Preparation method of high-hardness wear-resistant stainless steel composite board

Abstract

The invention provides a preparation method of a high-hardness wear-resistant stainless steel composite board. The preparation method comprises the following steps: providing a steel billet; a hot rolling step in which the steel billet is hot-rolled to obtain a hot-rolled steel sheet; a first annealing step for heating the hot-rolled steel sheet to a temperature range of 600-880 DEG C at a heating rate of 50-80 DEG C / s, and performing a first annealing treatment; a cold rolling step in which the steel sheet subjected to the first annealing treatment is cold-rolled to obtain a cold-rolled steel sheet; a second annealing step of heating the cold-rolled steel sheet at a heating rate of 30 DEG C / s-40 DEG C / s to a temperature range of 600 DEG C-750 DEG C for second annealing treatment; and a heat treatment procedure: carrying out heat treatment on the steel plate subjected to the second annealing treatment to obtain the stainless steel composite plate. According to the preparation method, the obtained stainless steel composite board has excellent properties such as wear resistance, good processability and the like.

Description

Technical Field

[0001] The invention relates to the technical field of stainless steel, and in particular to a method for preparing a high-hardness and wear-resistant stainless steel composite plate. Background Art

[0002] In the field of engineering machinery, wear-resistant stainless steel composite plates are usually used as steel to increase the service life of engineering machinery. With the rapid development of industry and technology, the comprehensive performance requirements for stainless steel composite plates prepared by traditional preparation methods are becoming higher and higher. For example, stainless steel composite plates need to have wear resistance while also taking into account requirements such as good processing performance. Therefore, it is urgent to develop a preparation method for high-hardness and wear-resistant stainless steel composite plates. Summary of the invention

[0003] In order to solve the above technical problems, the present invention provides a method for preparing a high-hardness and wear-resistant stainless steel composite plate. The preparation method can make the obtained stainless steel composite plate have not only wear resistance but also excellent properties such as good processing performance.

[0004] The present invention provides a method for preparing a high-hardness and wear-resistant stainless steel composite plate, comprising: A steel billet is provided, wherein the composition of the steel billet is, by mass percentage, C: 0.2% to 0.55%, Mn: 0.1% to 0.4%, Cr: 12.0% to 15.0%, Si: 0.4% to 0.8%, B: 0.005% to 0.02%, Ni: 0.5% to 0.8%, Cu: 0.05% to 0.2%, Nb: 0.01% to 0.1%, Al: 0.01% to 0.1%, Mo: 0.5% to 1.0%, W: 0.3% to 0.9%, Ca: 0.001% to 0.01%, Y: 0.02% to 0.08%, P: ≤0.003%, S: ≤0.004%, N: ≤0.0035%, and the balance is Fe and other inevitable impurity elements; A hot rolling process is to hot-roll the steel billet to obtain a hot-rolled steel plate; A first annealing step, heating the hot-rolled steel plate to a temperature range of 600°C to 880°C at a heating rate of 50°C / s to 80°C / s for a first annealing treatment; A cold rolling process, cold rolling the steel sheet after the first annealing treatment to obtain a cold rolled steel sheet; A second annealing process, heating the cold-rolled steel sheet to a temperature range of 600°C to 750°C at a heating rate of 30°C / s to 40°C / s for a second annealing treatment; The heat treatment step is to heat treat the steel plate after the second annealing treatment to obtain a stainless steel composite plate.

[0005] According to any of the foregoing embodiments of the present invention, the hot rolling process comprises: A rough rolling step, performing rough rolling on the steel billet, wherein the starting rolling temperature of the rough rolling is 1150° C. to 1300° C., and the finishing rolling temperature of the rough rolling is 950° C. to 1080° C.; A finishing rolling step, performing finishing rolling on the steel plate after rough rolling, wherein the starting rolling temperature of the finishing rolling is 850° C. to 920° C., and the final rolling temperature of the finishing rolling is 800° C. to 840° C.; In the coiling step, the finish-rolled steel sheet is cooled to below 500°C at a cooling rate of 100°C / s to 150°C / s, and the hot-rolled steel sheet is obtained by coiling.

[0006] According to any of the aforementioned embodiments of the present invention, in the finish rolling step, the reduction ratio of the finish rolling is 85% to 95%.

