CN110607490B - Hafnium zirconium titanium reinforced austenitic stainless steel and preparation method thereof - Google Patents
Hafnium zirconium titanium reinforced austenitic stainless steel and preparation method thereof Download PDFInfo
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- 229910000963 austenitic stainless steel Inorganic materials 0.000 title claims abstract description 45
- 238000002360 preparation method Methods 0.000 title claims abstract description 15
- URXDOZXTRQGRIP-UHFFFAOYSA-N [Hf].[Zr].[Ti] Chemical compound [Hf].[Zr].[Ti] URXDOZXTRQGRIP-UHFFFAOYSA-N 0.000 title claims abstract description 13
- 229910001220 stainless steel Inorganic materials 0.000 claims abstract description 42
- 239000010935 stainless steel Substances 0.000 claims abstract description 42
- 238000005266 casting Methods 0.000 claims abstract description 38
- 239000010936 titanium Substances 0.000 claims abstract description 34
- 238000005098 hot rolling Methods 0.000 claims abstract description 30
- 238000005097 cold rolling Methods 0.000 claims abstract description 23
- RTAQQCXQSZGOHL-UHFFFAOYSA-N Titanium Chemical compound [Ti] RTAQQCXQSZGOHL-UHFFFAOYSA-N 0.000 claims abstract description 21
- QCWXUUIWCKQGHC-UHFFFAOYSA-N Zirconium Chemical compound [Zr] QCWXUUIWCKQGHC-UHFFFAOYSA-N 0.000 claims abstract description 21
- 229910052719 titanium Inorganic materials 0.000 claims abstract description 21
- 229910052726 zirconium Inorganic materials 0.000 claims abstract description 21
- 238000003723 Smelting Methods 0.000 claims abstract description 20
- 238000010438 heat treatment Methods 0.000 claims abstract description 15
- 229910052735 hafnium Inorganic materials 0.000 claims abstract description 14
- VBJZVLUMGGDVMO-UHFFFAOYSA-N hafnium atom Chemical compound [Hf] VBJZVLUMGGDVMO-UHFFFAOYSA-N 0.000 claims abstract description 14
- 229910052751 metal Inorganic materials 0.000 claims description 55
- 239000002184 metal Substances 0.000 claims description 55
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 claims description 34
- XEEYBQQBJWHFJM-UHFFFAOYSA-N iron Substances [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 claims description 33
- PXHVJJICTQNCMI-UHFFFAOYSA-N nickel Substances [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 claims description 32
- 238000005096 rolling process Methods 0.000 claims description 30
- 229910008652 TiZrHf Inorganic materials 0.000 claims description 24
- 229910045601 alloy Inorganic materials 0.000 claims description 20
- 239000000956 alloy Substances 0.000 claims description 20
- 238000000137 annealing Methods 0.000 claims description 18
- 239000011651 chromium Substances 0.000 claims description 18
- 229910052786 argon Inorganic materials 0.000 claims description 17
- 238000002844 melting Methods 0.000 claims description 16
- 230000008018 melting Effects 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 16
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 claims description 14
- 239000011572 manganese Substances 0.000 claims description 14
- 230000008569 process Effects 0.000 claims description 14
- 239000000203 mixture Substances 0.000 claims description 11
- 230000009467 reduction Effects 0.000 claims description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- 238000001816 cooling Methods 0.000 claims description 9
- 238000005516 engineering process Methods 0.000 claims description 9
- 229910052742 iron Inorganic materials 0.000 claims description 9
- XWHPIFXRKKHEKR-UHFFFAOYSA-N iron silicon Chemical compound [Si].[Fe] XWHPIFXRKKHEKR-UHFFFAOYSA-N 0.000 claims description 9
- 238000003760 magnetic stirring Methods 0.000 claims description 9
- WPBNNNQJVZRUHP-UHFFFAOYSA-L manganese(2+);methyl n-[[2-(methoxycarbonylcarbamothioylamino)phenyl]carbamothioyl]carbamate;n-[2-(sulfidocarbothioylamino)ethyl]carbamodithioate Chemical compound [Mn+2].[S-]C(=S)NCCNC([S-])=S.COC(=O)NC(=S)NC1=CC=CC=C1NC(=S)NC(=O)OC WPBNNNQJVZRUHP-UHFFFAOYSA-L 0.000 claims description 9
- QMQXDJATSGGYDR-UHFFFAOYSA-N methylidyneiron Chemical compound [C].[Fe] QMQXDJATSGGYDR-UHFFFAOYSA-N 0.000 claims description 9
- 229910052759 nickel Inorganic materials 0.000 claims description 9
- 238000010791 quenching Methods 0.000 claims description 9
- 230000000171 quenching effect Effects 0.000 claims description 9
- 239000002994 raw material Substances 0.000 claims description 9
- 239000007789 gas Substances 0.000 claims description 8
- 230000006698 induction Effects 0.000 claims description 8
- 230000001681 protective effect Effects 0.000 claims description 8
- 238000005260 corrosion Methods 0.000 abstract description 48
- 230000007797 corrosion Effects 0.000 abstract description 47
- 239000003792 electrolyte Substances 0.000 abstract description 10
- 239000000243 solution Substances 0.000 description 11
- 239000010949 copper Substances 0.000 description 7
- 238000004321 preservation Methods 0.000 description 7
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 5
- 229910052804 chromium Inorganic materials 0.000 description 5
- 229910052802 copper Inorganic materials 0.000 description 5
- 230000010287 polarization Effects 0.000 description 5
- 238000012360 testing method Methods 0.000 description 5
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 description 4
- QAOWNCQODCNURD-UHFFFAOYSA-N Sulfuric acid Chemical compound OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 4
- 229910001566 austenite Inorganic materials 0.000 description 4
- 229910052799 carbon Inorganic materials 0.000 description 4
- 239000013078 crystal Substances 0.000 description 4
- 238000012545 processing Methods 0.000 description 3
