step S2, a German Bruker hydrogen analyzer is used to heat the sample at 400°C for 20 min to 1 h using thermal desorption to obtain the diffusible hydrogen content of the sample.

[0017] Preferably, in step S3, the hydrogen charging solution is a 0.5 mol / L H2SO4 + 0.3 g / L thiourea solution.

[0018] Preferably, in step S3, the electrochemical hydrogen charging is performed using an electrochemical constant current mode with a current of 10 mA / cm². 2 The surface-treated samples were placed in a hydrogen charging solution for different durations of hydrogen charging, ranging from 10 min to 10 h. The hydrogen-charged samples were then stored in liquid nitrogen.

[0019] Preferably, in step S4, the saturated hydrogen concentration is the hydrogen concentration corresponding to the point when the difference between hydrogen contents is less than 0.1 ppm during the process of measuring hydrogen one by one.

[0020] Preferably, in step S5, when purging the slowly stretched sample with hydrogen, the hydrogen concentration ranges between the diffusible hydrogen content in the sample and the saturated hydrogen concentration in the sample.

[0021] Preferably, in step S6, the slow tensile test is as follows:

[0022] The slow-stretching sample was subjected to a slow-stretching test immediately after hydrogen purging, with a slow-stretching speed of (5-T). S / 1000)*10 -4 mm / s, T STo determine the tensile strength of the sample, a slow tensile test was conducted on the unhydrogenated slow tensile sample at the same slow tensile speed to obtain the slow tensile curve.

[0023] Preferably, in step S7, the hydrogen embrittlement risk index of the sample is I = 1 - S / Su, where I is the hydrogen embrittlement risk index of the sample, S is the elongation of the slowly stretched sample after hydrogen charging, and Su is the elongation of the slowly stretched sample without hydrogen charging.

[0024] Preferably, in step S8, the hydrogen concentration and hydrogen embrittlement risk curve is plotted based on the hydrogen concentration obtained in step S5 and the hydrogen embrittlement index obtained in step S7.

[0025] The beneficial effects of this invention are:

[0026] This invention utilizes an electrochemical hydrogen charging method combined with diffuse hydrogen measurement to obtain the relationship between hydrogen concentration and charging time. Using this relationship curve, the diffuse hydrogen concentration inside high-strength steel after different charging times can be determined. Subsequently, by combining this with a slow tensile test, the relationship between hydrogen concentration and elongation can be obtained by comparing the changes in fracture elongation of samples with different hydrogen concentrations and those without hydrogen charging. This leads to the correlation between hydrogen concentration and hydrogen embrittlement risk. This invention can quantitatively and intuitively represent the relationship between hydrogen concentration and hydrogen embrittlement risk, making hydrogen embrittlement risk assessment more intuitive. Using the method provided by this invention, curves can be plotted to obtain the hydrogen embrittlement risk of samples under different hydrogen concentrations, enabling hydrogen embrittlement risk assessment for samples under different conditions. Attached Figure Description

[0027] Figure 1 This is a schematic flowchart of the experimental method for obtaining the relationship between hydrogen concentration and hydrogen embrittlement risk of metallic materials according to the present invention.

[0028] Figure 2 This is a schematic diagram of the slow-stretch sample of the present invention;

[0029] Figure 3 This is the curve showing the relationship between DP1180 diffusing hydrogen concentration and hydrogen embrittlement risk in Example 1 of this invention;

[0030] Figure 4 This is the curve showing the relationship between the MS1300 diffusing hydrogen concentration and hydrogen embrittlement risk in Example 2 of this invention;

[0031] Figure 5 This is the curve showing the relationship between the diffusing hydrogen concentration and hydrogen embrittlement risk of QP1180 in Example 3 of this invention. Detailed Implementation

[0032] To better understand the above-mentioned technical solutions of the present invention, the technical solutions of the present invention will be further described below in conjunction with the accompanying drawings and embodiments.

[0033] Combination Figure 1As shown, the present invention provides a test method for obtaining the relationship between hydrogen concentration and hydrogen embrittlement risk in metallic materials, comprising the following steps:

[0034] S1, Sample preparation;

[0035] The metal material was cut into 100mm x 20mm sheets using a shearing method, ensuring the sample surface was flat and free of bends. Thirty sheets of each type were prepared. The samples were then subjected to acetone ultrasonic treatment for approximately 15 minutes to ensure a clean surface.

[0036] S2, using thermal desorption to release hydrogen from the sample and obtain the diffusible hydrogen content in the sample;

[0037] The hydrogen content of the sample was obtained by heating the sample at 400℃ for 20 min to 1 h using a German Bruker hydrogen analyzer and thermal desorption.

