Treatment process method for improving strength and plasticity of hydrogen isolation diaphragm and hydrogen isolation diaphragm

Abstract

The invention discloses a treatment process method for improving the strength and plasticity of a hydrogen isolation diaphragm and the hydrogen isolation diaphragm. The treatment process method comprises the following steps: S1, carrying out high-frequency vibration and static pressure coupling treatment on the hydrogen isolation diaphragm; and S2, the hydrogen isolation diaphragm is subjected to snakelike line rolling treatment. The hydrogen isolation diaphragm is treated by the treatment process method. According to the treatment process method, high-frequency vibration and static pressure coupling treatment is carried out on the hydrogen isolation diaphragm, and a gradient nanostructure and residual compressive stress are introduced into the surface layer of the hydrogen isolation diaphragm, so that the strength and plasticity of the hydrogen isolation diaphragm are remarkably improved, and the hydrogen embrittlement sensitivity is reduced; therefore, the service life of the hydrogen isolation diaphragm in the high-pressure hydrogen diaphragm compressor is prolonged, and the safety and reliability of equipment are improved.

Description

Technical Field

[0001] The present invention relates to a metal material processing technology, in particular to a processing method for improving the strength and plasticity of a hydrogen isolation diaphragm and a hydrogen isolation diaphragm. Background Art

[0002] Hydrogen energy, with its energy density of 33.26 kWh / kg per unit mass (three times that of traditional fuels), coupled with its zero-carbon nature, producing only water upon combustion, demonstrates potential as a replacement for other sectors, including transportation, industry, and electricity. Diaphragm compressors, the core equipment of high-pressure gaseous hydrogen storage systems, utilize their core metal diaphragms, often made of the highly elastic 00Cr15Ni5 alloy material that complies with the GB / T 14992 standard. This alloy combines high tensile strength and elongation, maintaining excellent fatigue resistance even under high loads.

[0003] However, when exposed to hydrogen in high-voltage, high-frequency environments, 00Cr15Ni5 alloy is susceptible to hydrogen embrittlement, which degrades the alloy's mechanical properties, shortens its lifespan, and ultimately leads to alloy failure, which in turn can cause gas or oil leaks and create safety concerns.

[0004] In summary, the problems to be solved by the present invention are:

[0005] In existing hydrogen diaphragm compressors, the isolation diaphragm made of martensitic stainless steel is exposed to a hydrogen environment for a long time, which makes it prone to hydrogen embrittlement, further leading to reduced mechanical properties and shortened service life. Summary of the Invention

[0006] The purpose of the present invention is to provide a treatment process method and a hydrogen isolation diaphragm for improving the strength and plasticity of a hydrogen isolation diaphragm. After being treated by the treatment process method of the present invention, the strength and plasticity of the hydrogen isolation diaphragm are significantly improved, thereby reducing the sensitivity to hydrogen embrittlement.

[0007] In order to achieve the above technical objectives, the present invention adopts the following technical solutions:

[0008] A processing method for improving the strength and plasticity of a hydrogen isolation diaphragm, the processing method comprising: S1, performing high-frequency vibration and static pressure coupling processing on the hydrogen isolation diaphragm; S2, performing serpentine line rolling processing on the hydrogen isolation diaphragm.

[0009] Furthermore, in step S1, the parameters of the high-frequency vibration applied are: the vibration frequency is 10~15KHz; in step S1, the parameters of the static pressure applied are: the downward pressure is 0.1~0.5mm, the feed speed is 1000~1500mm / min, and the step distance is 0.05~0.1mm; in step S2, the number of serpentine line rolling treatments on the hydrogen isolation diaphragm is 1 to 3 times.

[0010] Furthermore, in step S1, the parameters selected for the high-frequency vibration applied are: the vibration frequency is 14KHz; in step S1, the parameters selected for the static pressure applied are: the downward pressure is 0.1mm, the feed speed is 1200mm / min, and the step distance is 0.06mm; in step S2, the number of serpentine line rolling treatments on the hydrogen isolation diaphragm is 1 time.

[0011] Furthermore, in step S1, the parameters of the high-frequency vibration applied are: the vibration frequency is 15KHz; in step S1, the parameters of the static pressure applied are: the downward pressure is 0.5mm, the feed speed is 1000mm / min, and the step distance is 0.05mm; in step S2, the serpentine line rolling treatment is performed on the hydrogen isolation diaphragm three times.

