CN111235369A - Method for improving hydrogen embrittlement resistance of 304 austenitic stainless steel - Google Patents
Method for improving hydrogen embrittlement resistance of 304 austenitic stainless steel Download PDFInfo
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- CN111235369A CN111235369A CN201811444909.0A CN201811444909A CN111235369A CN 111235369 A CN111235369 A CN 111235369A CN 201811444909 A CN201811444909 A CN 201811444909A CN 111235369 A CN111235369 A CN 111235369A
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0205—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips of ferrous alloys
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0221—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
- C21D8/0236—Cold rolling
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D8/00—Modifying the physical properties by deformation combined with, or followed by, heat treatment
- C21D8/02—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
- C21D8/0247—Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
- C21D8/0273—Final recrystallisation annealing
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- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D2211/00—Microstructure comprising significant phases
- C21D2211/001—Austenite
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- Thermal Sciences (AREA)
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- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
The invention discloses a method for improving the hydrogen embrittlement resistance of 304 austenitic stainless steel, which comprises the following steps of firstly carrying out solid solution treatment to homogenize the structure of a material; subsequently, the treated material is rolled by a double-roller mill, so that stress is introduced into the material; and finally, annealing the rolled material by using a tube furnace. According to the invention, the grain boundary characteristic distribution is optimized by carrying out the thermomechanical treatment on the raw material, so that the hydrogen embrittlement resistance is improved from the material source, and the cost is saved.
Description
Technical Field
The invention belongs to a technology for enhancing the performance of 304 austenitic stainless steel, and particularly relates to a method for improving the hydrogen embrittlement resistance of 304 austenitic stainless steel.
Background
At present, the fields of aviation, ocean, petroleum, nuclear industry, hydrogen energy and the like are in the rapid development period, and the fields all face the problem of hydrogen embrittlement, so that the high-strength stainless steel in the hydrogen environment is required to have better performance. For example, the alloy used by spacecrafts, the steel used by ships, oil and gas pipelines, hydrogen storage pressure vessels, nuclear reactor walls and other materials need to have high strength and toughness and low hydrogen embrittlement sensitivity, thereby ensuring safe and reliable service of the materials. 304 stainless steel is a material with better corrosion resistance, and is more difficult to generate hydrogen embrittlement compared with low alloy steel and carbon steel, but under a high-pressure hydrogen environment, hydrogen embrittlement phenomenon is inevitably generated by many metal materials, and even 304 stainless steel with lower hydrogen embrittlement sensitivity can generate hydrogen embrittlement corrosion.
Although the traditional measures for preventing hydrogen embrittlement can inhibit the generation of hydrogen embrittlement to a certain extent and reduce the harm of hydrogen embrittlement, the measures have certain limitations, the cost for controlling the impurity content of steel is huge, large-sized steel devices cannot be integrally tempered, the influence of a method for storing at room temperature on hydrogen embrittlement is limited, the consumption of electroplating is considerable, and the process parameters for changing the tensile stress state of the products are difficult to control, so that a new method for preventing stainless steel hydrogen embrittlement needs to be developed urgently. The grain boundary engineering method can improve the grain boundary characteristic distribution of the 304 stainless steel through thermomechanical treatment, thereby improving the hydrogen embrittlement resistance of the stainless steel, and the method is more economical and convenient than the traditional method, so that the method has great development space. At present, no report that grain boundary characteristic distribution of 304 austenitic stainless steel is controlled by using a thermomechanical treatment mode so as to improve the hydrogen embrittlement resistance of the stainless steel exists at home and abroad.
The literature (royal sea, petrochemical plants, 2018.5, 47(5)) applies coatings on steel surfaces by chemical, electrochemical or metallurgical methods, forming surface barriers that prevent or slow down the permeation of hydrogen into the matrix. However, electroplating itself is a hydrogen charging process, the hydrogen content in the steel after electroplating will increase, especially the hydrogen embrittlement sensitivity of the high-strength steel after cadmium plating or zinc-cadmium alloy plating will increase obviously, and the electroplating cost is also higher.
Disclosure of Invention
The invention aims to provide a method for improving the hydrogen embrittlement resistance of 304 austenitic stainless steel, so that the hydrogen embrittlement resistance of 304 stainless steel is improved under the condition of low cost.
The technical scheme for realizing the purpose of the invention is as follows: method for improving hydrogen embrittlement resistance of 304 austenitic stainless steel
Firstly, carrying out solid solution treatment to homogenize the structure of the material; subsequently, the two-roll mill pair is used for processing
Rolling the latter material so as to introduce stresses into the interior of the material; finally using tube furnace to roll
And carrying out annealing treatment on the material. The method specifically comprises the following steps:
(1) placing the 304 stainless steel plate in a tube furnace, and heating to TSolid solutionRear heat preservation tSolid solutionTime, solid solution is carried out
Processing;
(2) quickly cooling the 304 stainless steel plate subjected to solution treatment in a liquid cooling medium to obtain the finished product
Obtaining a unidirectional austenite structure;
(3) placing the plate subjected to the treatment in a double-roller mill, and carrying out unidirectional cold rolling;
(4) repeating the operation of the step (3), and carrying out one-way multi-pass cold rolling until the final deformation amount is 5-9%;
(5) putting the plate treated in the step (4) into a tube furnace, and withdrawing the plate at 1050-1100 DEG C
Treating with fire for 5-10 min;
(6) the annealed sheet is placed in a liquid cooling medium for rapid cooling, thereby obtaining the product with good quality
Stainless steel sheet material with good hydrogen embrittlement resistance.
