A method for evaluating hydrogen barrier coating of hydrogen transmission pipeline based on hydrogen barrier property and hydrogen embrittlement inhibition effect
Patent Information
- Application Number
- CN202611074533.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-07-20
- Publication Date
- 2026-10-23
AI Technical Summary
[0004]本发明的目的是提供一种基于阻氢性能和氢脆抑制效果的输氢管道阻氢涂层评价方法，通过将氢渗透测试与SSRT测试相结合，能够同时反映阻氢涂层降低氢渗透和抑制基体氢脆损伤的效果，解决单一PRF指标或单一SSRT测试结果难以完整评价阻氢涂层防护效果的问题
本发明通过将氢渗透测试结果与SSRT测试结果结合，能够同时评价阻氢涂层降低氢渗透和抑制基体氢脆损伤的效果；通过设置无涂层基体试样与有涂层试样的对比测试，能够减小基体材料差异对评价结果的影响；通过阻氢性能评分B、氢脆抑制率C和协同评价指数E的计算，能够实现不同阻氢涂层在目标输氢工况下的统一判定；通过输出适用工况边界，能够明确评价结果对应的温度、压力、介质组成和基体材料条件；评价结果能够作为阻氢涂层进入后续工程验证的前置筛选依据。该方法解决了单一PRF指标或单一SSRT测试结果难以完整评价阻氢涂层防护效果的问题。
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Abstract
Description
Technical Field
[0001] This invention belongs to the technical field of hydrogen pipeline material protection evaluation, specifically relating to an evaluation method for hydrogen barrier coatings of hydrogen pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect. Background Technology
[0002] Large-scale hydrogen transportation typically relies on newly built pure hydrogen pipelines or hydrogen blending into existing natural gas pipeline networks. During hydrogen transportation, hydrogen atoms can easily penetrate the pipe wall and invade the interior of the pipeline's steel matrix, inducing various failure problems such as hydrogen embrittlement, hydrogen-induced cracking, hydrogen blistering, deterioration of material fracture toughness, and accelerated fatigue crack propagation. This severely shortens the service life of hydrogen transportation pipelines and significantly increases the safety risks of pipeline network operation. Spraying hydrogen-blocking coatings is currently the mainstream protective method to slow down hydrogen permeation into the matrix and improve the long-term reliability of pipelines.
[0003] Current technologies can only conduct hydrogen permeation testing or slow strain rate tensile (SSRT) testing separately, which are disconnected from each other and cannot achieve a unified quantitative assessment of protective performance. Evaluation based solely on hydrogen permeability and the hydrogen permeation reduction factor (PRF) only reflects the coating's basic ability to physically block hydrogen permeation, failing to directly quantify the coating's actual protective effect against hydrogen embrittlement and ductile damage in pipeline steel and against hydrogen-induced cracking. Conversely, SSRT testing alone can only characterize the plasticity decay and hydrogen embrittlement sensitivity of steel in a hydrogen-filled environment, failing to quantitatively reflect the coating's intrinsic hydrogen-blocking performance in preventing hydrogen atoms from penetrating the metal matrix. Furthermore, the difficulty in standardizing test samples and operating conditions for hydrogen permeation and SSRT testing, the lack of a correlation and quantitative model for test data, and the need to set separate sample selection rules result in significant variable interference and an inability to standardize the comprehensive evaluation of the coating's dual protective effect. This makes it difficult to uniformly determine and screen the protective effects of different hydrogen-blocking coatings under conditions corresponding to the target hydrogen transport conditions. Summary of the Invention
[0004] The purpose of this invention is to provide an evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect. By combining hydrogen permeation testing with SSRT testing, the method can simultaneously reflect the effect of the hydrogen barrier coating in reducing hydrogen permeation and suppressing hydrogen embrittlement damage to the substrate, thus solving the problem of relying on a single method. PRF The problem is that indicators or single SSRT test results are insufficient to fully evaluate the protective effect of hydrogen barrier coatings.