[0007] According to any of the foregoing embodiments of the present invention, the first annealing step comprises: The first heating step is to heat the hot-rolled steel plate to a temperature range of 600°C to 880°C at a heating rate of 50°C / s to 80°C / s; The first heat preservation step is to keep the hot-rolled steel plate in a temperature range of 600° C. to 880° C. for 5 h to 36 h; The first cooling step is to cool the hot-rolled steel plate after the first heat preservation step to below 400° C. at a cooling rate of 10° C. / s to 30° C. / s.

[0008] According to any of the aforementioned embodiments of the present invention, the reduction ratio in the cold rolling process is 40% to 60%.

[0009] According to any of the foregoing embodiments of the present invention, the second annealing process comprises: The second heating step is to heat the cold-rolled steel sheet to a temperature range of 600°C to 750°C at a heating rate of 30°C / s to 40°C / s; The second heat preservation step is to keep the cold-rolled steel plate in a temperature range of 600° C. to 750° C. for 2 h to 12 h; The second cooling step is to cool the cold-rolled steel sheet after the second heat preservation step to below 350° C. at a cooling rate of 5° C. / s to 15° C. / s.

[0010] According to any of the foregoing embodiments of the present invention, the heat treatment process comprises: Normalizing step: heating the steel plate in the second annealing process to 900°C~1000°C at a heating rate of 90°C / s~110°C / s and keeping it at that temperature for 1h~2h before cooling.

[0011] According to any of the foregoing embodiments of the present invention, the heat treatment process further comprises: a quenching step, heating the steel plate after the normalizing step to 700° C. to 850° C. and keeping the temperature for 30 min to 60 min, and then cooling the steel plate to below 250° C. at a cooling rate of 10° C. / s to 50° C. / s for quenching; In the tempering step, the steel plate after the quenching step is heated to 200°C to 300°C and kept at this temperature for 20min to 40min, and then cooled to room temperature at a cooling rate of 30°C / s to 70°C / s for tempering to obtain a stainless steel composite plate.

[0012] According to any of the foregoing embodiments of the present invention, the quenching step comprises: In a first quenching step, the steel plate after the normalizing step is heated to 400°C to 600°C at a heating rate of 60°C / s to 80°C / s and kept at that temperature for 30min to 60min; The third cooling step is to cool the steel plate after the first quenching step to below 250° C. at a cooling rate of 20° C. / s to 40° C. / s.

[0013] According to any of the foregoing embodiments of the present invention, in the steel billet, the contents of C, N, Si, Cr, W and B satisfy 13.5%≤C+N+Si+Cr+W+B≤16.5%.

[0014] The method for preparing a high-hardness and wear-resistant stainless steel composite plate provided by the present invention reasonably selects the components and contents of the steel billet and optimizes the steps in the preparation method, so that the prepared stainless steel composite plate has both wear resistance and excellent properties such as good processing performance.

[0015] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for use in the embodiments are briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without creative work.

[0017] Figure 1 A schematic diagram showing a process of preparing a high-hardness and wear-resistant stainless steel composite plate material according to some embodiments of the present invention; Figure 2 A schematic diagram showing a process of preparing a high-hardness and wear-resistant stainless steel composite plate material according to other embodiments of the present invention; Figure 3 A schematic diagram showing a process of preparing a high-hardness and wear-resistant stainless steel composite plate material according to some other embodiments of the present invention; Figure 4 A schematic diagram showing a process of preparing a high-hardness and wear-resistant stainless steel composite plate material according to some other embodiments of the present invention; Figure 5 A schematic diagram showing a process of preparing a high-hardness and wear-resistant stainless steel composite plate material according to some other embodiments of the present invention; Figure 6 A schematic diagram showing a process of preparing a high-hardness and wear-resistant stainless steel composite plate material according to some other embodiments of the present invention; Figure 7 A schematic flow chart of a method for preparing a high-hardness and wear-resistant stainless steel composite plate material is shown in some other embodiments of the present invention. DETAILED DESCRIPTION

[0018] The "range" disclosed in the present invention is defined in the form of a lower limit and an upper limit. A given range is defined by selecting a lower limit and an upper limit, and the selected lower limit and upper limit define the boundaries of the particular range. The range defined in this way can be inclusive or exclusive of the end values, and can be arbitrarily combined, that is, any lower limit can be combined with any upper limit to form a range.