- 239000006104 solid solution Substances 0.000 description 3
- 239000010963 304 stainless steel Substances 0.000 description 2
- 229910000589 SAE 304 stainless steel Inorganic materials 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 229910001567 cementite Inorganic materials 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000009826 distribution Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 238000005530 etching Methods 0.000 description 2
- 238000009776 industrial production Methods 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- BASFCYQUMIYNBI-UHFFFAOYSA-N platinum Chemical compound [Pt] BASFCYQUMIYNBI-UHFFFAOYSA-N 0.000 description 2
- 230000008092 positive effect Effects 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 239000012798 spherical particle Substances 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000010998 test method Methods 0.000 description 2
- UPTYVWMFIKKZIH-UHFFFAOYSA-N [Co].[Hf].[Cu] Chemical compound [Co].[Hf].[Cu] UPTYVWMFIKKZIH-UHFFFAOYSA-N 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- HDLKRBKBZRWMHV-UHFFFAOYSA-N copper hafnium Chemical compound [Cu].[Hf] HDLKRBKBZRWMHV-UHFFFAOYSA-N 0.000 description 1
- 238000002425 crystallisation Methods 0.000 description 1
- 230000008025 crystallization Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000007812 deficiency Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- ZOMNIUBKTOKEHS-UHFFFAOYSA-L dimercury dichloride Chemical class Cl[Hg][Hg]Cl ZOMNIUBKTOKEHS-UHFFFAOYSA-L 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 238000013213 extrapolation Methods 0.000 description 1
- 238000005242 forging Methods 0.000 description 1
- 150000002500 ions Chemical class 0.000 description 1
- KSOKAHYVTMZFBJ-UHFFFAOYSA-N iron;methane Chemical compound C.[Fe].[Fe].[Fe] KSOKAHYVTMZFBJ-UHFFFAOYSA-N 0.000 description 1
- 229910052748 manganese Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 150000001247 metal acetylides Chemical class 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 239000002245 particle Substances 0.000 description 1
- 229910052698 phosphorus Inorganic materials 0.000 description 1
- 229910052697 platinum Inorganic materials 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 238000004080 punching Methods 0.000 description 1
- 238000005215 recombination Methods 0.000 description 1
- 230000006798 recombination Effects 0.000 description 1
- 238000005204 segregation Methods 0.000 description 1
- VSZWPYCFIRKVQL-UHFFFAOYSA-N selanylidenegallium;selenium Chemical compound [Se].[Se]=[Ga].[Se]=[Ga] VSZWPYCFIRKVQL-UHFFFAOYSA-N 0.000 description 1
- 229910052710 silicon Inorganic materials 0.000 description 1
- 239000007787 solid Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
- 238000005728 strengthening Methods 0.000 description 1
- 229910052717 sulfur Inorganic materials 0.000 description 1
- 238000009864 tensile test Methods 0.000 description 1
- 238000009785 tube rolling Methods 0.000 description 1
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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
- C21D8/005—Modifying the physical properties by deformation combined with, or followed by, heat treatment of ferrous alloys
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C33/00—Making ferrous alloys
- C22C33/04—Making ferrous alloys by melting
- C22C33/06—Making ferrous alloys by melting using master alloys
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/002—Ferrous alloys, e.g. steel alloys containing In, Mg, or other elements not provided for in one single group C22C38/001 - C22C38/60
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/50—Ferrous alloys, e.g. steel alloys containing chromium with nickel with titanium or zirconium
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C38/00—Ferrous alloys, e.g. steel alloys
- C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
- C22C38/40—Ferrous alloys, e.g. steel alloys containing chromium with nickel
- C22C38/58—Ferrous alloys, e.g. steel alloys containing chromium with nickel with more than 1.5% by weight of manganese
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- Engineering & Computer Science (AREA)
- Materials Engineering (AREA)
- Mechanical Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Sheet Steel (AREA)
- Heat Treatment Of Steel (AREA)
Abstract
The invention discloses a hafnium zirconium titanium reinforced austenitic stainless steel and a preparation method thereof, and the austenitic stainless steel comprises the following elements: according to the mass percentage, C is less than or equal to 0.05, Ni is 8.0-13.0, Cr is 18.0-22.0, Ti is less than or equal to 0.1, Hf is less than or equal to 0.05 and less than or equal to 0.4, Zr is less than or equal to 0.05 and less than or equal to 0.3, Mn is less than or equal to 2.0, Si is less than or equal to 1.0, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe. The preparation method comprises the following steps: (1) smelting and casting stainless steel; (2) hot rolling and cogging; (3) cold rolling deformation; (4) and (4) high-temperature heat treatment. The stainless steel of the invention is added with zirconium, hafnium and titanium, which not only can improve the strength, but also can improve the irradiation resistance of the austenitic stainless steel, and the H content is 0.5mol/L at 80 DEG C2SO4In the electrolyte, the corrosion rate of the austenitic stainless steel is 20.3-32.7 muA/cm2Moreover, the plasticity of the austenitic stainless steel is higher than 49%, and the tensile strength is higher than 730 MPa.