[0005] To achieve the above objectives, the technical solution of the present invention is as follows: This invention provides a method for evaluating hydrogen barrier coatings for hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect, comprising the following steps: For the coating to be evaluated, pipeline steel from the same batch was selected as the substrate, and uncoated hydrogen permeation and SSRT samples and coated hydrogen permeation and SSRT samples were prepared respectively. Under the target hydrogen transport conditions, hydrogen permeation tests were conducted on both groups of samples to obtain the hydrogen permeability of the uncoated hydrogen permeation sample. P 0. Hydrogen permeability of coated hydrogen permeation samples P c With hydrogen permeation reduction factor PRF ; Based on hydrogen permeation reduction factor PRF Obtain hydrogen barrier performance score B ; SSRT tests were conducted on the two groups of samples under the reference environment and the target hydrogen transport environment, respectively, to obtain the elongation after fracture of the two types of samples under the corresponding environments. The hydrogen embrittlement index of the uncoated SSRT specimens was calculated based on the elongation after fracture. I HE0 Hydrogen embrittlement index of coated SSRT specimens I HEc and hydrogen embrittlement inhibition rate C ; Based on hydrogen barrier performance score B and hydrogen embrittlement inhibition rate C Calculate the collaborative evaluation index E Based on the synergistic evaluation index E, the recommended conclusions and applicable boundary conditions for the hydrogen barrier coating to be evaluated on the corresponding substrate are output.
[0006] Based on the comparison between uncoated substrates and coated samples, and combined with the evaluation of hydrogen permeation test and SSRT test results, this method can uniformly determine and screen the protective effect of different hydrogen barrier coatings under the conditions corresponding to the target hydrogen transport conditions, and output the corresponding applicable boundary conditions.
[0007] In some other ways, the pipeline steel matrix is selected from one or more of X52, X60, X65, X70, X80, X100 pipeline steel or other metallic materials for hydrogen transportation pipelines; And / or, the coating in the coating to be evaluated is selected from one or more of the following: metal-based coating, ceramic-based coating, two-dimensional material coating, polymer-based composite coating, multilayer composite coating, and gradient composite coating; And / or, the target hydrogen transport condition consists of hydrogen partial pressure, total pressure, temperature and medium, wherein the medium is selected from one or more of hydrogen, natural gas, carbon dioxide, water vapor, hydrogen sulfide and chloride-containing gases.
[0008] In some other ways, hydrogen permeability reduction factor PRF The calculation formula is as follows:
[0009] in, P 0 represents the hydrogen permeability of the uncoated hydrogen permeation sample. Pc The hydrogen permeability is the value of the coated hydrogen permeation sample.
[0010] Hydrogen permeation testing can be performed using existing testing methods, such as electrochemical hydrogen permeation testing methods, gas phase hydrogen permeation testing methods, or other testing methods that can obtain steady-state hydrogen permeation rates.
[0011] In other methods, hydrogen barrier performance is scored. B The calculation formula is as follows: ; in, PRF test The hydrogen permeation reduction factor of the hydrogen barrier coating to be evaluated. PRF ref For reference hydrogen permeation reduction factor and PRF ref >1; when PRF test When ≤1, B Take 0; when PRF test ≥ PRF ref hour, B Take 1.
[0012] SSRT tests were conducted in both a baseline environment and a target hydrogen transport environment. The elongation at break was obtained based on the change in gauge length before and after the test. δ N0 , δ H0 , δ Nc and δ Hc .
[0013] In some other ways, the hydrogen embrittlement index of uncoated SSRT specimens I HE0 The calculation formula is as follows: ; in, δ N0 Elongation after fracture of uncoated SSRT specimens under nitrogen atmosphere (reference environment) δ N0 , δ H0 Elongation at break of uncoated SSRT specimens in a hydrogen environment; And / or, the hydrogen embrittlement index of coated SSRT specimens. I HEc The calculation formula is as follows: ; in, δNc Elongation after fracture of coated SSRT specimens under nitrogen atmosphere in a reference environment. ， δ Hc Elongation after fracture of coated SSRT specimens in a hydrogen environment δ Hc .
[0014] In some other methods, the formula for calculating the hydrogen embrittlement suppression rate is as follows: ; in, I HE0 The hydrogen embrittlement index of the uncoated SSRT sample. I HEc To determine the hydrogen embrittlement index of the coated SSRT sample, a numerical correction is applied to the calculated hydrogen embrittlement inhibition rate: if the calculated value is greater than 1, then the hydrogen embrittlement inhibition rate is... C Set the value to 1; if the calculated value is less than 0, then the hydrogen embrittlement suppression rate is... C Take 0.
