CN114959223A - Method for optimizing performance of duplex stainless steel - Google Patents

Method for optimizing performance of duplex stainless steel Download PDF

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CN114959223A
CN114959223A CN202210745893.7A CN202210745893A CN114959223A CN 114959223 A CN114959223 A CN 114959223A CN 202210745893 A CN202210745893 A CN 202210745893A CN 114959223 A CN114959223 A CN 114959223A
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stainless steel
duplex stainless
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solid solution
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CN114959223B (en
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杨银辉
高志新
高梓豪
夏高令
袁涛
雷子漪
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Kunming University of Science and Technology
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    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
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    • C21D8/02Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
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    • C21DMODIFYING 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
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    • C21DMODIFYING 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
    • C21D1/00General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/34Methods of heating
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    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D8/00Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0221Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the working steps
    • C21D8/0226Hot rolling
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    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D8/00Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D8/00Modifying the physical properties by deformation combined with, or followed by, heat treatment
    • C21D8/02Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips
    • C21D8/0247Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment
    • C21D8/0263Modifying the physical properties by deformation combined with, or followed by, heat treatment during manufacturing of plates or strips characterised by the heat treatment following hot rolling
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    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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    • C22C33/00Making ferrous alloys
    • C22C33/04Making ferrous alloys by melting
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    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/001Ferrous alloys, e.g. steel alloys containing N
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    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22CALLOYS
    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/02Ferrous alloys, e.g. steel alloys containing silicon
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    • C22C38/04Ferrous alloys, e.g. steel alloys containing manganese
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    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/42Ferrous alloys, e.g. steel alloys containing chromium with nickel with copper
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    • C22METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
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    • C22C38/00Ferrous alloys, e.g. steel alloys
    • C22C38/18Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/40Ferrous alloys, e.g. steel alloys containing chromium with nickel
    • C22C38/44Ferrous alloys, e.g. steel alloys containing chromium with nickel with molybdenum or tungsten
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
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Abstract

The invention discloses a method for optimizing the performance of duplex stainless steel, and belongs to the technical field of duplex stainless steel materials. The method of the invention obtains the manganese-substituted-nickel-saving duplex stainless steel with the best performance by designing chemical components of the duplex stainless steel and combining with the solid solution treatment; the duplex stainless steel comprises the following chemical components in percentage by mass: c:0.01 to 0.03 percent; si: 0.03-0.05%; mn: 8% -10%; p: 0.005-0.007%; cr: 20% -22%; ni: 0.4% -0.7%; mo: 0.9 to 1.2 percent; cu: 0.2 to 0.4 percent; n: 0.15 to 0.3 percent; the balance of iron element and inevitable impurities; and carrying out solution treatment on the duplex stainless steel plate, and then carrying out water cooling at normal temperature to obtain the high-manganese ultralow-nickel duplex stainless steel material. The high-manganese ultralow-nickel duplex stainless steel material prepared by the method is obviously superior to 2205 duplex stainless steel and other duplex steels with manganese contents in the aspect of mechanical property, is close to the 2205 duplex stainless steel in the aspect of pitting corrosion resistance, and can be applied to the fields of food industry, chemical treatment containers, construction reinforcing steel bars and other structural materials.

Description

Method for optimizing performance of duplex stainless steel
Technical Field
The invention relates to a method for optimizing the performance of duplex stainless steel, and belongs to the technical field of duplex stainless steel materials.
Background
The Duplex Stainless Steel (DSS) has a ferrite and austenite two-phase structure, has high strength and good chloride corrosion resistance of the ferrite stainless steel, and excellent toughness and weldability of the austenite stainless steel, has been widely used in the fields of petrochemical industry, paper making, marine engineering, food manufacturing, nuclear power, marine engineering, construction, and the like, and has been continuously expanded in other application fields. At present, the price of Ni is continuously rising and is 10-11 times of that of Mn under the same weight.
The publication No. CN101693984A discloses a resource-saving type austenitic stainless steel with high chromium, low nickel and high Mn-N content and a preparation method thereof, the duplex stainless steel disclosed by the patent is added with a certain content of N element on the basis of the traditional duplex stainless steel, the cold processing performance and the corrosion resistance are improved, but the invention does not relate to the optimization of the heat treatment process, the Ni content is about 1 percent, and the cost is relatively high.
The invention provides a high-manganese ultralow-nickel duplex stainless steel which is obtained by replacing most of Ni with high Mn content and is subjected to solid solution optimization process treatment, so that the application of the duplex stainless steel in a severe environment is further improved while the low cost is kept, and the high-manganese ultralow-nickel duplex stainless steel has very important economic and application values.
Disclosure of Invention
The invention aims to provide a method for optimizing the performance of duplex stainless steel, which finally obtains the duplex stainless steel with excellent performance, and the duplex stainless steel with best performance is obtained by designing chemical components of the duplex stainless steel and combining with solid solution treatment; the duplex stainless steel comprises the following chemical components in percentage by mass: c:0.01 to 0.03 percent; si: 0.03-0.05%; mn: 8% -10%; p: 0.005-0.007%; cr: 20% -22%; ni: 0.4 to 0.7 percent; mo: 0.9 to 1.2 percent; cu: 0.2 to 0.4 percent; n: 0.15 to 0.3 percent; the balance being iron and unavoidable impurities.