Description
Technical Field
The invention relates to hafnium zirconium titanium reinforced austenitic stainless steel and a preparation method thereof, belonging to the field of austenitic stainless steel.
Background
In the face of the current increasingly severe resource, energy and environmental problems, sustainable development of energy is becoming more important. Nuclear power is one of the important sources for large-scale sustainable electric energy supply in the world today. The nuclear power plant is a new type of power plant that utilizes the energy in the nuclear power plant to generate electricity on a large scale. Nuclear power currently accounts for approximately 16% of the total world power production. The austenitic stainless steel is widely applied to the field of nuclear power with excellent corrosion resistance, but is also very easy to be corroded by corrosive ions, stress corrosion and pitting corrosion occur, and the irradiation resistance and the mechanical property of the austenitic stainless steel are sharply reduced under the irradiation condition of high dose. Therefore, the irradiation resistance, corrosion resistance and mechanical properties of austenitic stainless steel need to be stably improved in service in a reactor.
The invention patent application with publication number CN 109355590A discloses copper-hafnium corrosion-resistant reinforced austenitic stainless steel and a preparation method thereof, and austeniteThe stainless steel comprises the components of less than or equal to 0.07 of C, 8.0-10.0 of Ni, 17.0-19.0 of Cr, less than or equal to 1.04 of Hf, 0.2-0.8 of Cu, less than or equal to 2.0 of Mn, less than or equal to 1.0 of Si, less than or equal to 0.035 of P, less than or equal to 0.030 of S, and the balance of Fe; the corrosion rate of the alloy in a 0.5mol/L sulfuric acid solution at 80 ℃ is 10.8-12.5 mu A/cm2The yield strength is 300-320 MPa, the tensile strength is 590-610 MPa, and the plasticity is 41-45%.
The invention patent application of publication No. CN 109355595A discloses a copper-hafnium-cobalt modified stainless steel and a processing and heat treatment method thereof, wherein the components of the austenitic stainless steel are that C is less than or equal to 0.03, Ni is 12.0-15.0, Cr is 16.0-18.0, Mo is 2.0-3.0, Hf is less than or equal to 0.74, Cu is 0.2-0.8, Co is 0.1-0.5, Mn is less than or equal to 2.0, Si is less than or equal to 1.0, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe; the corrosion rate of the alloy in a 0.5mol/L sulfuric acid solution at the temperature of 80 ℃ is 1.26-1.82 mu A/cm2, the yield strength is 150-160 MPa, the tensile strength is 520-540 MPa, and the plasticity is 42-47%.
Although the two technical schemes can enhance the performance of the austenitic stainless steel to a certain degree, the corrosion resistance, the mechanical property or the plasticity of the obtained austenitic stainless steel are still low; in addition, the two technical schemes both adopt copper for modification, and although copper can promote crystallization, the copper is easy to generate hot brittleness in the hot processing process, so that the mechanical property of the copper is not stable enough, and the copper is beneficial to certain extent in the industrial production process.
Disclosure of Invention
The purpose of the invention is as follows: aiming at the problems of lower irradiation resistance, corrosion resistance, mechanical property and the like of the conventional austenitic stainless steel, the invention provides a hafnium zirconium titanium reinforced austenitic stainless steel and a preparation method thereof.
The technical scheme is as follows: the invention relates to hafnium zirconium titanium reinforced austenitic stainless steel, which comprises the following elements: according to the mass percentage, C is less than or equal to 0.05, Ni is 8.0-13.0, Cr is 18.0-22.0, Ti is less than or equal to 0.1, Hf is less than or equal to 0.05 and less than or equal to 0.4, Zr is less than or equal to 0.05 and less than or equal to 0.3, Mn is less than or equal to 2.0, Si is less than or equal to 1.0, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe.