[0019] If not otherwise specified, all embodiments and optional embodiments of the present invention may be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present invention.

[0020] If not otherwise specified, all technical features and optional technical features of the present invention may be combined with each other to form new technical solutions, and such technical solutions should be deemed to be included in the disclosure of the present invention.

[0021] If not otherwise specified, all steps of the present invention may be performed sequentially or randomly, preferably sequentially. For example, the method includes steps (a) and (b), which means that the method may include steps (a) and (b) performed sequentially, or may include steps (b) and (a) performed sequentially. For example, the method may further include step (c), which means that step (c) may be added to the method in any order, for example, the method may include steps (a), (b) and (c), or may include steps (a), (c) and (b), or may include steps (c), (a) and (b), etc.

[0022] If there is no special explanation, the "include" and "comprising" mentioned in the present invention represent open-ended or closed-ended expressions. For example, the "include" and "comprising" may represent that other components not listed may also be included or only the listed components may be included or only the listed components may be included.

[0023] If not specifically stated, in the present invention, the term "or" is inclusive. For example, the phrase "A or B" means "A, B, or both A and B". More specifically, any of the following conditions satisfies the condition "A or B": A is true (or exists) and B is false (or does not exist); A is false (or does not exist) and B is true (or exists); or both A and B are true (or exist).

[0024] Unless otherwise specified, the terms used in the present invention have the commonly understood meanings that are generally understood by those skilled in the art.

[0025] Unless otherwise specified, the values ​​of the parameters mentioned in the present invention can be measured by various test methods commonly used in the art, for example, they can be measured according to the test methods given in the embodiments of the present invention.

[0026] See also Figure 1 As shown, the present invention provides a method for preparing a high-hardness and wear-resistant stainless steel composite plate, comprising: S100. A steel billet is provided. The steel billet comprises, by mass percentage, the following components: C: 0.2% to 0.55%, Mn: 0.1% to 0.4%, Cr: 12.0% to 15.0%, Si: 0.4% to 0.8%, B: 0.005% to 0.02%, Ni: 0.5% to 0.8%, Cu: 0.05% to 0.2%, Nb: 0.01% to 0.1%, Al: 0.01% to 0.1%, Mo: 0.5% to 1.0%, W: 0.3% to 0.9%, Ca: 0.001% to 0.01%, Y: 0.02% to 0.08%, P: ≤0.003%, S: ≤0.004%, N: ≤0.0035%, and the balance is Fe and other inevitable impurity elements; S200, hot rolling process, hot rolling the steel billet to obtain a hot rolled steel plate; S300, a first annealing step, heating the hot-rolled steel sheet to a temperature range of 600°C to 880°C at a heating rate of 50°C / s to 80°C / s for a first annealing treatment; S400, a cold rolling process, cold rolling the steel sheet after the first annealing treatment to obtain a cold-rolled steel sheet; S500, a second annealing process, heating the cold-rolled steel sheet to a temperature range of 600°C to 750°C at a heating rate of 30°C / s to 40°C / s for a second annealing treatment; S600, a heat treatment step, heat treating the steel plate that has undergone the second annealing treatment to obtain a stainless steel composite plate.

[0027] The method for preparing a high-hardness and wear-resistant stainless steel composite plate provided by the present invention reasonably selects the components and contents of the steel billet and optimizes the steps in the preparation method, so that the prepared stainless steel composite plate has both wear resistance and excellent properties such as good processing performance.

[0028] Next, S100 to S600 will be described.

[0029] In an embodiment of the present invention, the composition of the steel billet includes the following elements.

[0030] C: 0.2%~0.55% The C element is one of the main elements for improving the hardness of the stainless steel composite plate. If the C content is lower than the lower limit of the above range, the hardness of the stainless steel composite plate is insufficient, so that its wear resistance cannot meet the requirements; if the C content is higher than the upper limit of the above range, a large amount of carbides are easily formed, which leads to a decrease in the corrosion resistance of the stainless steel composite plate. Therefore, the C content in the steel billet of the embodiment of the present invention needs to be controlled within the range of 0.2% to 0.55%.

[0031] Mn: 0.1%~0.4% The Mn element is used to improve the toughness of the stainless steel composite plate after quenching to improve its processing performance. If the Mn content is lower than the lower limit of the above range, the toughness of the stainless steel composite plate is insufficient, thereby reducing its processing performance; if the Mn content exceeds the upper limit of the above range, the corrosion resistance of the stainless steel composite plate will decrease. Therefore, the Mn content in the steel billet of the embodiment of the present invention needs to be controlled within the range of 0.1% to 0.4%.