And (3) carrying out solution treatment on the duplex stainless steel plate, and then cooling the duplex stainless steel plate by water at normal temperature.
When the solution treatment conditions are as follows: the best plasticity performance is obtained at 1080-1120 ℃ for 50-70min and the heating rate of 10-12 ℃/min.
When the solution treatment conditions are as follows: the best toughness is obtained at 1030 ℃ and 1070 ℃ and 100 ℃ and 130 min.
When the solution treatment conditions are as follows: at 980 and 1020 ℃, 50-70min, the heating rate is 10-13 ℃/min, and the best pitting corrosion resistance is obtained.
When the solution treatment conditions are as follows: the best intergranular corrosion resistance is obtained at 1030-1070 ℃ for 50-70min and the heating rate of 10-12 ℃/min.
When the solution treatment conditions are as follows: the best mechanical property and corrosion resistance can be obtained at the temperature of 980 ℃ and 1030 ℃ for 50-80min and the heating rate of 10-12 ℃/min.
Preferably, the impurities in the invention are Ca and S, wherein the content of Ca is less than or equal to 0.01 percent by mass and the content of S is less than or equal to 0.005 percent by mass in the duplex stainless steel.
Furthermore, in order to avoid the formation of sigma brittle phase in the process of solution treatment and keep the minimum content of two phases higher than 30%, the solid solution temperature interval without precipitated phase obtained by thermodynamic calculation of precipitated phase of Thermo-Calc software is larger than 950 ℃ and less than or equal to 1250 ℃.
Preferably, the preparation method of the duplex stainless steel plate specifically comprises the following steps:
(1) smelting in a vacuum smelting furnace according to the component proportion to obtain the ultralow Ni type duplex stainless steel ingot.
(2) And (3) forging the cast ingot obtained in the step (1) into a plate blank, and quickly cooling after forging.
(3) And (3) homogenizing the plate blank obtained in the step (2), and then quenching and cooling.
(4) And (4) carrying out hot rolling deformation on the plate blank obtained in the step (3), and carrying out water quenching on the hot rolled steel plate to obtain the high-Mn ultralow-Ni duplex stainless steel plate.
Preferably, the forging treatment conditions in step (2) of the present invention are: starting forging at 950-1200 ℃, wherein the forging ratio is 3-4, the finish forging temperature is more than or equal to 980 ℃, and cooling after forging.
Preferably, the tissue homogenization treatment in step (3) of the present invention is performed at a temperature of 1100 + -20 deg.C for 100-.
Preferably, the initial rolling temperature in the hot rolling deformation process in the step (4) of the invention is 970- & lt- & gt 1180 ℃, and the final rolling temperature is not lower than 960 ℃.
In the design of the ultra-low nickel type duplex stainless steel of the invention: a small amount of Ca is added to improve the distribution of oxide inclusions so as to improve the mechanical property, and excessive Ca is easy to form calcium sulfide with sulfur and is not beneficial to the corrosion resistance; mn is an element which is low in cost and can stabilize austenite, and the reason why Mn affects pitting corrosion performance is the formation of MnS to obtain a good corrosion resistant structure, so that the addition of S needs to be controlled to be less than 0.005%.
Mn is used as a common austenitizing element and can be used for replacing expensive Ni to stabilize austenite, the addition of Mn can promote the solubility increase of nitrogen in stainless steel, improve the austenite stability, change the proportion of two phases, promote solid solution strengthening and change the distribution of other alloy elements in the two phases, thereby influencing the mechanical property and the corrosion resistance. The solid solution treatment temperature determines the proportion of two phases of austenite and ferrite in the duplex stainless steel, and can also influence the distribution and solid solubility of elements such as Cr, Mn, Mo, N and the like in the duplex stainless steel, the solid solution time has important effects on the homogenization of alloy elements in the two phases and the improvement of element segregation, and the changes can have great influence on the phase change behavior, the mechanical property and the corrosion resistance of the duplex stainless steel.
The invention has the beneficial effects that:
(1) through solution treatment of the duplex stainless steel, the elongation after fracture of the sample shows a growing trend along with the increase of the solution temperature and the solution time; the solid solution temperature reaches the optimal value when the solid solution time is 1h at 1100 ℃, so the optimal solid solution treatment mode is that the solid solution temperature is 1080-1120 ℃, the temperature is 50-70min, and the temperature rise rate is 10-12 ℃/min.
(2) Through solution treatment of the duplex stainless steel, the pitting potential of the sample shows a rising trend along with the lengthening of the solution temperature and the solution time; the solid solution temperature reaches the optimal value when the solid solution time is 1h at 1000 ℃, so the optimal solid solution treatment mode is that the solid solution temperature is 980-1020 ℃, the solid solution time is 50-70min, and the temperature rise rate is 10-12 ℃/min.