[0012] Furthermore, in step S1, the parameters of the high-frequency vibration applied are: the vibration frequency is 13KHz; in step S1, the parameters of the static pressure applied are: the downward pressure is 0.3mm, the feed speed is 1100mm / min, and the step distance is 0.07mm; in step S2, the serpentine line rolling treatment is performed on the hydrogen isolation diaphragm twice.

[0013] A hydrogen isolation diaphragm is processed by the above-mentioned processing method.

[0014] Compared with the prior art, the treatment process method for improving the strength and plasticity of the hydrogen isolation diaphragm and the hydrogen isolation diaphragm of the present invention have the following beneficial effects:

[0015] The treatment process method of the present invention performs high-frequency vibration and static pressure coupling treatment on the hydrogen isolation diaphragm, introduces gradient nanostructure and residual compressive stress on the surface of the hydrogen isolation diaphragm, thereby significantly improving the strength and plasticity of the hydrogen isolation diaphragm, reducing the sensitivity to hydrogen embrittlement, and thereby extending the service life of the hydrogen isolation diaphragm in the high-pressure hydrogen diaphragm compressor, and improving the safety and reliability of the equipment. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of the yield strength, tensile strength and elongation of a hydrogen isolation diaphragm made of martensitic stainless steel before and after treatment, according to the treatment process for improving the strength and plasticity of the hydrogen isolation diaphragm of the present invention;

[0017] Figure 2 These are the grain structure diagrams of the hydrogen isolation diaphragm made of martensitic stainless steel before and after treatment involved in the treatment process method of the present invention, wherein small figure a is conventional treatment and small figure b is ultrasonic rolling treatment. DETAILED DESCRIPTION

[0018] The treatment process of the present invention is implemented on an elastic isolation diaphragm of a hydrogen diaphragm compressor, which is referred to as a "hydrogen isolation diaphragm" for convenience.

[0019] Those skilled in the art will understand that this hydrogen isolation diaphragm, installed in a hydrogen diaphragm compressor, primarily isolates hydrogen under high pressure to prevent leakage, while also withstanding periodic pressure fluctuations to ensure the proper operation and safety of the compressor. It should possess excellent elasticity, strength, and fatigue resistance to improve the compressor's operating efficiency and service life, reduce the risk of hydrogen embrittlement, and ensure the reliability and stability of the hydrogen compression process.

[0020] The overall concept of the treatment process of the present invention is as follows:

[0021] High-frequency vibration and static pressure are applied to the hydrogen isolation diaphragm at the same time. Under the coupling effect of high-frequency vibration and static pressure, gradient nanostructure and residual compressive stress are introduced on the surface of the hydrogen isolation diaphragm. In this way, the diffusion of hydrogen elements into the hydrogen isolation diaphragm material can be inhibited, thereby effectively reducing the hydrogen embrittlement sensitivity of the hydrogen isolation diaphragm and further improving the strength and plasticity of the hydrogen isolation diaphragm.

[0022] Specifically speaking of technology,

[0023] The process uses a 0.1-0.5mm press depth, a feed rate of 1000-1500mm / min, a vibration frequency of 10-15kHz, and a step size of 0.05-0.1mm. The rolling process is performed in a serpentine pattern, or by first rolling horizontally and then vertically, with one to three passes. The high-frequency vibration and static pressure induce intense plastic deformation and work hardening on the surface of the hydrogen isolation diaphragm. This treatment reduces surface roughness, forms a plastic deformation layer, and generates residual compressive stress, significantly improving surface quality.

[0024] The specific embodiments of the present invention are further described below:

[0025] Implementation method 1:

[0026] The hydrogen isolation diaphragm involved in this embodiment 1 is a martensitic stainless steel diaphragm with a grade of 00Cr15Ni5. Its initial thickness (i.e., the thickness of the blank before processing) is 0.5 mm, and its chemical composition (by weight percentage) is as follows: Cr: 14-16%, Ni: 4.5-6.5%, Mn: ≤1.0%, Si: ≤1.0%, P: ≤0.035%, S: ≤0.03%, and C: ≤0.03%.

[0027] This embodiment 1 provides a treatment process method for improving the strength and plasticity of a hydrogen isolation diaphragm. This treatment process method is used to treat the above-mentioned hydrogen isolation diaphragm. The goal is to make the treated hydrogen isolation diaphragm meet the following mechanical performance index requirements:

[0028] The yield strength is 848MPa, the tensile strength is 866.6MPa, and the elongation is 11.7%.

[0029] The treatment process method of this embodiment 1 specifically includes the following steps S1 to S2.