[0038] S3, prepare hydrogen charging solution, and use electrochemical hydrogen charging to charge the sample for different durations to obtain hydrogen-charged samples;

[0039] A 0.5 mol / L H₂SO₄ + 0.3 g / L thiourea solution was prepared as the hydrogen charging solution and stored at room temperature for 24 hours before use. An electrochemical galvanostatic mode was used with a current constant of 10 mA / cm². 2 The surface-treated samples were placed in a hydrogen charging solution for different durations of hydrogen charging, ranging from 10 min to 10 h. The hydrogen-charged samples were then stored in liquid nitrogen.

[0040] S4. Measure the hydrogen concentration of each hydrogen-filled sample according to the hydrogen filling time to obtain the saturated hydrogen concentration of the sample and establish a hydrogen concentration change curve.

[0041] After the hydrogen-charged samples are thawed, the hydrogen content of each sample is measured according to the hydrogen charging time until the difference between the hydrogen contents is less than 0.1 ppm. The hydrogen content at this point is the saturated hydrogen concentration Cm of the sample. At the same time, the relationship between hydrogen charging concentration and time is recorded to establish a hydrogen concentration change curve.

[0042] S5, prepare a slow stretching sample, and fill the slow stretching sample with hydrogen according to the hydrogen concentration change curve;

[0043] The sample was prepared according to Figure 2 The slow-stretch sample was fabricated from the drawing shown. The fabricated slow-stretch sample was ultrasonicated with acetone for 15 minutes to ensure the sample surface was clean. Then, silicone was used to coat the rest of the sample except for the gauge length. The sample was then left to stand for 5 hours to ensure that the silicone on the sample surface solidified and dried. The gauge length is the original length of the sample part used to measure the strain or length change of the sample.

[0044] Based on the changing pattern of hydrogen concentration, the slow-stretched sample was quantitatively charged with hydrogen. When charging the slow-stretched sample with hydrogen, the hydrogen concentration ranged between the diffusible hydrogen content in the sample and the saturated hydrogen concentration of the sample.

[0045] S6, Perform a slow tensile test on the slow tensile sample;

[0046] The slow tensile test was performed immediately after the hydrogen purging of the sample. The sample was mounted on the slow tensile testing machine, and the slow tensile speed was (5-T). S / 1000)*10 -4 mm / s, T S To determine the tensile strength of the sample, a slow tensile test was conducted on the unhydrogenated slow tensile sample at the same slow tensile speed to obtain the slow tensile curve.

[0047] S7. Obtain the hydrogen embrittlement risk index of the sample based on the results of the slow tensile test.

[0048] The hydrogen embrittlement risk index of the sample is I = 1 - S / Su, where I is the hydrogen embrittlement risk index of the sample, S is the elongation of the slowly stretched sample after hydrogen charging, and Su is the elongation of the slowly stretched sample without hydrogen charging.

[0049] S8, establish hydrogen concentration and hydrogen embrittlement risk curve.

[0050] Based on the hydrogen concentration obtained in step S5 and the hydrogen embrittlement index obtained in step S7, a hydrogen concentration versus hydrogen embrittlement risk curve is plotted.

[0051] The principle of this invention lies in the fact that diffusible hydrogen is a key factor leading to hydrogen embrittlement risk in high-strength steel. Under given high-strength steel and stress conditions, hydrogen concentration is directly related to hydrogen embrittlement. Furthermore, for a given high-strength steel, the relationship between hydrogen concentration and hydrogen charging time can be obtained through electrochemical hydrogen charging combined with diffusible hydrogen measurement. Using this relationship curve, the internal diffusible hydrogen concentration of the high-strength steel after different hydrogen charging times can be obtained. After obtaining the diffusible hydrogen concentration, combined with a slow tensile test, the relationship between hydrogen concentration and elongation can be obtained by comparing the changes in fracture elongation of samples with different hydrogen concentrations and those without hydrogen charging. Thus, the correlation between hydrogen concentration and hydrogen embrittlement risk is derived.

[0052] Example 1

[0053] In this embodiment, DP1180 cold-rolled finished sheet was selected from the production site as the test material. The specific steps are as follows:

[0054] (1) Sample preparation: The samples were cut to 100mm*20mm size by shearing to ensure that the sample surface was flat and without bending. 30 pieces of each type of sample were prepared.

[0055] (2) Sample surface treatment: The sample was ultrasonicated with acetone for 15 minutes to ensure that the sample surface was clean.

[0056] (3) Hydrogen determination method: The sample was heated at 400℃ for 20 min to 1 h using a German Bruker hydrogen analyzer and the hydrogen was released by thermal desorption to obtain the diffusible hydrogen content.