Further, in the step (1), T in the solution treatment of the 304 stainless steel plateSolid solutionThe temperature range is 1000-1100 ℃, and the solution treatment time tSolid solutionThe value range is 25-35 min.
Further, in the step (2), the liquid cooling medium is an ice-water mixture to obtain a faster cooling speed, so that a single-phase austenite structure is obtained.
Furthermore, in the step (3), the rolling reduction range of the double-roller mill is 0.05-0.15mm, so as to avoid the work hardening phenomenon caused by excessive single deformation.
Further, in the step (4), the final deformation amount is preferably 7%.
Further, in the step (5), the plate was annealed at 1075 ℃ for 7 min.
Further, in the step (6), the liquid cooling medium is an ice-water mixture.
Compared with the prior art, the invention has the remarkable advantages that:
(1) the hydrogen embrittlement sensitivity of the 304 stainless steel is reduced, and the hydrogen embrittlement resistance of the treated material is superior to that of the material treated by the traditional hydrogen embrittlement prevention method;
(2) simple operation, high production efficiency, low production cost and no chemical pollution.
Drawings
Fig. 1(a) is a distribution plot of grain boundary characteristics for untreated 304 austenitic stainless steel.
Fig. 1(b) is a distribution diagram of grain boundary characteristics of the treated 304 austenitic stainless steel.
Detailed Description
The invention is based on the concept of grain boundary engineering, and controls the grain boundary characteristic distribution of the material by cold rolling and tube furnace annealing, thereby improving the hydrogen embrittlement resistance of the 304 austenitic stainless steel. The method comprises the following specific steps:
(1) putting a 304 stainless steel plate into a tube furnace, and carrying out solution treatment for 30min at 1050 ℃;
(2) quenching the sample after the solution treatment by using an ice-water mixture;
(3) placing the plate after solid solution in a double-roller mill, and carrying out unidirectional multi-pass cold rolling, wherein the single pressing amount is 0.1 mm;
(4) repeating the operation of the step 2 until the deformation reaches 7 percent;
(5) placing the rolled plate in a tube furnace, and annealing the plate, wherein the annealing temperature is 1050-1100 ℃, and the annealing time is 7 min;
(6) and quenching the annealed sample by using an ice-water mixture.
In the following examples, the optimization effect of the material grain boundary characteristic distribution is expressed by a special grain boundary proportion (%), and the higher the value is, the better the optimization effect of the grain boundary is; the hydrogen embrittlement resistance of the material is expressed by the hydrogen induced elongation loss (%), and a smaller value indicates a better hydrogen embrittlement resistance.
δL＝(δO-δH)/δO×100％
In the formula: deltaLRepresents the hydrogen-induced elongation reduction rate, delta, of the materialORepresents the elongation, delta, of the material when not charged with hydrogenHIndicating the elongation of the material after charging with hydrogen.
Examples
And (3) putting the sample into a GSL-1600 type tubular furnace with the temperature of 1050 ℃ for heat preservation for 30min, and then taking out the sample to be quenched by an ice-water mixture to obtain the material subjected to solid solution treatment. The cold rolling equipment is a double-roller mill, the diameter of the roller is phi 380mm, and the rotating speed of the roller is 18 m/min. The cold rolling deformation is 5-12%, the cold rolled steel is annealed for 3-10min at 1025-1125 ℃ respectively, the annealing is carried out in a GSL-1600 type tube furnace with preset temperature, and then quenching treatment is carried out by using an ice water mixture. The proportion of low-energy CSL (double site lattice) special grain boundaries in the treated sample changes with the annealing temperature, and specific test results are shown in Table 1.
The treated samples were prepared as standard tensile samples and then electrochemically charged to produce hydrogen embrittlement. Electrochemical hydrogen charging was performed on an LK2005 electrochemical workstation. The hydrogen charging current density is 50mA cm-1The charging time is 24h, and the charging solution is 0.5 mol.L-1H of (A) to (B)2SO4Adding 0.1 vol% of CS2As a poisoning agent, the action of the poisoning agent is to make the material more susceptible to hydrogen embrittlement. The whole electrochemical hydrogen charging process is carried out at room temperature, graphite is used as an anode during hydrogen charging, a sample is used as a cathode, and hydrogen atoms are generated on the surface of the sample and diffused into the material by utilizing the electrochemical reaction in the electrolysis process, so that the material is hydrogen brittle.
All samples were subjected to a tensile test in a Shimadzu AGS-X electronic universal tester at a tensile rate of 0.5 mm. multidot.min-1The experimental data are shown in table 1.