[0030] S1, applying high-frequency vibration and static pressure simultaneously to the hydrogen isolation diaphragm (blank), thereby performing high-frequency vibration and static pressure coupling processing on the hydrogen isolation diaphragm.

[0031] The parameters of the applied high-frequency vibration are as follows: the vibration frequency is 14KHz;

[0032] The static pressure applied was selected with the following parameters: a downward pressure of 0.1 mm, a feed speed of 1200 mm / min, and a step distance of 0.06 mm.

[0033] Those skilled in the art will understand that

[0034] The amount of downward pressure refers to controlling the depth of pressure applied by the machining tool to the diaphragm surface, which affects the degree of deformation, residual stress affected area and surface quality;

[0035] The feed rate refers to the speed at which the machining tool moves, affecting machining efficiency and quality.

[0036] The step distance refers to the interval between each movement of the processing tool, which affects the processing coverage, processing efficiency and surface quality.

[0037] For the convenience of accurate description, the hydrogen isolation diaphragm after the treatment in step S1 is defined as a diaphragm after the first treatment.

[0038] It should be noted that the equipment used to apply high-frequency vibration and static pressure to the hydrogen isolation diaphragm is not based on existing technology.

[0039] S2, performing a serpentine rolling process on the once-treated film obtained after the process in step S1, with the number of rolling being 1.

[0040] After the above steps, a finished hydrogen isolation diaphragm is obtained.

[0041] The mechanical properties of the finished hydrogen isolation diaphragm were tested in accordance with GB / T 228.1 "Tensile tests on metallic materials - Part 1 - Test methods at room temperature". Comparing the results before and after treatment, it can be seen that the yield strength, tensile strength and elongation of the hydrogen isolation diaphragm after treatment are improved to 859MPa, 887.8MPa and 11.7% respectively. Figure 1 As shown, this meets the pre-set indicator requirements.

[0042] After cutting the sample, the tissue analysis was carried out. Figure 2 As shown in the figure, it can be seen that after the high-frequency vibration and static pressure coupling treatment, the alloy structure of the hydrogen isolation diaphragm changes, the grains are further refined, and a large number of dislocations are introduced inside the hydrogen isolation diaphragm, thereby improving the strength and hardness of the hydrogen isolation diaphragm and further promoting grain refinement.

[0043] The processing method of this embodiment 1 has the following advantages:

[0044] The processing method of this embodiment 1 performs high-frequency vibration and static pressure coupling treatment on the hydrogen isolation diaphragm, introduces gradient nanostructure and residual compressive stress on the surface of the hydrogen isolation diaphragm, thereby significantly improving the strength and plasticity of the hydrogen isolation diaphragm, reducing the sensitivity to hydrogen embrittlement, and thereby extending the service life of the hydrogen isolation diaphragm in the high-pressure hydrogen diaphragm compressor, and improving the safety and reliability of the equipment.

[0045] In addition, the treatment process of this embodiment 1 has other advantages, as follows:

[0046] 1) Through a simple surface treatment process, gradient nanostructure and residual compressive stress can be introduced into the surface of the hydrogen isolation diaphragm, and the yield strength, tensile strength and elongation are increased, and the surface condition is improved;

[0047] 2) The martensitic stainless steel diaphragm treated by the treatment process of embodiment 1 has a yield point of not less than 850 MPa, a tensile strength of not less than 880 MPa, and an elongation of more than 11%;

[0048] 3) The martensitic stainless steel diaphragm treated by the treatment method of embodiment 1 introduces residual compressive stress, which is expected to inhibit hydrogen atoms in the environment from penetrating along the surface, reduce hydrogen embrittlement sensitivity, and effectively increase the service life of the alloy in a hydrogen environment.

[0049] Implementation 2:

[0050] The technical solution adopted in this embodiment 2 has the same basic concept as that of embodiment 1, but differs in three aspects:

[0051] First, in the second embodiment, the hydrogen barrier diaphragm has an initial thickness (blank thickness) of 0.7 mm.

[0052] Secondly, in the second embodiment, different parameters are used when the high-frequency vibration and static pressure coupling treatment is performed on the hydrogen barrier diaphragm (blank).

[0053] Specifically, in this second embodiment,

[0054] The parameters of the applied high-frequency vibration are as follows: the vibration frequency is 15KHz;

[0055] The static pressure applied was selected with the following parameters: a downward pressure of 0.5 mm, a feed speed of 1000 mm / min, and a step distance of 0.05 mm.

[0056] Thirdly, in the second embodiment, the serpentine rolling process is performed three times.