[0057] (4) Prepare hydrogen charging solution: Prepare a 0.5 mol / L H2SO4 + 0.3 g / L thiourea solution as hydrogen charging solution and store it at room temperature for 24 hours before use;

[0058] (5) Electrochemical hydrogen charging: using an electrochemical constant current mode with 10 mA / cm² 2 The surface-treated samples were placed in a hydrogen charging solution for different durations of hydrogen charging, ranging from 10 min to 10 h, using varying hydrogen charging currents.

[0059] (6) Sample preservation: After hydrogen purging, the sample is placed in liquid nitrogen for preservation and later use;

[0060] (7) Plotting hydrogen concentration change curve: After the sample is thawed, the hydrogen content of each hydrogen-filled sample is measured according to the hydrogen filling time until the difference between the hydrogen contents is less than 0.1 ppm. The saturated hydrogen concentration of the sample is 3.1 ppm. At the same time, the relationship between hydrogen filling concentration and time is recorded to establish a hydrogen concentration change curve.

[0061] (8) Slow-stretch sample preparation: Prepare the sample according to... Figure 2 The sample was processed according to the drawing shown. After processing, the sample was ultrasonically sonicated with acetone for 15 minutes to ensure that the sample surface was clean. Then, silicone was used to coat all parts except the gauge length. The sample was then left to stand for 5 hours to ensure that the silicone on the sample surface solidified and dried.

[0062] (9) Hydrogen charging of slow stretching samples: Based on the hydrogen concentration change curve, the slow stretching samples are quantitatively charged with hydrogen to obtain the sample with the required hydrogen concentration; the range of hydrogen charging concentration is between the diffusible hydrogen content in the sample and the saturated hydrogen concentration of the sample.

[0063] (10) Slow tensile test: After hydrogen purging, the sample is immediately mounted on the slow tensile testing machine, and the slow tensile speed is 3.8*10. -4 mm / s (tensile strength T of the sample) S The pressure was 1180 MPa), and then the stretching began immediately. The same slow stretching speed was used for the uncharged sample to obtain the slow stretching curves of the two samples.

[0064] (11) Hydrogen embrittlement risk index: The hydrogen embrittlement risk index I = 1 - S / Su, where I is the hydrogen embrittlement risk index of the sample, S is the elongation of the hydrogen-filled slow-stretched sample, and Su is the elongation of the unfilled slow-stretched sample. The results are shown in Table 1.

[0065] Table 1. Parameters related to hydrogen embrittlement risk assessment of DP1180

[0066]

[0067] (12) Plot the curves corresponding to hydrogen concentration and hydrogen embrittlement risk: Based on the relevant parameters in Table 1, obtain the curves of hydrogen concentration and hydrogen embrittlement risk as follows: Figure 2 As shown.

[0068] Example 2

[0069] In this embodiment, MS1300 cold-rolled finished sheet was selected from the production site as the test material. The specific steps are as follows:

[0070] (1) Sample preparation: The samples were cut to 100mm*20mm size by shearing to ensure that the sample surface was flat and without bending. 30 pieces of each type of sample were prepared.

[0071] (2) Sample surface treatment: The sample was ultrasonicated with acetone for 15 minutes to ensure that the sample surface was clean.

[0072] (3) Hydrogen determination method: The sample was heated at 400℃ for 20 min to 1 h using a German Bruker hydrogen analyzer and the hydrogen was released by thermal desorption to obtain the diffusible hydrogen content.

[0073] (4) Prepare hydrogen charging solution: Prepare a 0.5 mol / L H2SO4 + 0.3 g / L thiourea solution as hydrogen charging solution and store it at room temperature for 24 hours before use;

[0074] (5) Electrochemical hydrogen charging: using an electrochemical constant current mode with 10 mA / cm² 2 The surface-treated samples were placed in a hydrogen charging solution for different durations of hydrogen charging, ranging from 10 min to 10 h, using varying hydrogen charging currents.

[0075] (6) Sample preservation: After hydrogen purging, the sample is placed in liquid nitrogen for preservation and later use;

[0076] (7) Plotting hydrogen concentration change curve: After the sample is thawed, the hydrogen content of each hydrogen-filled sample is measured according to the hydrogen filling time until the difference between the hydrogen contents is less than 0.1 ppm. The saturated hydrogen concentration of the sample is 1.1 ppm. At the same time, the relationship between hydrogen filling concentration and time is recorded to establish a hydrogen concentration change curve.