[0032] Cr: 12.0%~15.0% Cr element is the main element used to improve the corrosion resistance of stainless steel composite plates in the martensitic system. If the Cr content is lower than the lower limit of the above range, the corrosion resistance of the stainless steel composite plate will decrease. If the Cr content is higher than the upper limit of the above range, the austenite structure therein will increase, thereby reducing the hardness and wear resistance of the stainless steel composite plate. Therefore, the Cr content in the steel billet provided in the embodiment of the present invention needs to be controlled within the range of 12.0% to 15.0%.

[0033] Si: 0.4% to 0.8% Si is used to improve the oxidation resistance of the steel billet during high temperature and the ductility of the stainless steel composite plate, thereby helping to improve the corrosion resistance and processing performance of the stainless steel composite plate. If the Si content is lower than the lower limit of the above range, the antioxidant effect is poor, which in turn increases the carbide and reduces the corrosion resistance. If the Si content is higher than the upper limit of the above range, the ductility of the stainless steel composite plate decreases, which is not conducive to improving the processing performance. Therefore, the Si content in the steel billet provided in the embodiment of the present invention needs to be controlled within the range of 0.4% to 0.8%.

[0034] B: 0.005%~0.02% The B element is one of the elements used to improve processing performance and hardness. If the B element is lower than the lower limit of the above range, the hardness and processing performance will decrease. If the B content is higher than the upper limit of the above range, it may cause the composite precipitation of borides and carbides, which will lead to poor quenching effect, which is not conducive to the improvement of processing performance. Therefore, the B content in the steel billet provided in the embodiment of the present invention needs to be controlled in the range of 0.005% to 0.02%.

[0035] Ni: 0.5% to 0.8% The Ni element is also used to improve the toughness of the stainless steel composite plate after quenching to improve its processing performance. If the Ni content is lower than the lower limit of the above range, the toughness of the stainless steel composite plate will be insufficient, thereby reducing its processing performance; if the Ni content exceeds the upper limit of the above range, the corrosion resistance of the stainless steel composite plate will decrease. Therefore, the Ni content in the steel billet of the embodiment of the present invention needs to be controlled within the range of 0.5% to 0.8%.

[0036] Cu: 0.05%~0.2% The Cu element is used to improve the corrosion resistance and processing performance of the stainless steel composite plate. If the content of the Cu element is lower than the lower limit of the above range or higher than the upper limit of the above range, the processing performance or corrosion resistance will be reduced. Therefore, the Cu content in the steel billet of the embodiment of the present invention needs to be controlled in the range of 0.05% to 0.2%.

[0037] Nb: 0.01%~0.1% The Nb element is used to improve the hardness and processing performance of the stainless steel composite plate. If the Nb content is lower than the lower limit of the above range, the improvement of the hardness and processing performance of the stainless steel composite plate is insufficient. If the Nb content is higher than the upper limit of the above range, the processing performance of the stainless steel composite plate is reduced. Therefore, the Nb content in the steel billet of the embodiment of the present invention needs to be controlled in the range of 0.01% to 0.1%.

[0038] Al: 0.01%~0.1% The Al element is used to improve the corrosion resistance and processing performance of the stainless steel composite plate. If the Al content is lower than the lower limit of the above range, it is not conducive to improving the corrosion resistance and processing performance of the stainless steel composite plate. If the Al content is higher than the upper limit of the above range, the hardness of the stainless steel composite plate will be reduced, which is not conducive to improving its wear resistance. Therefore, the Al content in the steel billet of the embodiment of the present invention needs to be controlled in the range of 0.01% to 0.1%.

[0039] Mo: 0.5%~1.0% The Mo element is one of the elements used to improve the corrosion resistance of the stainless steel composite plate. If the Mo content is lower than the lower limit of the above range, the improvement of the corrosion resistance of the stainless steel composite plate is limited. If the Mo content is higher than the upper limit of the above range, the corrosion resistance of the stainless steel composite plate will be reduced. Therefore, the Mo content in the steel billet of the embodiment of the present invention needs to be controlled in the range of 0.5% to 1.0%.