The preparation method of the hafnium zirconium titanium reinforced austenitic stainless steel comprises the following steps:
(1) selecting raw materials of pure iron, metal chromium, metal nickel, metal manganese, metal hafnium, metal titanium, metal zirconium, iron silicon and iron carbon blocks according to the mass percentage of each element in the stainless steel, smelting and casting to form an alloy ingot;
(2) hot rolling and cogging;
(3) cold rolling deformation;
(4) and (4) high-temperature heat treatment.
After the alloy is smelted, the carbide in the alloy can be fully crushed and dispersed and distributed through hot rolling cogging and cold rolling deformation, and then a uniform austenite structure can be obtained through high-temperature solution treatment, so that the alloy has high strength and corrosion resistance.
Preferably, in the step (1), the smelting and casting processes are performed in vacuum or under argon protection, and the metal solution can be uniformly mixed by using a magnetic stirring technology in the smelting process.
In the step (2), the process conditions for hot rolling and cogging are preferably as follows: heating the casting blank to 1100-1300 ℃, preserving heat for 10-24 hours, and then discharging for rolling; the starting temperature of hot rolling is more than or equal to 1050 ℃, the finishing temperature is more than or equal to 900 ℃, and the total hot rolling load of the plate is more than or equal to 40%. The pipes, rods, wires, sections, cold punching parts and cast ingots can be cogging by hot forging, hole-pattern rolling or universal rolling.
In the step (3), cold deformation can be carried out by adopting a reciprocating tube rolling, hole pattern rolling, universal rolling or drawing method so as to obtain the required size and specification of the product. Preferably, the process conditions of cold rolling deformation are as follows: the total rolling reduction of cold rolling is more than or equal to 40 percent. The large cold rolling deformation is beneficial to ensuring that a uniform structure is formed after subsequent heating treatment.
Further, in the step (4), the process conditions of the high-temperature heat treatment are as follows: after cold rolling deformation, annealing treatment is carried out at 850-1000 ℃, and the heat preservation time is 60-120 minutes; after annealing, water quenching is adopted for rapid cooling. The purpose of the high temperature hold is to form coarse recrystallized grains, so that the broken spherical carbides are transferred from the grain boundaries to the interior of the coarse recrystallized grains, thereby reducing the grain boundary corrosion tendency.
The invention principle is as follows: after the stainless steel is irradiated, a radiation-induced segregation (RIS) effect is generated, so that a chromium-poor phenomenon occurs on grain boundaries, the corrosion of the grain boundaries is poor, and stress cracking corrosion easily occurs. Zirconium and hafnium are elements with large size radius, which can effectively reduce or inhibit radiation-assisted stress corrosion cracking (IASCC), and promote defect recombination mainly through a solid solution-vacancy capture mechanism. Specifically, a strong carbide forming element Hf is added into the alloy to form a high-stability spherical particle HfC compound, so that the solid solution content of actual C in austenite particles is greatly reduced, and the corrosion resistance of the stainless steel is improved; meanwhile, titanium and zirconium are both strong carbide forming elements, and by adding titanium and zirconium into the stainless steel, carbon is combined with the titanium and the zirconium to generate TiC and ZrC, so that the carbon is not combined with chromium, and crystal boundary chromium deficiency is not caused, thereby avoiding intergranular corrosion and further improving the corrosion resistance of the stainless steel; in addition, the addition of titanium and zirconium in stainless steel can change the inclusion form and distribution in the steel, and has a certain positive effect on the mechanical properties of austenitic stainless steel.
Has the advantages that: compared with the prior art, the invention has the advantages that: (1) according to the invention, zirconium, hafnium and titanium are added into the stainless steel, so that not only can the strength be improved, but also the irradiation resistance of the austenitic stainless steel can be improved, and finally, the hafnium, zirconium and titanium reinforced austenitic stainless steel with good corrosion resistance and excellent mechanical property is obtained; 0.5mol/L H at 80 DEG C2SO4In the electrolyte, the corrosion rate of the austenitic stainless steel is 20.3-32.7 muA/cm2Moreover, the plasticity of the austenitic stainless steel is higher than 49%, and the tensile strength is higher than 730 MPa; (2) the preparation method of the austenitic stainless steel is simple, the process controllability is strong, and the industrial production is easy to realize.
Drawings
FIG. 1 is a graph showing the mechanical properties of a hafnium zirconium titanium reinforced austenitic stainless steel manufactured in example 1;
FIG. 2 is an electron microscope scanning image of the corrosion surface of the hafnium zirconium titanium reinforced austenitic stainless steel prepared in example 2 after being subjected to the corrosion resistance test;
FIG. 3 is a polarization diagram of the hafnium zirconium titanium reinforced austenitic stainless steel prepared in example 3 during a corrosion resistance test.