[0077] (8) Slow-stretch sample preparation: Prepare the sample according to... Figure 2 The sample was processed according to the drawing shown. After processing, the sample was ultrasonically sonicated with acetone for 15 minutes to ensure that the sample surface was clean. Then, silicone was used to coat all parts except the gauge length. The sample was then left to stand for 5 hours to ensure that the silicone on the sample surface solidified and dried.

[0078] (9) Hydrogen charging of slow stretching samples: Based on the hydrogen concentration change curve, the slow stretching samples are quantitatively charged with hydrogen to obtain the required hydrogen concentration; the range of hydrogen charging concentration is between the diffusible hydrogen content in the sample and the saturated hydrogen concentration of the sample.

[0079] (10) Slow tensile test: After hydrogen purging, the sample is immediately mounted on the slow tensile testing machine, and the slow tensile speed is 3.7*10. -4 mm / s (tensile strength T of the sample) S (1300MPa), and then immediately began stretching. The same slow stretching speed was used for the uncharged sample to obtain the slow stretching curves of the two samples.

[0080] (11) Hydrogen embrittlement risk index: The hydrogen embrittlement risk index I = 1 - S / Su, where I is the hydrogen embrittlement risk index of the sample, S is the elongation of the hydrogen-filled slow-stretched sample, and Su is the elongation of the unfilled slow-stretched sample. The results are shown in Table 2.

[0081] Table 2. Parameters related to MS1300 hydrogen embrittlement risk assessment

[0082]

[0083] (12) Plot the curves corresponding to hydrogen concentration and hydrogen embrittlement risk: Based on the relevant parameters in Table 2, obtain the curves of hydrogen concentration and hydrogen embrittlement risk as follows: Figure 4 As shown.

[0084] Example 3

[0085] In this embodiment, QP1180 cold-rolled finished steel sheets were selected from the production site as the test material. The specific steps are as follows:

[0086] (1) Sample preparation: The samples were cut to 100mm*20mm size by shearing to ensure that the sample surface was flat and without bending. 30 pieces of each type of sample were prepared.

[0087] (2) Sample surface treatment: The sample was ultrasonicated with acetone for 15 minutes to ensure that the sample surface was clean.

[0088] (3) Hydrogen determination method: The sample was heated at 400℃ for 20 min to 1 h using a German Bruker hydrogen analyzer and the hydrogen was released by thermal desorption to obtain the diffusible hydrogen content.

[0089] (4) Prepare hydrogen charging solution: Prepare a 0.5 mol / L H2SO4 + 0.3 g / L thiourea solution as hydrogen charging solution and store it at room temperature for 24 hours before use;

[0090] (5) Electrochemical hydrogen charging: using an electrochemical constant current mode with 10 mA / cm² 2The surface-treated samples were placed in a hydrogen charging solution for different durations of hydrogen charging, ranging from 10 min to 10 h, using varying hydrogen charging currents.

[0091] (6) Sample preservation: After hydrogen purging, the sample is placed in liquid nitrogen for preservation and later use;

[0092] (7) Plotting the hydrogen concentration change curve: After the sample is thawed, the hydrogen content of each hydrogen-filled sample is measured according to the hydrogen filling time until the difference between the hydrogen contents is less than 0.1 ppm. The saturated hydrogen concentration of the sample is 3.52 ppm. At the same time, the relationship between hydrogen filling concentration and time is recorded to establish the hydrogen concentration change curve.

[0093] (8) Slow-stretch sample preparation: Prepare the sample according to... Figure 2 The sample was processed according to the drawing shown. After processing, the sample was ultrasonically sonicated with acetone for 15 minutes to ensure that the sample surface was clean. Then, silicone was used to coat all parts except the gauge length. The sample was then left to stand for 5 hours to ensure that the silicone on the sample surface solidified and dried.

[0094] (9) Hydrogen purging of slow-stretched samples: Based on the hydrogen concentration change curve, the slow-stretched samples are quantitatively purged with hydrogen to obtain the sample with the required hydrogen concentration.

[0095] (10) Slow tensile test: After hydrogen purging, the sample is immediately mounted on the slow tensile testing machine, and the slow tensile speed is 3.9*10. -4 mm / s (tensile strength T of the sample) S The pressure was 1180 MPa), and then the stretching began immediately. The same slow stretching speed was used for the uncharged sample to obtain the slow stretching curves of the two samples.

[0096] (11) Hydrogen embrittlement risk index: The hydrogen embrittlement risk index I = 1 - S / Su, where I is the hydrogen embrittlement risk index of the sample, S is the elongation of the hydrogen-filled slow-stretched sample, and Su is the elongation of the unfilled slow-stretched sample. The results are shown in Table 3.