[0015] In some other methods, the formula for calculating the collaborative evaluation index E is as follows: ; in, w 1 and w 2 represents the hydrogen barrier performance score. B and hydrogen embrittlement inhibition rate C The weights, and w 1+ w 2 = 1.
[0016] In one implementation, w 1 = 0.50 w 2 = 0.50; in other embodiments, w 1 and w 2. Determined based on the target hydrogen transport conditions, evaluation objectives, or engineering requirements.
[0017] In some other ways, the evaluation results include at least: PRF Hydrogen barrier performance rating B , I HE0 , I HEc Hydrogen embrittlement inhibition rate C Collaborative evaluation index E The ranking results or grade conclusions, recommended conclusions, and applicable boundary conditions.
[0018] The applicable boundary conditions include at least hydrogen partial pressure, total pressure, temperature, medium composition, substrate material conditions, and coating thickness range.
[0019] In some other ways, E ≥0.80, preferred; 0.60≤ E <0.80, conditionally recommended; E <0.60, not recommended.
[0020] In some other methods, before conducting hydrogen permeation and SSRT tests, sample validity verification is performed to confirm that the coating on coated samples covers the effective hydrogen permeation test area and the effective gauge length area on SSRT samples. Sample validity verification is only used to determine whether the test data should be included in subsequent calculations.
[0021] The beneficial effects of this invention are: This invention combines hydrogen permeation test results with SSRT test results to simultaneously evaluate the effectiveness of hydrogen-barrier coatings in reducing hydrogen permeation and inhibiting hydrogen embrittlement damage to the substrate. By setting up comparative tests between uncoated and coated substrate samples, the influence of substrate material differences on the evaluation results can be reduced. Hydrogen barrier performance is scored... B Hydrogen embrittlement inhibition rate C and collaborative evaluation index E The calculations enable unified determination of different hydrogen barrier coatings under target hydrogen transport conditions; by outputting the applicable operating condition boundaries, the corresponding temperature, pressure, medium composition, and substrate material conditions can be clearly defined; the evaluation results can serve as a preliminary screening basis for hydrogen barrier coatings to enter subsequent engineering verification. This method solves the problem of single... PRF The problem is that indicators or single SSRT test results are insufficient to fully evaluate the protective effect of hydrogen barrier coatings. Attached Figure Description
[0022] The accompanying drawings, which form part of this invention, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an improper limitation of the invention.
[0023] Figure 1 Here is a flowchart of the overall evaluation method; Figure 2 Hydrogen barrier performance scoring index B Calculation flowchart; Figure 3 Hydrogen embrittlement inhibition rate scoring index C Calculation flowchart; Figure 4 For collaborative evaluation indicators E Flowchart for calculating and evaluating results output. Detailed Implementation
[0024] Those skilled in the art will understand that the following embodiments are for illustrative purposes only and should not be construed as limiting the scope of the invention. Specific conditions not specified in the embodiments are performed under conventional conditions or conditions recommended by the manufacturer. Components whose manufacturers are not specified are all commercially available conventional products.
[0025] Example 1 A method for evaluating hydrogen barrier coatings for hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect is proposed. This method is based on comparative testing of uncoated substrate samples and coated samples from the same batch, and sequentially completes the following steps: determining the target hydrogen transport conditions, preparing comparative samples, confirming sample effectiveness, and conducting hydrogen permeation testing. PRF Calculation, SSRT test, hydrogen embrittlement index calculation, hydrogen embrittlement inhibition rate calculation, synergistic evaluation index calculation, and evaluation result output, such as Figure 1 As shown, it includes the following steps: S1: Determine the hydrogen barrier coating to be evaluated, the pipeline steel substrate, and the target hydrogen transport conditions. The hydrogen barrier coating to be evaluated is selected from metal-based coatings, ceramic-based coatings, two-dimensional material coatings, polymer-based composite coatings, multilayer composite coatings, or gradient composite coatings.
[0026] The pipeline steel matrix is selected from X52, X60, X65, X70, X80, X100 pipeline steel or other metallic materials used for hydrogen transportation pipelines.
[0027] The target hydrogen transport condition consists of hydrogen partial pressure, total pressure, temperature, and medium. The medium is selected from one or more of hydrogen, natural gas, carbon dioxide, water vapor, hydrogen sulfide, and chloride-containing gases.