[0057] The mechanical properties of the hydrogen isolation diaphragm before and after treatment were tested with reference to GB / T 228.1 "Tensile tests on metallic materials - Part 1 - Room temperature test methods". The results showed that the yield strength was 870 MPa, the tensile strength was 892.7 MPa, and the elongation was 12.33%, indicating a significant improvement in strength and plasticity.

[0058] Compared with the processing method of embodiment 1, the processing method of embodiment 2 can further increase the action depth by increasing the frequency, pressing amount and number of repetitions and reducing the feed speed and step, thereby introducing more deformation dislocations, refining the grains, improving the surface quality, and improving the fatigue performance of the diaphragm in a high-pressure hydrogen environment.

[0059] Implementation 3:

[0060] The technical solution adopted in this embodiment 3 has the same basic concept as that of embodiment 1, but differs in three aspects:

[0061] First, in the third embodiment, the hydrogen barrier diaphragm has an initial thickness (blank thickness) of 0.6 mm.

[0062] Secondly, in the third embodiment, different parameters are used when the high-frequency vibration and static pressure coupling process is performed on the hydrogen barrier diaphragm.

[0063] Specifically, in this second embodiment,

[0064] The parameters of the applied high-frequency vibration are as follows: the vibration frequency is 13KHz;

[0065] The static pressure applied was selected with the following parameters: a downward pressure of 0.3 mm, a feed speed of 1100 mm / min, and a step distance of 0.07 mm.

[0066] Thirdly, in the third embodiment, the serpentine rolling process is performed twice.

[0067] The mechanical properties of the hydrogen isolation diaphragm before and after treatment were tested with reference to GB / T 228.1 "Tensile tests on metallic materials - Part 1 - Room temperature test methods". The yield strength, tensile strength and elongation were 852 MPa, 881.5 MPa and 11.5%, respectively, indicating a significant improvement in strength and plasticity.

[0068] Compared with the processing method of embodiment 1, the processing method of embodiment 3 can obtain different surface qualities, organizational structures and stress distributions on the surface of the diaphragm by adjusting different process parameters to achieve different usage requirements.

[0069] The above are only preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Therefore, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A treatment process for improving the strength and plasticity of a hydrogen isolation diaphragm, characterized by: The treatment process comprises: S1, high-frequency vibration and static pressure coupling treatment is performed on the hydrogen isolation diaphragm; S2, performing serpentine rolling processing on the hydrogen isolation diaphragm.

2. The method for improving the strength and plasticity of a hydrogen isolation diaphragm according to claim 1, characterized in that: In step S1, the high-frequency vibration is applied, and the parameters selected are: the vibration frequency is 10 to 15 KHz; In step S1, the static pressure applied has the following parameters: a downward pressure of 0.1 to 0.5 mm, a feed speed of 1000 to 1500 mm / min, and a step distance of 0.05 to 0.1 mm; In step S2, the serpentine rolling process is performed on the hydrogen isolation diaphragm 1 to 3 times.

3. The method for improving the strength and plasticity of a hydrogen isolation diaphragm according to claim 1, characterized in that: In step S1, the high-frequency vibration is applied, and the parameters selected are: the vibration frequency is 14KHz; In step S1, the static pressure applied is as follows: the pressing amount is 0.1 mm, the feed speed is 1200 mm / min, and the step distance is 0.06 mm; In step S2 , the serpentine rolling process is performed on the hydrogen isolation diaphragm once.

4. The method for improving the strength and plasticity of a hydrogen isolation diaphragm according to claim 1, characterized in that: In step S1, the high-frequency vibration is applied, and the parameters selected are: the vibration frequency is 15KHz; In step S1, the static pressure applied has the following parameters: a downward pressure of 0.5 mm, a feed speed of 1000 mm / min, and a step distance of 0.05 mm; In step S2 , the serpentine rolling process is performed on the hydrogen isolation diaphragm three times.

5. The method for improving the strength and plasticity of a hydrogen isolation diaphragm according to claim 1, characterized in that: In step S1, the high-frequency vibration is applied, and the parameters selected are: the vibration frequency is 13KHz; In step S1, the static pressure applied has the following parameters: a downward pressure of 0.3 mm, a feed speed of 1100 mm / min, and a step distance of 0.07 mm; In step S2 , the serpentine rolling process is performed twice on the hydrogen isolation diaphragm.

6. A hydrogen isolation diaphragm, characterized in that: The hydrogen barrier membrane is treated by the treatment process according to any one of claims 1 to 5.

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