[0097] Table 3. Relevant parameters for QP1180 hydrogen embrittlement risk assessment

[0098]

[0099] (12) Plot the curves corresponding to hydrogen concentration and hydrogen embrittlement risk: Based on the relevant parameters in Table 3, obtain the curves of hydrogen concentration and hydrogen embrittlement risk as follows: Figure 5 As shown.

[0100] As shown in Examples 1-3, the experimental method of the present invention for obtaining the relationship between hydrogen concentration and hydrogen embrittlement risk of metallic materials can express the relationship between hydrogen concentration and hydrogen embrittlement risk in a quantitative and intuitive way, making the evaluation of hydrogen embrittlement risk more intuitive. By using the method provided by the present invention to draw curves, the hydrogen embrittlement risk of samples under hydrogen concentration can be obtained, and the hydrogen embrittlement risk of samples under different conditions can be evaluated.

[0101] Those skilled in the art should recognize that the above embodiments are merely illustrative of the present invention and are not intended to limit the present invention. Any variations or modifications to the above embodiments that are within the spirit and essence of the present invention will fall within the scope of the claims of the present invention.

Claims

1. A test method for obtaining a relationship between hydrogen concentration and hydrogen embrittlement risk of a metal material, characterized by, The method comprises the following steps: S1, sample preparation; S2, hydrogen desorption of the sample is performed by using a thermal desorption method to obtain the diffusion hydrogen content in the sample; S3, a hydrogen charging solution is configured, and the sample is charged with hydrogen for different lengths of time to obtain hydrogen-charged samples; S4, hydrogen in the hydrogen-charged samples is measured according to the hydrogen charging time to obtain the saturated hydrogen concentration of the sample and establish a hydrogen concentration change curve; S5, a slow tensile sample is prepared, and the slow tensile sample is charged with hydrogen according to the hydrogen concentration change curve; S6, the slow tensile sample is subjected to a slow tensile test; S7, a hydrogen embrittlement risk index of the sample is obtained according to the result of the slow tensile test; S8, a hydrogen concentration-hydrogen embrittlement risk curve is established.

2. The test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metallic material according to claim 1, characterized in that: In the step S1, the sample is prepared in a shearing manner, and the sample surface is treated by using an acetone ultrasonic method.

3. The test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metallic material according to claim 1, characterized in that: In the step S2, the sample is heated at 400 DEG C for 20 min to 1 h by using a thermal desorption method to obtain the diffusion hydrogen content in the sample by using a German Bruker hydrogen analyzer.

4. The test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metallic material according to claim 1, characterized in that, In the step S3, the hydrogen charging solution is a 0.5 mol / L H2SO4+0.3 g / L thiourea solution.

5. The test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metallic material according to claim 1, characterized in that: In the step S3, the electrochemical hydrogen charging is performed by using an electrochemical constant current mode with a hydrogen charging current of 10 mA / cm 2 for different lengths of time, the hydrogen charging time being 10 min to 10 h, and the hydrogen charged sample is stored in liquid nitrogen.

6. The test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metallic material according to claim 1, characterized in that, In the step S4, the saturated hydrogen concentration is the hydrogen concentration corresponding to the case where the difference between hydrogen contents is less than 0.1 ppm in the process of measuring hydrogen one by one.

7. The test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metallic material according to claim 1, characterized in that: In the step S5, when the slow tensile sample is charged with hydrogen, the hydrogen charging concentration ranges between the diffusion hydrogen content in the sample and the saturated hydrogen concentration of the sample.

8. The test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metallic material according to claim 1, characterized in that, In the step S6, the slow tensile test is as follows: The slow stretch sample was immediately subjected to slow stretch test after the hydrogen charging was completed, and the slow stretch speed was (5-T S / 1000)*10 -4 mm / s, T S was the tensile strength of the sample. The slow stretch test was performed on the slow stretch sample without hydrogen charging at the same slow stretch speed, and the slow stretch curve was obtained.

9. The test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metallic material according to claim 8, characterized in that, In the step S7, the hydrogen embrittlement risk index I of the sample is I=1-S / Su, I is the hydrogen embrittlement risk index of the sample, S is the elongation of the slow tensile sample after hydrogen charging, and Su is the elongation of the slow tensile sample without hydrogen charging.

10. The test method for obtaining the relationship between the hydrogen concentration and the hydrogen embrittlement risk of a metallic material according to claim 1, characterized in that, In the step S8, the hydrogen concentration-hydrogen embrittlement risk curve is drawn according to the hydrogen concentration of step S5 and the hydrogen embrittlement index obtained in step S7.

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