[0028] S2: Preparation of comparative samples with and without coating. Uncoated hydrogen permeation samples, coated hydrogen permeation samples, uncoated SSRT samples, and coated SSRT samples were prepared from the same batch of pipeline steel materials to reduce the influence of matrix material differences on the evaluation results.
[0029] S3: Confirm the validity of the sample Sample validity verification is used to determine whether test data should be included in subsequent calculations. Sample validity verification includes at least: (1) The coating of coated specimens should cover the effective test area of hydrogen permeation specimens and the effective gauge length area of SSRT specimens; (2) The coating thickness is within the preparation control range determined before the evaluation of the coating system; (3) Through cracks, through holes or peeling defects do not cover or destroy the effective test area of the hydrogen permeation specimen and the effective gauge length area of the SSRT specimen. (4) Hydrogen permeation testing can obtain stable permeation data; (5) The elongation after fracture results obtained by SSRT test are valid.
[0030] When through-cracks, piercing holes, or peeling defects cover or destroy the effective hydrogen permeation test area or the effective gauge length area under slow strain rate tension, the sample group is excluded from subsequent calculations. When stable hydrogen permeation data is not obtained from the hydrogen permeation test, or the elongation after fracture result obtained from the SSRT test is invalid, the data from this group is not used for calculating the synergistic evaluation index E. Sample validity confirmation is not included in the hydrogen barrier performance scoring. B Hydrogen embrittlement inhibition rate C and collaborative evaluation index E The calculation.
[0031] S4: Perform hydrogen permeation testing and calculate... PRF Hydrogen permeability tests were conducted on uncoated and coated hydrogen permeability samples under target or simulated hydrogen transport conditions to obtain the hydrogen permeability of the uncoated substrate. P 0 and hydrogen permeability of coated samples P c And calculate the hydrogen permeation reduction factor according to the following formula. PRF : ; The hydrogen permeation test can be performed using electrochemical hydrogen permeation testing methods, gas phase hydrogen permeation testing methods, or other testing methods that can obtain steady-state hydrogen permeation rates.
[0032] S5: According to PRF Determine hydrogen barrier performance score B Hydrogen barrier performance rating index B The calculation flowchart is as follows Figure 2 As shown, the hydrogen barrier coating was evaluated using a benchmark comparison mode: ; in, PRF test The hydrogen permeation reduction factor of the hydrogen barrier coating to be evaluated. PRF ref For reference, hydrogen permeation reduction factor, and PRF ref >1. When PRF test When ≤1, B Take 0; when PRF test ≥ PRF ref hour, B Take 1.
[0033] PRF refThe reference hydrogen permeation reduction factor, which is determined before evaluation, can be derived from any of the following sources: (1) Objectives pre-defined before evaluation by the evaluation plan, enterprise technical specifications, project testing plan, or engineering objectives. PRF value; (2) The hydrogen permeability measured by a validated engineering benchmark coating or a similar hydrogen barrier coating under the same substrate material, the same hydrogen permeability testing method, and the same target hydrogen transport conditions. PRF value; (3) References reported in publicly available literature PRF The value is determined.
[0034] when PRF ref When the reference PRF value is derived from publicly available literature, the reference value from the publicly available literature shall be used as the reference value. PRF The values should at least meet the following comparability conditions: a. In publicly available documents PRF Definitions and those in this invention PRF The definition is consistent, both referring to the ratio of hydrogen permeability of the uncoated substrate to the hydrogen permeability of the coated sample; b. The hydrogen permeation test method used in the published literature is the same as the hydrogen permeation test method used in the hydrogen barrier coating to be evaluated. Both are the same one among the gas phase hydrogen permeation test method, electrochemical hydrogen permeation test method, or other similar steady-state hydrogen permeation test methods. c. The coating substrate material in the published literature is the same steel grade or pipeline steel material within the same strength grade range as the substrate material used in the hydrogen barrier coating to be evaluated; d. The coating system in the published literature belongs to the same coating system as the hydrogen barrier coating to be evaluated or has the same main hydrogen barrier functional layer; e. The test temperature, hydrogen partial pressure or hydrogen filling conditions, sample thickness and coating thickness in the published literature are the same as the test conditions of the hydrogen barrier coating to be evaluated, or are within the allowable deviation range determined before evaluation.