(3) Through solution treatment of the duplex stainless steel, along with the increase of the solution temperature, the impact toughness of the sample shows a trend of increasing along with the increase of the solution temperature and the solution time; the solid solution temperature reaches the best when the solid solution time is 2h at 1050 ℃, so the best solid solution treatment is carried out at 1030 ℃ and 1070 ℃ for 100 ℃ and 130min, and the temperature rise rate is 10-12 ℃/min.
(4) Through solution treatment of the duplex stainless steel, with the increase of the solution temperature, the intercrystalline corrosion sensitivity value of the sample shows a trend of increasing first and then decreasing with the increase of the solution temperature and the solution time. The solid solution temperature reaches the best when the solid solution time is 1h at 1050 ℃, so the best solid solution treatment is carried out at 1030 ℃ and 1070 ℃ for 50-70min, and the temperature rise rate is 10-12 ℃/min.
In conclusion, through solution treatment at 980-1030 ℃ for 50-80min, the heating rate is 10-12 ℃/min, then quenching and cooling are carried out, the elongation after fracture exceeds 48%, the impact toughness exceeds 268J, the tensile strength exceeds 725MPa, the pitting potential exceeds 760mV, and the intercrystalline sensitivity value is lower than 30%, so that the optimal mechanical property and corrosion resistance are obtained. Compared with the existing 2205 duplex stainless steel, the content of Ni and Mo in the steel is very low, and the Ni cost is 10-11 times higher than that of Mn per ton, but the steel is far better than the 2205 duplex stainless steel and two high manganese steels in the aspect of mechanics, and is close to the 2205 duplex stainless steel in the aspect of pitting corrosion resistance, so that the steel can be applied to the fields of structural materials such as food industry, chemical treatment containers, construction reinforcing steel bars and the like.
Drawings
FIG. 1 is a two-phase equilibrium phase diagram of the solid solution temperature without precipitated phase obtained from Thermo-Calc software by thermodynamic calculation of precipitated phase in example 1.
FIG. 2 is a graph of impact toughness, elongation after fracture, and tensile strength for various solution temperatures and times for example 1.
FIG. 3 is a plot of cyclic voltammetric polarization measurements for example 1 at different solution temperatures and times.
FIG. 4 is a graph comparing the dual-ring electrochemical potentiodynamic reactivation test curve and the intercrystalline sensitivity values of example 1 at different solution temperatures and times.
FIG. 5 is a two-phase equilibrium phase diagram of the solid solution temperature without precipitated phase obtained from Thermo-Calc software by the thermodynamic calculation of precipitated phase in example 2.
FIG. 6 is a dual ring electrochemical potentiodynamic reactivation test curve for example 2 at different solution temperatures.
FIG. 7 is a two-phase equilibrium phase diagram of the solid solution temperature without precipitated phase obtained from Thermo-Calc software by the thermodynamic calculation of precipitated phase in example 3.
FIG. 8 is a graph showing impact toughness, elongation after fracture and tensile strength at different solution temperatures and solution times in example 3.
FIG. 9 is a plot of cyclic voltammetry polarization measurements for example 3 at different solutionizing temperatures and times.
FIG. 10 is a graph comparing the dual-ring electrochemical potentiodynamic reactivation test curve and the intercrystalline sensitivity values at different solution temperatures and times for example 3.
FIG. 11 is a two-phase equilibrium phase diagram of the solid solution temperature without precipitated phase obtained from Thermo-Calc software by the thermodynamic calculation of precipitated phase in example 4.
FIG. 12 is a dual ring electrochemical potentiodynamic reactivation test curve for example 4 at different solvus temperatures.
Detailed Description
The invention will be described in more detail with reference to the following figures and examples, but the scope of the invention is not limited thereto.
In the embodiment of the invention, the production cost is reduced by replacing Ni with Mn, the Mn is subjected to solution treatment at 950, 1000, 1050, 1100 and 1150 ℃, the solution treatment time is 0.5-5h, and the solution treatment is carried out in a box-type resistance furnace. After the solution treatment, the sample is pre-ground, finely ground, polished and corroded to prepare a metallographic sample, concentrated nitric acid is used for electro-corrosion, and then the metallographic structure of the sample is observed under an optical microscope. Carrying out normal-temperature tensile tests on samples with different solution treatment temperatures on an ETM205D tensile testing machine; the impact test is carried out on a JBN-300 impact testing machine, and a V-shaped notch test sample is adopted; the pitting corrosion test is carried out in 3.5% NaCI solution, and the intercrystalline corrosion solution is H 2 SO 4 NaCl and KSCN as 1.2:1.1:0.01 molar ratio (1000mL H) 2 O、54.35mL H 2 SO 4 29.25g NaCl and 0.97g KSCN) in a Chi604e electrochemical workstation.
Example 1
The stainless steel casting blank comprises the following chemical components in percentage by mass: 0.016% of C, Si: 0.038%, Mn: 8.398%, S: 0.0053%, P: 0.0071%, Cr: 21.44%, Ni: 0.5592%, Mo: 0.9142%, Cu: 0.3155%, N: 0.242%, and the balance of iron element and inevitable impurities.
(1) A stainless steel casting blank is smelted by adopting a 50kg vacuum smelting furnace.