Detailed Description
The technical scheme of the invention is further explained by combining the attached drawings.
The invention relates to a hafnium zirconium titanium reinforced austenitic stainless steel, which is characterized in that on the basis of 304 austenitic stainless steel alloy components, strong carbide forming elements of hafnium (Hf), zirconium (Zr) and titanium (Ti) are added, and 304-TiZrHf stainless steel is used for short. The alloy comprises the following elements in percentage by mass: c is less than or equal to 0.05, Ni is 8.0-13.0, Cr is 18.0-22.0, Ti is less than or equal to 0.1, Hf is less than or equal to 0.05 and less than or equal to 0.4, Zr is less than or equal to 0.05 and less than or equal to 0.3, Mn is less than or equal to 2.0, Si is less than or equal to 1.0, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe.
304 is American grade, corresponding to Chinese stainless steel grade 06Cr19Ni10(ii) a 304 stainless steel is a food grade stainless steel accepted by the state, is mainly used in the aspects of food processing, storage and transportation, and also has important application in medical appliances, ship parts and the like. The performance indexes of the plate are as follows: the yield strength is more than or equal to 205MPa, the tensile strength is more than or equal to 520MPa, the elongation is more than or equal to 40 percent, and the hardness is less than or equal to HV 200.
The 304 stainless steel contains not more than 0.08% of C. C in austenitic stainless steel has a strong solid solution strengthening effect, but C is easily combined with Fe to form cementite Fe3C, is precipitated in a lamellar manner, so that the corrosion resistance of the stainless steel is difficult to improve. Therefore, the addition of the strong carbide forming element Hf to the alloy results in the formation of a high stability HfC compound in the form of spherical particles, which greatly reduces the actual C solid solution content in the austenite grains and improves the corrosion resistance of stainless steel.
Titanium and zirconium are both strong carbide forming elements, and when titanium and zirconium are added into stainless steel, carbon is combined with the titanium and the zirconium to generate TiC and ZrC, so that the carbon is not combined with chromium, the chromium depletion of a crystal boundary is avoided, and the intergranular corrosion is avoided. The content of chromium in the austenite grains is improved, so that the corrosion resistance of the stainless steel is increased. The titanium and zirconium added into the stainless steel can also change the inclusion form and distribution in the steel, and have a certain positive effect on the mechanical properties of the austenitic stainless steel.
Example 1
Selecting pure iron, metal chromium, metal nickel, metal manganese, metal hafnium, metal zirconium, metal titanium, iron silicon and iron carbon block as raw materials, and preparing the austenitic stainless steel with the following components: c is 0.05, Ni is 11, Cr is 20, Ti is 0.1, Hf is 0.05, Zr is 0.1, Mn is 2, Si is 1, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe.
Casting into alloy cast ingots through arc melting or induction melting; smelting is carried out in vacuum or under the protection of argon, and a magnetic stirring technology is utilized to uniformly mix the metal solution in the smelting process; casting under vacuum or argon protection to form square ingot or round ingot;
the ingot is hot-rolled and cogging by adopting a rolling mill, the hot-rolling scheme is that the casting blank is heated to 1200 +/-10 ℃, the temperature is kept for 24 hours, then the casting blank is discharged from a furnace for rolling, the hot-rolling starting temperature is 1180 +/-20 ℃, the finish rolling temperature is more than or equal to 950 ℃, and the total hot-rolling amount of the plate is more than or equal to 60 percent;
the plate is deformed by cold rolling, and the total cold rolling reduction is more than or equal to 50 percent;
annealing the plate at 950 ℃, wherein the heat preservation time is 90 minutes, and protective gas is not needed during heating; and after annealing, water quenching and cooling are adopted to obtain the 304-TiZrHf stainless steel.
The hardness of the 304-TiZrHf stainless steel is 309HV, the yield strength is 400MPa, the tensile strength is 780MPa, and the elongation is 51 percent; fig. 1 is a mechanical property curve, and it can be seen from fig. 1 that it has very good ductility and high strength. 0.5mol/L H at 80 DEG C2SO4In the electrolyte, the corrosion rate of the 304-TiZrHf stainless steel is 31.2 mu A/cm2。
Example 2
Selecting pure iron, metal chromium, metal nickel, metal manganese, metal hafnium, metal zirconium, metal titanium, iron silicon and iron carbon block as raw materials, and preparing the austenitic stainless steel with the following components: c is 0.05, Ni is 11, Cr is 20, Ti is 0.1, Hf is 0.2, Zr is 0.1, Mn is 2, Si is 1, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe.