[0035] References reported in publicly available literature PRF If the value does not meet the above comparability conditions, the value reported in the publicly available literature should not be used as the benchmark. PRF ref .
[0036] Specifically, assuming the hydrogen permeation reduction factor is obtained, the study is divided into a batch-based ranking mode and a benchmark control mode; among them, the hydrogen barrier performance scoring index in the batch-based ranking mode... B i =ln( PRF test i ) / ln( PRF ref ); and whenPRF test-i When ≤1, B i The value is 0; when all candidate coatings in the same batch... PRF If none of the values are greater than 1, then no relative ranking evaluation will be conducted.
[0037] Formula for calculating hydrogen barrier performance score in benchmark mode: B =ln( PRF test ) / ln( PRF ref );Require PRF ref >1; when PRF test When ≤1, B Take 0; when PRF test ≥ PRF ref hour, B Set the score to 1. After the two scoring branches complete their calculations, output a unified hydrogen barrier performance score. B .
[0038] S6: Perform SSRT testing and obtain elongation after fracture. SSRT tests were conducted using uncoated and coated SSRT specimens under reference and target hydrogen transport conditions or simulated target hydrogen transport conditions, respectively. The results were obtained based on the change in gauge length before and after specimen fracture. (1) Elongation after fracture of uncoated substrate under reference environment (nitrogen) δ N0 ; (2) Elongation after fracture of uncoated substrate in target hydrogen environment δ H0 ; (3) Elongation at break of coated samples under reference environment (nitrogen) δ Nc ; (4) Elongation after fracture of coated samples in target hydrogen environment δ Hc .
[0039] The test environments in steps S4 and S6 are the same, or the two meet the preset correspondence in terms of hydrogen partial pressure, total pressure, temperature and medium composition.
[0040] S7: Calculate the hydrogen embrittlement index The hydrogen embrittlement index of an uncoated substrate is calculated using the following formula: ; The hydrogen embrittlement index of coated samples is calculated using the following formula: ; S8: Calculate hydrogen embrittlement suppression rate C The calculation flowchart for the hydrogen embrittlement inhibition rate score index C is as follows: Figure 3 As shown, in obtaining I HE0 and I HEc Under the given conditions, the effectiveness of the hydrogen embrittlement index is determined: if I HE0 > I HEc If the hydrogen embrittlement index is valid, then the hydrogen embrittlement suppression rate is calculated. C， Hydrogen embrittlement inhibition rate C Calculate according to the following formula: ; when I HEc When <0, it indicates that the coated SSRT sample did not exhibit plasticity loss relative to the reference environment under the target hydrogen environment, calculated according to the above formula. C If the value is greater than 1, the hydrogen embrittlement suppression effect is calculated at the upper limit. C Take 1; when I HE0 < I HEc If the calculated C is less than 0, the SSRT test data and sample validity need to be verified. If the verification reveals one or more of the following: abnormal elongation after fracture measurement, incomplete coating coverage of the effective gauge length area of SSRT, sample preparation defects, or abnormal testing environment, then return to step S6 to obtain the elongation after fracture again. If the verification does not find any of the above abnormalities, then this situation is also considered as a valid hydrogen embrittlement index, indicating that the coated SSRT sample does not show a hydrogen embrittlement suppression effect compared to the uncoated SSRT sample, and C is set to 0.
[0041] S9: Calculate the collaborative evaluation index E The flowchart for calculating the collaborative evaluation index E and outputting the evaluation results is as follows: Figure 4 As shown, the hydrogen barrier performance score was obtained. B and hydrogen embrittlement inhibition rate C Under the premise of obtaining hydrogen barrier performance scores respectively B and hydrogen embrittlement inhibition rate C weight w 1 and w 2 and w 1+ w 2 = 1.
[0042] The collaborative evaluation index is calculated according to the following formula. E : ; in, w 1 and w 2 represents the hydrogen barrier performance score. B and hydrogen embrittlement inhibition rate C The weights, and w 1+ w 2 = 1. w 1 and w 2. Determined based on the target hydrogen transport conditions, evaluation objectives, or engineering requirements. For example, w 1 = 0.50 w 2 = 0.50.