TABLE 1 test results for samples at different annealing temperatures
TABLE 2 test results of samples with different deformation
TABLE 3 test results for samples with different annealing times
Comparative example
In order to compare the differences in the structure and performance between the treated material and the original material, the original material was sensitized at 650 ℃ for 2h, and then subjected to electrochemical hydrogen charging and tensile tests at normal temperature, with the test results shown in table 1. It can be found that the hydrogen embrittlement resistance of the sample with optimized grain boundary characteristic distribution is improved to a certain extent compared with the hydrogen embrittlement resistance of the raw material under the same sensitization condition.
Preparing the material treated by the method into a standard metallographic specimen, and testing the grain boundary characteristic distribution of the material by utilizing a back scattering electron diffraction technology after grinding, mechanical polishing and electrolytic polishing, wherein the proportion of special grain boundaries in the structure reaches 75%; under the same sensitization condition, the hydrogen-induced elongation loss rate is obviously reduced relative to the parent metal, and the hydrogen brittleness resistance of the material is improved to a certain extent.
Fig. 1(a) shows the distribution of grain boundary characteristics in the raw material structure, wherein the proportion of special grain boundaries (Σ ≦ 29) is 41%, and fig. 1(b) shows the distribution of grain boundary characteristics in the material structure treated by the above method, wherein the proportion of special grain boundaries is 75% (see table 1 for process conditions), the black line in the figure represents a high-energy free grain boundary, and the gray line represents a low-energy Σ CSL grain boundary.
Claims (7)
1. A method for improving the hydrogen embrittlement resistance of 304 austenitic stainless steel is characterized by comprising the following steps:
(1) carrying out solution treatment on a 304 stainless steel plate;
(2) rapidly placing the 304 stainless steel plate subjected to solution treatment in a liquid cooling medium for cooling;
(3) placing the cooled plate in a double-roller mill, and carrying out unidirectional cold rolling;
(4) repeating the operation of the step (3), and carrying out one-way multi-pass cold rolling until the final deformation amount is 5-9%;
(5) placing the plate treated in the step (4) in a tube furnace, and annealing the plate at 1050-1100 ℃ for 5-10 min;
(6) and (4) placing the annealed plate in a liquid cooling medium for cooling.
2. The method as set forth in claim 1, wherein in the step (1), the solution treatment temperature is 1000-1100 ℃ and the solution treatment time is 25-35 min.
3. The method of claim 1, wherein in step (2), the liquid cooling medium is an ice-water mixture.
4. The method of claim 1, wherein the reduction amount of the unidirectional cold rolling in the step (3) is 0.05 to 0.15 mm.
5. The method of claim 1, wherein in step (4), the final deformation is 7%.
6. The method of claim 1, wherein in step (5), the sheet is annealed at 1075 ℃ for 7 min.
7. The method of claim 1, wherein in step (6), the liquid cooling medium is an ice-water mixture.
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Cited By (5)
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| CN114058977A (en) * | 2021-10-20 | 2022-02-18 | 中国科学院金属研究所 | MP-2-brand high-strength hydrogen embrittlement-resistant membrane and preparation method thereof |
| CN114058976A (en) * | 2021-10-20 | 2022-02-18 | 中国科学院金属研究所 | Preparation method of special plate for hydrogen-brittleness-resistant membrane of high-pressure hydrogen diaphragm compressor |
| CN115261580A (en) * | 2022-08-23 | 2022-11-01 | 华中科技大学 | Stainless steel surface grain boundary engineering treatment method based on cutting processing and product |
| CN115491480A (en) * | 2022-09-15 | 2022-12-20 | 浙江蓝能燃气设备有限公司 | Hydrogen storage bottle type container heat treatment system |
| CN116117278A (en) * | 2021-11-17 | 2023-05-16 | 华南理工大学 | Austenitic stainless steel hydrogen embrittlement-resistant weldment for hydrogen energy equipment and preparation method |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114058977A (en) * | 2021-10-20 | 2022-02-18 | 中国科学院金属研究所 | MP-2-brand high-strength hydrogen embrittlement-resistant membrane and preparation method thereof |
| CN114058976A (en) * | 2021-10-20 | 2022-02-18 | 中国科学院金属研究所 | Preparation method of special plate for hydrogen-brittleness-resistant membrane of high-pressure hydrogen diaphragm compressor |
| CN116117278A (en) * | 2021-11-17 | 2023-05-16 | 华南理工大学 | Austenitic stainless steel hydrogen embrittlement-resistant weldment for hydrogen energy equipment and preparation method |
| CN116117278B (en) * | 2021-11-17 | 2023-09-26 | 华南理工大学 | Austenitic stainless steel hydrogen embrittlement-resistant weldment for hydrogen energy equipment and preparation method |
| CN115261580A (en) * | 2022-08-23 | 2022-11-01 | 华中科技大学 | Stainless steel surface grain boundary engineering treatment method based on cutting processing and product |
| CN115491480A (en) * | 2022-09-15 | 2022-12-20 | 浙江蓝能燃气设备有限公司 | Hydrogen storage bottle type container heat treatment system |
| CN115491480B (en) * | 2022-09-15 | 2024-01-26 | 浙江蓝能氢能科技股份有限公司 | Hydrogen storage bottle type container heat treatment system |
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Application publication date: 20200605 |