Casting into alloy cast ingots through arc melting or induction melting; smelting is carried out in vacuum or under the protection of argon, and a magnetic stirring technology is utilized to uniformly mix the metal solution in the smelting process; casting under vacuum or argon protection to form square ingot or round ingot;
the ingot casting is hot-rolled and cogging by adopting a rolling mill, the hot-rolling scheme is that the casting blank is heated to 1250 +/-10 ℃, the temperature is kept for 10 hours, then the casting blank is discharged from a furnace for rolling, the hot-rolling starting temperature is 1240 +/-20 ℃, the final rolling temperature is more than or equal to 950 ℃, and the total hot-rolling amount of the plate is more than or equal to 60 percent;
the plate is deformed by cold rolling, and the total cold rolling reduction is more than or equal to 50 percent;
annealing the plate at 950 ℃, wherein the heat preservation time is 90 minutes, and protective gas is not needed during heating; and after annealing, water quenching and cooling are adopted to obtain the 304-TiZrHf stainless steel.
The hardness of the 304-TiZrHf stainless steel is 316HV, the yield strength is 387MPa, the tensile strength is 760MPa, and the elongation is 49%. 0.5mol/L H at 80 DEG C2SO4In the electrolyte, the corrosion rate of the 304-TiZrHf stainless steel is 25.1 mu A/cm2(ii) a FIG. 2 shows the metallographic phase of the corroded surface of the alloy after a corrosion resistance test, and H is 0.5mol/L at 80 DEG C2SO4And (3) corroding in the electrolyte for 30min, wherein the corroded surface is smooth, crystal grains are very fine and uniform, a small amount of corrosion products exist, the crystal boundary is very clear, and the corrosion resistance is strong.
Example 3
Selecting pure iron, metal chromium, metal nickel, metal manganese, metal hafnium, metal zirconium, metal titanium, iron silicon and iron carbon block as raw materials, and preparing the austenitic stainless steel with the following components: c is 0.05, Ni is 11, Cr is 20, Ti is 0.1, Hf is 0.4, Zr is 0.1, Mn is 2, Si is 1, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe.
Casting into alloy cast ingots through arc melting or induction melting; smelting is carried out in vacuum or under the protection of argon, and a magnetic stirring technology is utilized to uniformly mix the metal solution in the smelting process; casting under vacuum or argon protection to form square ingot or round ingot;
the ingot is hot-rolled and cogging by adopting a rolling mill, the hot-rolling scheme is that the casting blank is heated to 1150 +/-10 ℃, the temperature is kept for 24 hours, then the casting blank is discharged from a furnace for rolling, the hot-rolling starting temperature is 1140 +/-20 ℃, the final rolling temperature is more than or equal to 950 ℃, and the total hot-rolling amount of the plate is more than or equal to 60 percent;
the plate is deformed by cold rolling, and the total cold rolling reduction is more than or equal to 50 percent;
annealing the plate at 950 ℃, wherein the heat preservation time is 90 minutes, and protective gas is not needed during heating; and after annealing, water quenching and cooling are adopted to obtain the 304-TiZrHf stainless steel.
The hardness of the 304-TiZrHf stainless steel is 301HV, the yield strength is 358MPa, the tensile strength is 737MPa, and the elongation is 55 percent; FIG. 3 is a polarization curve of the cathode region on the side of the anode region, the cathode region on the right side, and the lowest point corresponding to the self-etching potential. 0.5mol/L H at 80 DEG C2SO4The corrosion rate of the 316-TiZrHf alloy in the electrolyte is 20.3 mu A/cm2。
Example 4
The preparation method selects pure iron, metal chromium, metal nickel, metal manganese, metal hafnium, metal zirconium, metal titanium, iron silicon and iron carbon block as raw materials, and the prepared austenitic stainless steel comprises the following components: c is 0.05, Ni is 11, Cr is 20, Ti is 0.1, Hf is 0.05, Zr is 0.05, Mn is 2, Si is 1, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe.
Casting into alloy cast ingots through arc melting or induction melting; smelting is carried out in vacuum or under the protection of argon, and a magnetic stirring technology is utilized to uniformly mix the metal solution in the smelting process; casting under vacuum or argon protection to form square ingot or round ingot;
the ingot is hot-rolled and cogging by adopting a rolling mill, the hot-rolling scheme is that the casting blank is heated to 1250 +/-10 ℃, the temperature is kept for 24 hours and then the casting blank is discharged from a furnace for rolling, the hot-rolling starting temperature is 1240 +/-20 ℃, the finish rolling temperature is more than or equal to 950 ℃, and the total hot-rolling amount of the plate is more than or equal to 60 percent;
the plate is deformed by cold rolling, and the total cold rolling reduction is more than or equal to 50 percent;
annealing the plate at 950 ℃, wherein the heat preservation time is 90 minutes, and protective gas is not needed during heating; and after annealing, water quenching and cooling are adopted to obtain the 304-TiZrHf stainless steel.