[0043] S10: Output evaluation results and applicable working condition boundaries In obtaining the collaborative evaluation index E Under the premise of ensuring quality, the evaluation output method is determined: it is divided into a batch ranking mode and a benchmark comparison mode; if the batch ranking mode is recommended, it is based on the collaborative evaluation index. E Sort by numerical value and select E Coatings with higher values and effective samples are recommended coatings for the target operating conditions; if a benchmark comparison mode is used, the classification is simplified according to... E ≥0.80, preferred; 0.60≤ E＜ 0.80, conditionally recommended; E＜ 0.60, not recommended. Then output the evaluation result.
[0044] Specifically, "preferred recommendation", "conditional recommendation" and "not recommended" are experimental evaluation conclusions obtained based on the evaluation method of this invention.
[0045] The terms "Preferred Recommendation" and "Conditional Recommendation" indicate that the hydrogen-barrier coating being evaluated meets the pre-defined recommended range in its synergistic evaluation index under the experimental test conditions, making it a priority candidate for subsequent engineering adaptability verification or engineering application demonstration. "Conditional Recommendation" indicates that the hydrogen-barrier coating exhibits certain hydrogen-barrier performance and hydrogen embrittlement suppression effects under the experimental test conditions, but the synergistic evaluation results do not meet the preferred recommendation level. Further performance optimization is required before engineering adaptability verification or engineering application demonstration, and it can only be considered as an alternative recommendation. "Not Recommended" indicates that the hydrogen-barrier coating being evaluated does not meet the pre-defined evaluation requirements under the experimental test conditions and is not recommended for subsequent engineering adaptability verification or engineering application demonstration. These evaluation conclusions are not directly equivalent to the final conclusion of engineering service qualification.
[0046] The evaluation results should include at least the following: PRF Hydrogen barrier performance rating B , I HE0 , I HEcHydrogen embrittlement inhibition rate C Collaborative evaluation index E The ranking results or grade conclusions, recommended conclusions, and applicable boundary conditions.
[0047] The applicable boundary conditions include at least hydrogen partial pressure, total pressure, temperature, medium composition, substrate material conditions, and coating thickness range. The evaluation results are used to determine whether the hydrogen barrier coating under evaluation should undergo subsequent bending, fatigue, corrosion, pressure cycling, or long-term service verification, and are not directly extrapolated to unverified operating conditions.
[0048] The following data are exemplary data, used only to illustrate the parameter acquisition, calculation process and result output method of the evaluation method of the present invention, and do not represent a limitation on the performance of a specific hydrogen barrier coating, nor do they constitute a limitation on the scope of protection of the present invention.
[0049] A benchmark evaluation of a hydrogen barrier coating was conducted using X80 pipeline steel as the substrate. The target hydrogen transport condition was set as a hydrogen-doped environment with a hydrogen partial pressure of [value missing]. P 1. Total pressure is P t1 The temperature is T The target PRF value for the hydrogen permeation reduction coating to be evaluated in engineering applications is 8.0, therefore the reference hydrogen permeation reduction factor is used. PRF ref It is 8.0.
[0050] It should be noted that, PRF ref It is not arbitrarily set during the calculation process, but needs to be determined in advance before the evaluation. Its sources include: (1) The objectives specified in advance in the evaluation plan, enterprise technical specifications, project test plan or engineering target requirements. PRF value; (2) The hydrogen barrier coating or similar hydrogen barrier coating has been verified and measured under comparable test conditions. PRF value; (3) and references reported in publicly available literature under the same or comparable test conditions. PRF value.
[0051] In Example 1 PRF ref =8.0 is only an illustrative reference value used to illustrate the hydrogen barrier performance score under the benchmark comparison mode. B The calculation process described herein does not represent a limitation on specific coating performance or engineering acceptance standards.
[0052] Hydrogen permeation test results: 1. Hydrogen permeability of uncoated substrate P 0 = 1.20 × 10 -9 ; 2. Hydrogen permeability of coated samples P c =2.40×10 -10 .
[0053] According to the formula: PRF = P 0 / P c =5.0; but: B =ln(5.0) / ln(8.0)≈0.774.