(2) The stainless steel casting blank is pre-forged, the forging is started at 1150 ℃, the forging ratio is 3, the finish forging temperature is 980 ℃, the stainless steel casting blank is forged into a plate blank with the width of 130mm and the thickness of 30mm, and the stainless steel casting blank is rapidly cooled after being forged.
(3) Then, pre-rolling treatment is carried out, the initial rolling temperature is set to be 1120 ℃, the final rolling temperature is 980 ℃, and the plate is obtained through water quenching.
(4) In order to avoid the formation of sigma brittle phase in the process of solid solution treatment, the solid solution temperature interval without precipitated phase obtained by thermodynamic calculation of precipitated phase of Thermo-Calc software is 1000-1100 ℃, wherein the equilibrium point of two phases is 1050 ℃, and a diagram of two-phase equilibrium phase is collated in figure 1.
(5) And (4) carrying out solid solution treatment on the plate obtained in the step (3) under the conditions of 1000 ℃, 1050 ℃ and 1100 ℃ for 0.5h, 1h, 1.5h, 2h and 5h respectively, wherein the heating rate is 10 ℃/min, and then quenching and cooling.
(6) Respectively processing the samples subjected to the solution treatment in the step (5) into
Figure BDA0003719342840000051
And 10mm by 55mm impact specimens; the experimental data obtained are shown in FIG. 2.
And (4) cutting the sample impacted in the step (6) into a cuboid with the thickness of 10 mm-30 mm, and then carrying out sealing insulation treatment on the non-working surface of the sample to prepare for the pitting corrosion and intergranular corrosion experiments.
Preparing a pitting solution and an intercrystalline corrosion solution, wherein the pitting solution is a 3.5 wt% NaCl solution (1000 mLH) 2 Prepared by O and 35g NaCl) is H 2 SO 4 NaCl and KSCN as 1.2:1.1:0.01 molar ratio (1000mL H) 2 O、54.35mL H 2 SO 4 29.25g NaCl, 0.97g KSCN). And testing the pitting corrosion performance and the intergranular corrosion performance at different solid solution temperatures by using a cyclic voltammetric potentiodynamic polarization curve and a double-ring potentiodynamic reactivation method (DLEPR). FIG. 3 is a potential polarization curve of cyclic voltammetry polarization test curves at different solid solution temperatures and times, and the fitted electrochemical parameters are summarized in Table 1; FIG. 4 is a graph comparing the test curve and the intercrystalline sensitivity value of the double-ring electrochemical potentiodynamic reactivation method of the experimental steel under different solid solution temperatures and times.
TABLE 1
Solid solution temperature E coor /V I corr /A cm -2 E b /V E b -E coor
1000℃-0.5h -0.273 1.20*10 -7 0.473 0.746
1050℃-0.5h -0.281 3.48*10 -8 0.480 0.761
1100℃-0.5h -0.357 9.54*10 -7 0.433 0.790
1000℃-1h -0.297 9.84*10 -8 0.763 1.06
1050℃-1h -0.349 1.23*10 -7 0.439 0.788
1100℃-1h -0.299 8.60*10 -8 0.760 1.059
1000℃-1.5h -0.335 6.56*10 -7 0.398 0.733
1050℃-1.5h -0.582 7.32*10 -7 0.082 0.664
1100℃-1.5h -0.474 8.87*10 -6 0.132 0.603
1000℃-2h -0.384 1.38*10 -6 0.281 0.665
1050℃-2h -0.288 8.66*10 -8 0.451 0.739
1100℃-2h -0.307 1.92*10 -7 0.450 0.757
As can be seen from FIG. 2, the impact toughness of the stainless steel generally shows a tendency of increasing and then decreasing, when the solid solution temperature is 1050 ℃ and the solid solution time is 2h, the impact toughness is up to 278J, the tensile strength is also up to 726MPa, and the stainless steel generally shows good mechanical properties. As can be seen from FIG. 2, when the solution temperature is 1100 ℃ and the solution time is 1h, the elongation after fracture of the experimental steel is as high as 50.5%, which indicates that the experimental steel has excellent plasticity under the conditions; pitting potential (E) b ) The pitting corrosion resistance of the stainless steel can be tested, and the larger the pitting potential is, the more excellent the pitting corrosion resistance of the stainless steel is; as can be seen from Table 1, when the solid solution temperature is 1000 ℃ and the solid solution time is 1h, the pitting potential of the stainless steel is the highest and reaches 763 mV; it can also be seen from FIG. 3 that the polarization plateau of stainless steel is long at a solution temperature of 1000 ℃ for a solution time of 1h, which is consistent with the results obtained for pitting potentials; FIG. 4 is a diagram comparing the test curve of the double-ring electrochemical potentiodynamic reactivation method and the intercrystalline sensitivity value under different solid solution temperatures and times; as can be seen from FIG. 5, the intercrystalline sensitivity value shows a decreasing trend with the increase of the solid solution temperature, and when the solid solution temperature is 1050 ℃ and the solid solution time is 1h, the intercrystalline sensitivity value of the experimental steel reaches 14%, which indicates that under the condition, the experimental steel has good intercrystalline corrosion resistance.