The hardness of the 304-TiZrHf stainless steel is 308.4HV, the yield strength is 389MPa, the tensile strength is 764MPa, and the elongation is 50%. 0.5mol/L H at 80 DEG C2SO4Corrosion of the 304-TiZrHf stainless steel in electrolyteThe etching rate is 31.6 muA/cm2。
Example 5
The preparation method selects pure iron, metal chromium, metal nickel, metal manganese, metal hafnium, metal zirconium, metal titanium, iron silicon and iron carbon block as raw materials, and the prepared austenitic stainless steel comprises the following components: c is 0.05, Ni is 11, Cr is 20, Ti is 0.1, Hf is 0.3, Zr is 0.3, Mn is 2, Si is 1, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe.
Casting into alloy cast ingots through arc melting or induction melting; smelting is carried out in vacuum or under the protection of argon, and a magnetic stirring technology is utilized to uniformly mix the metal solution in the smelting process; casting under vacuum or argon protection to form square ingot or round ingot;
the ingot is hot-rolled and cogging by adopting a rolling mill, the hot-rolling scheme is that the casting blank is heated to 1200 +/-10 ℃, the temperature is kept for 24 hours, then the casting blank is discharged from a furnace for rolling, the hot-rolling starting temperature is 1180 +/-20 ℃, the finish rolling temperature is more than or equal to 950 ℃, and the total hot-rolling amount of the plate is more than or equal to 60 percent;
the plate is deformed by cold rolling, and the total cold rolling reduction is more than or equal to 50 percent;
annealing the plate at 950 ℃, wherein the heat preservation time is 90 minutes, and protective gas is not needed during heating; and after annealing, water quenching and cooling are adopted to obtain the 304-TiZrHf stainless steel.
The hardness of the 304-TiZrHf stainless steel is 302.6HV, the yield strength is 360MPa, the tensile strength is 745MPa, and the elongation is 50%. 0.5mol/L H at 80 DEG C2SO4In the electrolyte, the corrosion rate of the 304-TiZrHf stainless steel is 22.4 mu A/cm2。
Example 6
The preparation method selects pure iron, metal chromium, metal nickel, metal manganese, metal hafnium, metal zirconium, metal titanium, iron silicon and iron carbon block as raw materials, and the prepared austenitic stainless steel comprises the following components: c is 0.03, Ni is 8, Cr is 18, Ti is 0.08, Hf is 0.05, Zr is 0.05, Mn is 1.5, Si is 0.8, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe.
Casting into alloy cast ingots through arc melting or induction melting; smelting is carried out in vacuum or under the protection of argon, and a magnetic stirring technology is utilized to uniformly mix the metal solution in the smelting process; casting under vacuum or argon protection to form square ingot or round ingot;
the ingot is hot-rolled and cogging by adopting a rolling mill, the hot-rolling scheme is that the casting blank is heated to 1150 +/-10 ℃, the temperature is kept for 10 hours, then the casting blank is discharged from a furnace for rolling, the hot-rolling starting temperature is 1140 +/-20 ℃, the final rolling temperature is more than or equal to 950 ℃, and the total hot-rolling amount of the plate is more than or equal to 40 percent;
the plate is deformed by cold rolling, and the total cold rolling reduction is more than or equal to 40 percent;
annealing the plate at 850 ℃, wherein the heat preservation time is 120 minutes, and protective gas is not needed during heating; and after annealing, water quenching and cooling are adopted to obtain the 304-TiZrHf stainless steel.
The hardness of the 304-TiZrHf stainless steel is 304.2HV, the yield strength is 354MPa, the tensile strength is 730MPa, and the elongation is 59%. 0.5mol/L H at 80 DEG C2SO4In the electrolyte, the corrosion rate of the 304-TiZrHf stainless steel is 32.7 mu A/cm2。
Example 7
The preparation method selects pure iron, metal chromium, metal nickel, metal manganese, metal hafnium, metal zirconium, metal titanium, iron silicon and iron carbon block as raw materials, and the prepared austenitic stainless steel comprises the following components: c is 0.05, Ni is 13, Cr is 20, Ti is 0.1, Hf is 0.3, Zr is 0.3, Mn is 2, Si is 1, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe.
Casting into alloy cast ingots through arc melting or induction melting; smelting is carried out in vacuum or under the protection of argon, and a magnetic stirring technology is utilized to uniformly mix the metal solution in the smelting process; casting under vacuum or argon protection to form square ingot or round ingot;
the ingot is hot-rolled and cogging by adopting a rolling mill, the hot-rolling scheme is that the casting blank is heated to 1200 +/-10 ℃, the temperature is kept for 24 hours, then the casting blank is discharged from a furnace for rolling, the hot-rolling starting temperature is 1180 +/-20 ℃, the finish rolling temperature is more than or equal to 950 ℃, and the total hot-rolling amount of the plate is more than or equal to 60 percent;
the plate is deformed by cold rolling, and the total cold rolling reduction is more than or equal to 50 percent;
annealing the plate at 1000 ℃ for 60 minutes without using protective gas during heating; and after annealing, water quenching and cooling are adopted to obtain the 304-TiZrHf stainless steel.