[0040] W: 0.3%~0.9% The W element is used to improve the corrosion resistance and hardness of the stainless steel composite plate. If the W content is lower than the lower limit of the above range, it is not conducive to improving the corrosion resistance and hardness of the stainless steel composite plate. If the W content is higher than the upper limit of the above range, the processing performance of the stainless steel composite plate is reduced. Therefore, the W content in the steel billet of the embodiment of the present invention needs to be controlled in the range of 0.3% to 0.9%.

[0041] Ca: 0.001%~0.01% The Ca element is used to reduce the formation of sulfides in the stainless steel composite plate to improve the processing performance of the stainless steel composite plate. If the Ca content is lower than the lower limit of the above range, the amount of reducing the formation of sulfides is limited. If the Ca content is higher than the upper limit of the above range, it will lead to a decrease in the toughness of the stainless steel composite plate, which is not conducive to improving its processing performance. Therefore, the Ca content provided in the embodiment of the present invention needs to be controlled in the range of 0.001% to 0.01%.

[0042] Y: 0.02%~0.08% The Y element is used to improve the hardness and processing performance of the stainless steel composite plate. If the Y content is lower than the lower limit of the above range, the improvement of the hardness and processing performance of the stainless steel composite plate is limited. If the Y content is higher than the above range, the toughness of the stainless steel composite plate will be reduced, thereby reducing its processing performance. Therefore, the Y content provided in the embodiment of the present invention needs to be controlled in the range of 0.02% to 0.08%.

[0043] P: ≤0.003%, S: ≤0.004% P and S are harmful elements, which are unavoidable. If their contents exceed the upper limits of the above ranges, the processing performance and corrosion resistance of the stainless steel composite plate will be reduced. Therefore, the P content provided in the embodiment of the present invention needs to be controlled within a range of less than or equal to 0.003%, and the S content needs to be controlled within a range of less than or equal to 0.004%.

[0044] N: ≤0.0035% The N element is used to improve the hardness and corrosion resistance of the stainless steel composite plate. If the N content is higher than the upper limit of the above range, it is not conducive to improving the hardness and corrosion resistance of the stainless steel composite plate. Therefore, the N content provided in the embodiment of the present invention needs to be controlled within a range of less than or equal to 0.0035%.

[0045] In the steel billet provided in the embodiment of the present invention, in addition to the above-mentioned components, the remainder is Fe and other inevitable impurity elements. It should be noted that the impurity elements here generally refer to the impurity components mixed with raw materials such as ore and waste or various reactants in the preparation process when preparing the stainless steel composite plate in the embodiment of the present invention. Exemplarily, the O element is an impurity that is mixed into the steel during the raw materials and the preparation process.

[0046] In some embodiments of the present invention, in the steel billet, the contents of C, N, Si, Cr, W and B satisfy 13.5%≤C+N+Si+Cr+W+B≤16.5%. When the contents of C, N, Si, Cr, W and B satisfy the above relationship, the corrosion resistance, processing performance and wear resistance of the stainless steel composite plate can be further improved.

[0047] See also Figure 2 As shown, in some embodiments of the present invention, the hot rolling process includes: S210, a rough rolling step, performing rough rolling on the steel billet, wherein the starting rolling temperature of the rough rolling is 1150° C. to 1300° C., and the final rolling temperature of the rough rolling is 950° C. to 1080° C.; In the above-mentioned rough rolling step, the starting rolling temperature and the final rolling temperature are respectively set within the above-mentioned ranges, which can help to improve the rolling efficiency and also facilitate the subsequent processes.

[0048] S220, a finishing rolling step, performing finishing rolling on the steel plate after rough rolling, wherein the starting rolling temperature of the finishing rolling is 850°C to 920°C, and the final rolling temperature of the finishing rolling is 800°C to 840°C; In the above-mentioned finishing rolling step, the starting rolling temperature and the final rolling temperature of the finishing rolling are set within the above-mentioned range, which can help to improve the subsequent hardenability and improve the hardness and processing performance of the stainless steel composite plate.

[0049] In some embodiments of the present invention, the reduction ratio of the finishing rolling is 85% to 95%. The finishing rolling reduction ratio within the above range can help improve the toughness and hardness of the stainless steel composite plate, thereby improving its processing performance and wear resistance.