Example 2
The stainless steel casting blank comprises the following chemical components in percentage by mass: c: 0.0382%, Si: 0.292%, Mn: 15.075%, S: 0.0036%, P: 0.0053%, Cr: 22.96%, Ni: 1.32%, Mo: 2.29%, Cu: 0.204%, N: 0.28%, and the balance of iron and inevitable impurities.
(1) A stainless steel cast ingot was produced by melting in a vacuum melting furnace of 50 kg.
(2) The stainless steel casting blank is pre-forged, the forging is started at 950 ℃, the forging ratio is 3, the finish forging temperature is 980 ℃, the stainless steel casting blank is forged into a plate blank with the width of 130mm and the thickness of 30mm, and the stainless steel casting blank is rapidly cooled after being forged.
(3) And (3) carrying out pre-rolling treatment, setting the initial rolling temperature to be 1020 ℃, setting the final rolling temperature to be 980 ℃, and carrying out water quenching to obtain the plate.
(4) In order to avoid the formation of sigma brittle phase in the process of solid solution treatment, the solid solution temperature interval without precipitated phase obtained by thermodynamic calculation of precipitated phase of Thermo-Calc software is 950-1050 ℃, wherein the equilibrium point of two phases is 1000 ℃, and the equilibrium phase diagram of two phases is arranged in figure 5.
(5) And (4) carrying out solid solution treatment on the plate obtained in the step (3) under the conditions of 950 ℃, 1000 ℃ and 1050 ℃ for 30min respectively, wherein the heating rate is 11 ℃/min, and then carrying out quenching cooling.
(6) Respectively processing the samples subjected to the solution treatment in the step (5) into
Figure BDA0003719342840000071
And 10mm by 55mm impact specimens; tensile strength and impact toughness are collated in Table 2.
And (4) cutting the sample impacted in the step (6) into a cuboid with the thickness of 10 mm-30 mm, and then carrying out sealing insulation treatment on the non-working surface of the sample to prepare for the pitting corrosion and intergranular corrosion experiments.
Preparing a pitting solution and an intercrystalline corrosion solution, wherein the pitting solution is a 3.5 wt% NaCl solution (1000 mLH) 2 Prepared by O and 35g NaCl) is H 2 SO 4 NaCl and KSCN in a molar ratio of 1.2:1.1:0.01 (1000mL H) 2 O、54.35mL H 2 SO 4 29.25g of NaCl and 0.97g of KSCN); testing pitting corrosion performance and intergranular corrosion performance at different solid solution temperatures by using a cyclic voltammetric potentiodynamic polarization curve and a double-ring potentiodynamic reactivation method (DLEPR); the electrochemical parameters of the potential polarization curve fitting are summarized in Table 3, and FIG. 6 is a test curve of the double-ring electrochemical potentiodynamic reactivation method at different solid solution temperaturesTable 4 shows the intercrystalline sensitivity values at different solid solution temperatures.
TABLE 2
Solid solution temperature 950 1000℃ 1050℃
Elongation after Break (%) 34.5 35 37
Tensile strength (MPa) 748 750 763
Impact toughness (MPa) 2.2 258.8 149
TABLE 3
Solid solution temperature E coor /V I corr (A cm -2 ) E b /V E b -E coor
950℃-0.5h -0.508 4.906*10 -8 0.215 0.723
1000℃-0.5h -0.317 1.064*10 -7 0.731 1.490
1050℃-0.5h -0.465 3.826*10 -7 0.916 1.372
TABLE 4
Solid solution temperature 950 1000℃ 1050℃
Ra 0.17 0.15 0.056
Table 2 shows that the elongation after fracture and the tensile strength of the stainless steel both show a trend of increasing, but the impact toughness of the stainless steel shows a trend of decreasing with the increase of the solid solution temperature, and when the solid solution temperature is 1050 ℃ and the solid solution time is 0.5h, the elongation after fracture reaches 37%, which indicates that the experimental steel has good plasticity under the conditions. When the solid solution temperature is 1000 ℃ and the solid solution time is 0.5h, the impact toughness and the tensile strength of the experimental steel are optimal, which shows that the experimental steel has good mechanical properties under the condition. However, the experimental steel of example 1 is superior to the experimental steel of example 2 in both plasticity and comprehensive mechanical properties. As can be seen from Table 3, the pitting potential reaches the maximum value of 916mV at the solid solution temperature of 1050 ℃, which indicates that the experimental steel has excellent pitting corrosion resistance under the conditions; table 4 shows that the intercrystalline sensitivity values of the experimental steel at different solid solution temperatures show a growing trend as a whole, and when the solid solution temperature is 1000 ℃, the intercrystalline sensitivity value is the lowest, which shows that the experimental steel has excellent intercrystalline corrosion resistance under the conditions; in summary, the experimental steel of example 1 is superior to the experimental steel of example 2 in terms of comprehensive mechanical properties and close to it in terms of corrosion resistance.
Example 3
2205 duplex stainless steel: the stainless steel casting blank comprises the following chemical components in percentage by mass: c: 0.022%, Si: 0.31%, Mn: 1.35%, S: 0.0005%, P: 0.021%, Cr: 22.38%, Ni: 4.72%, Mo: 3.06%, Cu: 0.27%, N: 0.0175%, the balance being iron and inevitable impurities.