[0054] SSRT test results: (1) Elongation after fracture of uncoated substrate under reference environment (nitrogen) δ N0 , δ N0 =20.0%; (2) Elongation after fracture of uncoated substrate in target hydrogen environment δ H0 , δ H0 =12.0%; (3) Elongation at break of coated samples under reference environment (nitrogen) δ Nc , δ Nc =19.5%; (4) Elongation after fracture of coated samples in target hydrogen environment δ Hc , δ Hc =16.5%; Then: Hydrogen embrittlement index of uncoated substrate I HE0 =(1-12.0 / 20.0)×100%=40.0%; Hydrogen embrittlement index of coated samples I HEc =(1-16.5 / 19.5)×100%≈15.38%; Hydrogen embrittlement inhibition rate C =(40.0-15.38) / 40.0≈0.6155; when w 1 = 0.50 w When 2 = 0.50: E =0.50×0.774+0.50×0.6155≈0.6948; Based on the E value (0.60≤ E(<0.80), the output recommendation conclusion is "conditional recommendation". Specifically, under the set experimental test conditions, the hydrogen barrier coating to be evaluated exhibits certain hydrogen barrier performance and hydrogen embrittlement suppression effect, and can be used as a candidate recommended coating. If it is to proceed to subsequent engineering adaptability verification, the coating still needs further performance optimization.
[0055] The applicable boundary conditions for the output recommendation conclusion: The "conditional recommendation" conclusion is based on the hydrogen partial pressure, total pressure, temperature, medium composition, substrate material conditions and coating thickness range during the experimental test, and is not directly extrapolated to unverified operating conditions.
[0056] Meanwhile, "coating thickness" is one of the applicable boundaries of the evaluation results, used to ensure that the evaluation conclusions of this embodiment correspond to the corresponding coating preparation state, and is not used as a score for hydrogen barrier performance. B Hydrogen embrittlement inhibition rate C Or collaborative evaluation index E The calculation indicators.
[0057] Example 2 Three candidate hydrogen barrier coatings were evaluated and ranked within the same batch of X80 pipeline steel substrates. The results of hydrogen permeation and SSRT tests are summarized in Table 1 below.
[0058] Table 1. Results and Evaluation Indicators of Hydrogen Permeability Test and SSRT Test
[0059] in, E according to w 1 = 0.50 w The result is calculated as 2 = 0.50. This is based on the collaborative evaluation index in Table 1. E Based on the size order, the ranking results are: Candidate Coating 1, Candidate Coating 2, Candidate Coating 3. If the sample corresponding to Candidate Coating 1 meets the sample validity confirmation requirements, then Candidate Coating 1 is output as the preferred recommended coating under the target hydrogen transport conditions.
[0060] Example 3 For natural gas blending and hydrogen transportation environments, the hydrogen partial pressure is set as follows: P 2. Total pressure is P t2 The temperature is T 2. The medium consists of natural gas, hydrogen, carbon dioxide, and water vapor, and the substrate material is X70 pipeline steel. After completing steps S1 to S9, if the synergistic evaluation index of the hydrogen-barrier coating to be evaluated is obtained... E =0.82, then the following conclusion is output: (1) The hydrogen barrier coating under operating conditions P 2. P t2 ,T 2. Based on the medium composition and X70 pipeline steel matrix conditions, it is determined to be the preferred recommendation; (2) The evaluation results are only applicable to the currently set hydrogen partial pressure, total pressure, temperature, medium composition, substrate material conditions and coating thickness range; (3) The evaluation results are not directly extrapolated to unverified conditions such as higher hydrogen partial pressure, higher total pressure, higher temperature, different media composition, or different matrix materials.
[0061] The above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A method for evaluating hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect, characterized in that, Includes the following steps: For the coating to be evaluated, pipeline steel from the same batch was selected as the substrate, and hydrogen permeation and slow strain rate tensile SSRT specimens without coating and hydrogen permeation and SSRT specimens with coating were prepared respectively. Under the target hydrogen transport conditions, hydrogen permeability tests were conducted on two groups of samples, one with coating and one without, to obtain the hydrogen permeability of the uncoated sample. P 0. Hydrogen permeability of coated hydrogen permeation samples P c With hydrogen permeation reduction factor PRF ; Based on hydrogen permeation reduction factor PRF Obtain hydrogen barrier performance score B ; SSRT tests were conducted on the two groups of samples under the reference environment and the target hydrogen transport environment, respectively, to obtain the elongation after fracture of the two types of samples under the corresponding environments. The hydrogen embrittlement index of the uncoated SSRT specimens was calculated based on the elongation after fracture. I HE0 Hydrogen embrittlement index of coated SSRT specimens I HEc and hydrogen embrittlement inhibition rate C ; Based on hydrogen barrier performance score B and hydrogen embrittlement inhibition rate C Calculate the collaborative evaluation index E And based on the collaborative evaluation index E Output recommended conclusions and applicable boundary conditions for the hydrogen barrier coating to be evaluated on the corresponding substrate.