[0050] S230, a coiling step, cooling the finish-rolled steel plate to below 500°C at a cooling rate of 100°C / s to 150°C / s, and obtaining a hot-rolled steel plate by coiling.

[0051] In the coiling step, the finish-rolled steel plate is cooled at the cooling rate, which can help improve the toughness of the stainless steel composite plate and thus improve its processing performance.

[0052] See also Figure 3 As shown, in some embodiments of the present invention, the first annealing process includes: S310, a first heating step, heating the hot-rolled steel plate to a temperature range of 600°C to 880°C at a heating rate of 50°C / s to 80°C / s; In the first heating step, when the hot-rolled steel plate is heated to the above range at the above heating rate, the internal stress can be quickly eliminated and the ductility can be improved, thereby improving the processing performance of the steel plate.

[0053] S320, a first heat preservation step, keeping the hot-rolled steel plate in a temperature range of 600° C. to 880° C. for 5 h to 36 h; In the first heat preservation step, the hot rolled steel plate is kept in the above range for 5 hours to 36 hours, which can help to form the desired metallographic structure, thereby improving the hardness and processing performance of the steel plate.

[0054] S330, a first cooling step, cooling the hot-rolled steel plate after the first heat preservation step to below 400°C at a cooling rate of 10°C / s to 30°C / s.

[0055] In some embodiments of the present invention, the reduction ratio in the cold rolling process is 40% to 60%. When the reduction ratio in the cold rolling process is within the above range, it can further help to improve the hardness and surface quality of the stainless steel composite plate.

[0056] See also Figure 4 As shown, in some embodiments of the present invention, the second annealing process includes: S510, a second heating step, heating the cold-rolled steel sheet to a temperature range of 600°C to 750°C at a heating rate of 30°C / s to 40°C / s; S520, a second heat preservation step, keeping the cold-rolled steel plate in a temperature range of 600° C. to 750° C. for 2 h to 12 h; S530, a second cooling step, cooling the cold-rolled steel sheet after the second heat preservation step to below 350°C at a cooling rate of 5°C / s to 15°C / s.

[0057] See also Figure 5 As shown, in some embodiments of the present invention, the heat treatment process includes: S610, normalizing step, heating the steel plate in the second annealing process to 900°C~1000°C at a heating rate of 90°C / s~110°C / s and keeping it at that temperature for 1h~2h before cooling.

[0058] Please refer to Figure 6, in some embodiments of the present invention, the heat treatment process further includes: S620, a quenching step, heating the steel plate after the normalizing step to 700°C to 850°C and keeping the temperature for 30min to 60min, and then cooling the steel plate to below 250°C at a cooling rate of 10°C / s to 50°C / s for quenching; S630, tempering step, heating the steel plate after the quenching step to 200°C~300°C and keeping it warm for 20min~40min, and then cooling it to room temperature at a cooling rate of 30°C / s~70°C / s for tempering to obtain a stainless steel composite plate.

[0059] See also Figure 7 As shown, in some embodiments of the present invention, the quenching step includes: S621, a first quenching step, heating the steel plate after the normalizing step to 400°C~600°C at a heating rate of 60°C / s~80°C / s and keeping the temperature for 30min~60min; S624, a third cooling step, cooling the steel plate after the first quenching step to below 250°C at a cooling rate of 20°C / s to 40°C / s.

[0060] The following embodiments describe the disclosure of the present invention in more detail, and these embodiments are only for illustrative purposes, because it is obvious to those skilled in the art that various modifications and variations are made within the scope of the disclosure of the present invention. Unless otherwise stated, all parts, percentages and ratios reported in the following embodiments are based on mass, and all reagents used in the embodiments are commercially available or synthesized according to conventional methods, and can be used directly without further processing, and the instruments used in the embodiments are commercially available.