(1) A stainless steel cast ingot was produced by a vacuum melting furnace of 50 kg.
(2) The stainless steel casting blank is pre-forged, the forging is started at 1000 ℃, the forging ratio is 4, the finish forging temperature is 1150 ℃, the stainless steel casting blank is forged into a plate blank with the width of 130mm and the thickness of 30mm, and the stainless steel casting blank is rapidly cooled after being forged.
(3) And (3) carrying out pre-rolling treatment, setting the initial rolling temperature to be 1120 ℃, setting the final rolling temperature to be 980 ℃, and carrying out water quenching to obtain the plate.
(4) In order to avoid the formation of sigma brittle phase in the process of solid solution treatment, the solid solution temperature interval without precipitated phase obtained by Thermo-Calc software phase precipitation thermodynamic calculation is between 1000 ℃ and 1150 ℃, wherein the two-phase equilibrium point is 1050 ℃, and a two-phase equilibrium phase diagram is arranged in figure 7.
(5) And (4) carrying out solid solution treatment on the plate obtained in the step (3) under the conditions of 1000 ℃, 1050 ℃ and 1150 ℃ solid solution temperature for 0.5h, 1h, 1.5h, 2h and 5h respectively, wherein the heating rate is 12 ℃/min, and then quenching and cooling.
(6) Respectively processing the samples subjected to the solution treatment in the step (5) into
Figure BDA0003719342840000091
Tensile and impact test specimens of 10mm by 55 mm. The mechanical properties data are collated in FIG. 5.
And (4) cutting the sample impacted in the step (6) into a cuboid with the thickness of 10 mm-30 mm, and then carrying out sealing insulation treatment on the non-working surface of the sample to prepare for the pitting corrosion and intergranular corrosion experiments.
Preparing a pitting solution and an intercrystalline corrosion solution, wherein the pitting solution is a 3.5 wt% NaCl solution (1000 mLH) 2 Prepared from O and 35g NaCl) is H 2 SO 4 NaCl and KSCN in a molar ratio of 1.2:1.1:0.01 (1000mL H) 2 O、54.35mL H 2 SO 4 29.25g of NaCl and 0.97g of KSCN); testing pitting corrosion performance and intergranular corrosion performance at different solid solution temperatures by using a cyclic voltammetric potentiodynamic polarization curve and a double-ring potentiodynamic reactivation method (DLEPR); the measured polarization curve is shown in FIG. 9, electrochemical parameter adjustment by potential polarization curve fittingIn Table 5; FIG. 10 is a graph comparing the dual-ring electrochemical potentiodynamic reactivation test curve and the intercrystalline sensitivity value of the experimental steel at different solid solution temperatures and times.
TABLE 5
Solid solution temperature E coor /V I corr /A cm - 2 E b /V E b -E coor
1000℃-0.5h -0.538 9.010*10 -7 1.095 1.633
1050℃-0.5h -0.338 10.061*10 -8 1.151 1.489
1150℃-0.5h -0.480 3.054*10 -6 1.123 1.603
1000℃-1h -0.285 15.5*10 -8 1.141 1.426
1050℃-1h -0.342 12.9*10 -8 1.138 1.480
1150℃-1h -0.296 20.1*10 -8 1.144 1.440
1000℃-1.5h -0.287 2.978*10 -7 1.03 1.317
1050℃-1.5h -0.365 1.57*10 -6 1.11 1.475
1150℃-1.5h -0.344 5.98*10 -7 1.061 1.405
1000℃-2h -0.294 16.2*10 -8 1.131 1.425
1050℃-2h -0.288 8.66*10 -8 1.135 1.423
1150℃-2h -0.293 13.11*10 -8 1.132 1.426
As can be seen from fig. 8, the elongation after fracture of the 2205 duplex stainless steel is maintained at about 30%, the impact toughness is generally inferior to that of example 1, the impact toughness and plasticity of the 2205 duplex stainless steel are superior to those of the 2205 duplex stainless steel in example 1, the pitting potential of the 2205 duplex stainless steel is generally maintained at about 1.1V, and as can be seen from the polarization curve of fig. 9, the polarization plateau of the 2205 duplex stainless steel is much longer in the whole, indicating that the 2205 duplex stainless steel has excellent pitting corrosion performance, but the pitting potential at the solution temperature of 1050 ℃ for 1h in example 1 is close to that of the comparative example 2. According to FIG. 10, it can be seen that the intergranular sensitivity of 2205 duplex stainless steel shows a decreasing trend, and when the solid solution temperature is 1050 ℃ and the solid solution time is 1.5h, the intergranular sensitivity is less than 2%, under the condition, the steel has good intergranular corrosion resistance, and is close to that of example 1.
Example 4
The stainless steel casting blank comprises the following chemical components in percentage by mass: 0.0148% of C, Si: 0.047%, Mn: 16.792%, S: 0.0035%, P: 0.0066%, Cr: 23.632%, Ni: 0.0255%, Mo: 1.314%, Cu: 0.142%, N: 0.305%, and the balance of iron and inevitable impurities.