2. The evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect according to claim 1, characterized in that, The pipeline steel matrix is selected from one or more of X52, X60, X65, X70, X80, X100 pipeline steel or other metallic materials for hydrogen transportation pipelines; And / or, the coating in the coating to be evaluated is selected from one or more of the following: metal-based coating, ceramic-based coating, two-dimensional material coating, polymer-based composite coating, multilayer composite coating, and gradient composite coating; And / or, the target hydrogen transport condition consists of hydrogen partial pressure, total pressure, temperature and medium, wherein the medium is selected from one or more of hydrogen, natural gas, carbon dioxide, water vapor, hydrogen sulfide and chloride-containing gases.
3. The evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect according to claim 1, characterized in that, The hydrogen permeability reducing factor PRF The calculation formula is as follows: ； in, P 0 represents the hydrogen permeability of the uncoated hydrogen permeation sample. P c The hydrogen permeability is the hydrogen permeability of the coated hydrogen permeation sample.
4. The evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect according to claim 1, characterized in that, Hydrogen barrier performance rating B The calculation formula is as follows: ； in, PRF test The hydrogen permeation reduction factor of the hydrogen barrier coating to be evaluated; PRF ref For reference hydrogen permeation reduction factor and PRF ref >1; when PRF test When ≤1, B Take 0; when PRF test ≥ PRF ref hour, B Take 1.
5. The evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect according to claim 1, characterized in that, Hydrogen embrittlement index of the uncoated SSRT sample I HE0 The calculation formula is as follows: ； in, δ N0 Elongation at break of uncoated SSRT specimens under a reference environment (nitrogen). δ H0 Elongation after fracture of uncoated SSRT specimens in a hydrogen environment ； And / or, the hydrogen embrittlement index of the coated SSRT specimen. I HEc The calculation formula is as follows: ； in, δ Nc The elongation at break of the coated SSRT specimen under a reference environment (nitrogen) is given. δ Hc Elongation at break of the coated SSRT sample in a hydrogen environment.
6. The evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect according to claim 1, characterized in that, The formula for calculating the hydrogen embrittlement suppression rate is as follows: ； in, I HE0 The hydrogen embrittlement index of the uncoated SSRT sample. I HEc The hydrogen embrittlement index of the coated SSRT sample; Numerical correction is applied to the calculated hydrogen embrittlement suppression rate: if the calculated value is greater than 1, then the hydrogen embrittlement suppression rate is... C Set the value to 1; if the calculated value is less than 0, then the hydrogen embrittlement suppression rate is... C Take 0.
7. The evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect according to claim 1, characterized in that, The formula for calculating the collaborative evaluation index E is as follows: ； in, w 1 and w 2 represents the hydrogen barrier performance score. B and hydrogen embrittlement inhibition rate C The weights, and w 1+ w 2 = 1.
8. The evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect according to claim 1, characterized in that, The evaluation results should include at least the following: PRF Hydrogen barrier performance rating B , I HE0 , I HEc Hydrogen embrittlement inhibition rate C Collaborative evaluation index E The ranking results or grade conclusions, recommendation conclusions, and applicable boundary conditions; And / or, applicable boundary conditions include at least hydrogen partial pressure, total pressure, temperature, medium composition, substrate material conditions, and coating thickness range.
9. The evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect according to claim 1, characterized in that, E ≥0.80, preferred; 0.60≤ E＜ 0.80, conditionally recommended; E＜ 0.60, not recommended.
10. The evaluation method for hydrogen barrier coatings in hydrogen transport pipelines based on hydrogen barrier performance and hydrogen embrittlement suppression effect according to claim 1, characterized in that, Before conducting hydrogen permeation and SSRT tests, the validity of the samples is confirmed to ensure that the coating of coated samples covers the effective test area of hydrogen permeation samples and the effective gauge length area of SSRT samples. The validity of the test sample is only used to determine whether the test data should be included in subsequent calculations.