The hardness of the 304-TiZrHf stainless steel is 314.3HV, the yield strength is 394MPa, the tensile strength is 775MPa, and the elongation is 49%. 0.5mol/L H at 80 DEG C2SO4In the electrolyte, the corrosion rate of the 304-TiZrHf stainless steel is 21.2 mu A/cm2。
The test methods for the corrosion resistance, hardness and tensile mechanical properties of the 304-TiZrHf stainless steel in the above examples are as follows.
(1) Hardness: the hardness test was carried out using an HVS-50 Vickers hardness tester with a load of 1Kg, and 5 points were hit and averaged, as shown in Table 1.
(2) Tensile mechanical properties: an electronic universal tester is adopted for carrying out a tensile test, a rectangular sample with the nominal section size of 2-3 multiplied by 4 multiplied by 20.6mm is taken, and the average values of the tensile strength, the yield strength and the elongation of 3 samples treated in the same way are listed in table 1.
(3) Corrosion resistance
The corrosion current was obtained by Tafel (Tafel) line extrapolation. The test method is that a metal sample is made into an electrode and is immersed into a corrosive medium, steady volt-ampere (E-I) data is measured, a log I-E diagram is made, and the straight line part of a cathode polarization curve and an anode polarization curve is prolonged; the obtained intersection point is corresponding to logIcor, and the corrosion current Icor is divided by the sample area S accurately measured in advance0Thus obtaining the corrosion rate.
Comparison of corrosion performance was performed using the electrochemical workstation CHI660E at 80 ℃ as test temperature. The specific measurement conditions of the corrosion rate are: the area of the corroded surface is 1cm2The stainless steel is taken as a working electrode, a saturated calomel electrode is taken as a reference electrode, and a platinum sheet is taken as an auxiliary electrode; 0.5mol/L of H2SO4Heating the electrolyte to 80 ℃ by using a water bath box; the samples were subjected to a linear potential scan at a scan rate of 2 mV/s. The measurement is completed by the potentiostat function of an electrochemical potentiostat or an electrochemical workstation, the measured polarization curve is subjected to Tafel (Tafel) fitting by using the test software of the instrument to obtain the corrosion current, and the corrosion current Icor is divided by the sample area S accurately measured in advance0The resulting corrosion rate was measured 3 times and averaged, as shown in table 1.
TABLE 1 compositions and Corrosion rates, hardness and tensile Properties of the examples
Note: the contents of Mn, Si, P, S, and the like in the examples in table 1 correspond to the elemental composition of austenitic stainless steel, and Fe is the balance and is not listed in table 1.
Claims (1)
1. A hafnium zirconium titanium reinforced austenitic stainless steel, characterized by, the elemental composition of the austenitic stainless steel is as follows: according to the mass percentage, C is 0.05, Ni is 13, Cr is 20, Ti is 0.1, Hf is 0.3, Zr is 0.3, Mn is 2, Si is 1, P is less than or equal to 0.035, S is less than or equal to 0.030, and the balance is Fe;
the preparation method of the hafnium zirconium titanium reinforced austenitic stainless steel comprises the following steps:
the preparation method selects pure iron, metal chromium, metal nickel, metal manganese, metal hafnium, metal zirconium, metal titanium, iron silicon and iron carbon block as raw materials, and the prepared austenitic stainless steel comprises the following components: c is 0.05, Ni is 13, Cr is 20, Ti is 0.1, Hf is 0.3, Zr is 0.3, Mn is 2, Si is 1, P is less than or equal to 0.035, S is less than or equal to 0.030, and Fe is the rest;
casting into alloy cast ingots through arc melting or induction melting; smelting is carried out in vacuum or under the protection of argon, and a magnetic stirring technology is utilized to uniformly mix the metal solution in the smelting process; casting under vacuum or argon protection to form square ingot or round ingot;
the ingot casting is hot-rolled and cogging by adopting a rolling mill, the hot-rolling scheme is that the casting blank is heated to 1200 +/-10 ℃, the temperature is kept for 24 hours, then the casting blank is discharged from a furnace for rolling, the hot-rolling starting temperature is 1180 +/-20 ℃, the finish rolling temperature is more than or equal to 950 ℃, and the hot-rolling total reduction of the plate is more than or equal to 60%;
the plate is deformed by cold rolling, and the total cold rolling reduction is more than or equal to 50 percent;
annealing the plate at 1000 ℃ for 60 minutes without using protective gas during heating; and after annealing, water quenching and cooling are adopted to obtain the 304-TiZrHf stainless steel.
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