(1) A stainless steel cast ingot was produced by a vacuum melting furnace of 50 kg.
(2) The stainless steel casting blank is pre-forged, the forging is started at 1000 ℃, the forging ratio is 3, the finish forging temperature is 1050 ℃, the stainless steel casting blank is forged into a plate blank with the width of 130mm and the thickness of 30mm, and the stainless steel casting blank is rapidly cooled after being forged.
(3) And (3) carrying out pre-rolling treatment, setting the initial rolling temperature to be 1120 ℃, setting the final rolling temperature to be 980 ℃, and carrying out water quenching to obtain the plate.
(4) In order to avoid the formation of sigma brittle phase in the process of solid solution treatment, the solid solution temperature interval without precipitated phase obtained by Thermo-Calc software phase precipitation thermodynamic calculation is 950-1050 ℃, wherein the two-phase equilibrium point is 1000 ℃, and the two-phase equilibrium phase diagram is arranged in figure 11.
(5) And (4) carrying out solid solution treatment on the plate obtained in the step (3) under the conditions of 950 ℃, 1000 ℃ and 1050 ℃ solid solution temperature for 30min, and carrying out quenching cooling at the heating rate of 10 ℃/min.
(6) Respectively processing the samples subjected to the solution treatment in the step (4) into
Figure BDA0003719342840000101
Tensile and impact test specimens of 10mm by 55 mm. The data are collated in Table 6.
And (4) cutting the sample impacted in the step (6) into a cuboid with the thickness of 10 mm-30 mm, and then carrying out sealing insulation treatment on the non-working surface of the sample to prepare for the pitting corrosion and intergranular corrosion experiments.
Preparing a pitting solution and an intercrystalline corrosion solution, wherein the pitting solution is a 3.5 wt% NaCl solution (1000 mLH) 2 Prepared from O and 35g NaCl) is H 2 SO 4 NaCl and KSCN in a molar ratio of 1.2:1.1:0.01 (1000mL H) 2 O、54.35mL H 2 SO 4 29.25g of NaCl and 0.97g of KSCN); and testing the pitting corrosion performance and the intergranular corrosion performance at different solid solution temperatures by using a cyclic voltammetric potentiodynamic polarization curve and a double-ring potentiodynamic reactivation method (DLEPR). Electrochemical parameters fitted to the potential polarization curve are summarized in table 7, fig. 12 is a double-ring electrochemical potentiodynamic reactivation method test curve at different solid solution temperatures, and intercrystalline sensitivity values are summarized in table 8.
TABLE 6
Solid solution temperature 950 1000℃ 1050℃
Elongation after Break (%) 36.5 41.5 44
Tensile strength (MPa) 755 730 737
Impact toughness (MPa) 3.8 176.5 82.2
TABLE 7
Solid solution temperature E coor /V I corr /A cm -2 E b /V E b -E coor
950℃-0.5h -0.529 5.583*10 -7 0.073 0.602
1000℃-0.5h -0.332 1.590*10 -7 0.448 0.780
1050℃-0.5h -0.256 7.021*10 -8 0.319 0.575
TABLE 8
Solid solution temperature 950 1000℃ 1050℃
Intercrystalline sensitivity value (R) a ) 0.32 0.28 0.19
As can be seen from table 5, the elongation after fracture and the impact toughness of example 1 are both more excellent than those of comparative example 3 than those of example 1, and the pitting potential of example 1 is more excellent than that of comparative example 3 according to the pitting potential in table 6. The intergranular sensitivity value of the experimental steel showed a tendency to decrease as a whole, and when the solid solution temperature was 1050 ℃, the intergranular sensitivity value was 0.19, which is equivalent to the intergranular sensitivity value of example 1.
According to the above embodiment, the results can be obtained, the solid solution temperature of the high-manganese ultralow-nickel duplex stainless steel in the embodiment 1 is 1030 ℃ and 1070 ℃, the temperature rise rate is 10-12 ℃/min and the high-manganese ultralow-nickel duplex stainless steel has good mechanical properties; the solid solution temperature is 1080-1120 ℃, the temperature is 50-70min, the heating rate is 10-12 ℃/min, and the plasticity is good; the solid solution temperature is 980 and 1020 ℃, the temperature is 50-70min, the heating rate is 10-13 ℃/min, and the pitting corrosion resistance is good; the solid solution temperature is 1070 ℃ at 1030 ℃ and 1070 ℃, the temperature rise rate is 10-12 ℃/min, and the alloy has excellent intergranular corrosion resistance, to sum up, the temperature rise rate is 10-12 ℃/min at 1030 ℃ and 50-80min, the quenching cooling is carried out, the elongation after fracture exceeds 48%, the impact toughness exceeds 268J, the tensile strength exceeds 725MPa, the pitting potential exceeds 760mV, and the intergranular sensitivity value is lower than 30%, so that the optimal mechanical property and corrosion resistance are obtained.
Compared with 2205 duplex stainless steel, the stainless steel has the advantages of lower cost, more excellent mechanical property and great application potential, and can be widely applied to the fields of structural materials such as food industry, chemical treatment containers, construction steel bars and the like.

Claims (7)

1. A method for optimizing the performance of duplex stainless steel is characterized in that: the manganese-nickel-substituted nickel-saving duplex stainless steel with the best performance is obtained by designing chemical components of the duplex stainless steel and combining with solid solution treatment;
the duplex stainless steel comprises the following chemical components in percentage by mass: c:0.01 to 0.03 percent; si: 0.03-0.05%; mn: 8% -10%; p: 0.005-0.007%; cr: 20% -22%; ni: 0.4% -0.7%; mo: 0.9 to 1.2 percent; cu: 0.2 to 0.4 percent; n: 0.15 to 0.3 percent; the balance of iron element and inevitable impurities;
carrying out solution treatment on the duplex stainless steel plate, and then cooling by water at normal temperature;
when the solution treatment conditions are as follows: obtaining the best plasticity performance at 1080 and 1120 ℃ for 50-70min and the heating rate of 10-12 ℃/min;
when the solution treatment conditions are as follows: obtaining the best obdurability at 1030 ℃ and 1070 ℃ and 100 ℃ and 130 min;
when the solution treatment conditions are as follows: obtaining the optimal pitting corrosion resistance at 980 and 1020 ℃ for 50-70min and at the heating rate of 10-13 ℃/min;
when the solution treatment conditions are as follows: obtaining the best intergranular corrosion resistance at 1030-1070 ℃ for 50-70min and at the heating rate of 10-12 ℃/min;
when the solution treatment conditions are as follows: the best mechanical property and corrosion resistance can be obtained at the temperature of 980 ℃ and 1030 ℃ for 50-80min and the heating rate of 10-12 ℃/min.
2. Method for optimizing the properties of duplex stainless steel according to claim 1, characterized in that: the impurities are Ca and S, wherein the mass percent of Ca in the duplex stainless steel is less than or equal to 0.01 percent, and the mass percent of S in the duplex stainless steel is less than or equal to 0.005 percent.
3. Method for optimizing the properties of duplex stainless steel according to claim 1 or 2, characterized in that: in order to avoid the formation of sigma brittle phase in the process of solution treatment and keep the minimum content of two phases higher than 30%, the solid solution temperature interval without precipitated phase obtained by thermodynamic calculation of precipitated phase of Thermo-Calc software is larger than 950 ℃ and less than or equal to 1250 ℃.
4. Method for optimizing the properties of duplex stainless steel according to claim 1 or 2, characterized in that: the preparation method of the duplex stainless steel plate specifically comprises the following steps:
(1) smelting in a vacuum smelting furnace according to the component proportion to obtain an ultralow Ni type duplex stainless steel ingot;
(2) forging the cast ingot obtained in the step (1) into a plate blank, and quickly cooling the plate blank after forging;
(3) homogenizing the plate blank obtained in the step (2), and then quenching and cooling;
(4) and (4) carrying out hot rolling deformation on the plate blank obtained in the step (3), and carrying out water quenching on the hot rolled steel plate to obtain the high-Mn ultralow-Ni duplex stainless steel plate.
5. Method for optimizing the properties of duplex stainless steel according to claim 4, characterized in that: the forging treatment conditions in the step (2) are as follows: starting forging at 950-1200 ℃, wherein the forging ratio is 3-4, the finish forging temperature is more than or equal to 980 ℃, and cooling after forging.
6. Method for optimizing the properties of duplex stainless steel according to claim 4, characterized in that: the tissue homogenization treatment in the step (3) is performed at the temperature of 1100 +/-20 ℃ and the temperature is kept for 100-.
7. Method for optimizing the properties of duplex stainless steel according to claim 4, characterized in that: the initial rolling temperature in the hot rolling deformation process of the step (4) is 970-1180 ℃, and the final rolling temperature is more than or equal to 960 ℃.
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Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101613839A (en) * 2008-06-23 2009-12-30 宝山钢铁股份有限公司 A kind of high nitrogen and low nickel duplex stainless steel and manufacture method thereof
CN110484817A (en) * 2019-09-02 2019-11-22 鞍钢股份有限公司 A method of eliminating ultra-wide economizing type two phase stainless steel surface crack of plate
CN113215489A (en) * 2021-05-08 2021-08-06 昆明理工大学 High-strength-plasticity low-chromium nickel-saving type duplex stainless steel and stretching preparation method thereof

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN101613839A (en) * 2008-06-23 2009-12-30 宝山钢铁股份有限公司 A kind of high nitrogen and low nickel duplex stainless steel and manufacture method thereof
CN110484817A (en) * 2019-09-02 2019-11-22 鞍钢股份有限公司 A method of eliminating ultra-wide economizing type two phase stainless steel surface crack of plate
CN113215489A (en) * 2021-05-08 2021-08-06 昆明理工大学 High-strength-plasticity low-chromium nickel-saving type duplex stainless steel and stretching preparation method thereof

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
李学锋 等: "固溶温度对00Cr21Mn5Ni1N节镍型双相不锈钢组织双相不锈钢组织和性能的影响", 钢铁研究学报, vol. 19, no. 10, pages 44 - 47 *

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