[0061] Example 1

[0062] This embodiment provides a method for preparing a high-hardness and wear-resistant stainless steel composite plate, comprising: A 60 mm thick steel billet is provided, wherein the composition of the steel billet is, by mass percentage, 0.35% C, 0.15% Mn, 12.5% ​​Cr, 0.5% Si, 0.015% B, 0.65% Ni, 0.1% Cu, 0.05% Nb, 0.05% Al, 0.7% Mo, 0.6% W, 0.005% Ca, 0.04% Y, 0.001% P, 0.002% S, 0.0025% N, and the balance is Fe and other inevitable impurity elements; The steel billet is subjected to rough rolling, wherein the starting rolling temperature of the rough rolling is 1250° C. and the final rolling temperature of the rough rolling is 1000° C.; The steel plate after rough rolling is subjected to finish rolling, wherein the start rolling temperature of the finish rolling is 900°C, the final rolling temperature of the finish rolling is 820°C, and the reduction rate of the finish rolling is 90%; The finished rolled steel plate is cooled to 400°C at a cooling rate of 120°C / s, and a 6mm thick hot rolled steel plate is obtained by coiling; A first heating step of heating the hot rolled steel sheet to a temperature range of 850° C. at a heating rate of 70° C. / s; The first heat preservation step is to keep the hot-rolled steel sheet after the first heating step in a temperature range of 780° C. for 16 hours; A first cooling step of cooling the hot-rolled steel sheet after the first heat preservation step to 300° C. at a cooling rate of 20° C. / s; The steel sheet subjected to the first annealing treatment is cold rolled to obtain a cold rolled steel sheet, wherein the cold rolling reduction ratio is 50%; a second heating step of heating the cold rolled steel sheet to a temperature range of 700° C. at a heating rate of 35° C. / s; A second heat preservation step of heat-preserving the cold-rolled steel sheet after the second heating step within a temperature range of 650° C. for 5 hours; A second cooling step of cooling the cold-rolled steel sheet after the second heat preservation step to 250° C. at a cooling rate of 10° C. / s; Normalizing step, heating the steel plate in the second annealing process to 950°C at a heating rate of 100°C / s and keeping the temperature for 1 hour before cooling; The steel plate after the normalizing step is heated to a first quenching step of 500° C. at a heating rate of 75° C. / s; A third cooling step of cooling the steel plate after the first quenching step to 150° C. at a cooling rate of 25° C. / s; The steel plate after the third cooling step was heated to 200° C. and kept at this temperature for 25 minutes, and then cooled to room temperature at a cooling rate of 60° C. / s for tempering to obtain a stainless steel composite plate.

[0063] Examples 2 to 11 and Comparative Examples 1 to 3 The preparation method is similar to that in Example 1, except for the differences shown in Table 1 and Table 2.

[0064] Table 1 lists the components of the steel billets in the embodiments and comparative examples. Please refer to Table 1 for details.

[0065] Table 1 Composition of the steel billets in Examples 1 to 11 and Comparative Examples 1 to 3 Composition C Mn Cr Si B Ni Cu Nb Al Mo W Ca Y P S N Example 1 0.35% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.63% 0.005% 0.04% 0.001% 0.002% 0.0025% Example 2 0.42% 0.20% 13.0% 0.64% 0.018% 0.55% 0.15% 0.04% 0.08% 0.81% 0.84% 0.007% 0.05% 0.002% 0.001% 0.003% Example 3 0.51% 0.35% 14.1% 0.45% 0.009% 0.71% 0.09% 0.08% 0.06% 0.75% 0.76% 0.008% 0.03% 0.001% 0.003% 0.0015% Example 4 0.27% 0.29% 13.2% 0.59% 0.012% 0.59% 0.052% 0.03% 0.09% 0.63% 0.39% 0.002% 0.07% 0.001% 0.004% 0.0035% Example 5 0.35% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.63% 0.005% 0.04% 0.001% 0.002% 0.0025% Example 6 0.35% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.63% 0.005% 0.04% 0.001% 0.002% 0.0025% Example 7 0.35% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.63% 0.005% 0.04% 0.001% 0.002% 0.0025% Example 8 0.35% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.36% 0.005% 0.04% 0.001% 0.002% 0.0025% Example 9 0.35% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.36% 0.005% 0.04% 0.001% 0.002% 0.0025% Example 10 0.35% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.36% 0.005% 0.04% 0.001% 0.002% 0.0025% Embodiment 11 0.35% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.36% 0.005% 0.04% 0.001% 0.002% 0.0025% Comparative Example 1 0.15% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.25% 0.005% 0.01% 0.001% 0.002% 0.0025% Comparative Example 2 0.65% 0.15% 16.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.6% 0.005% 0.04% 0.001% 0.002% 0.0025% Comparative Example 3 0.35% 0.15% 12.5% 0.53% 0.015% 0.65% 0.11% 0.05% 0.05% 0.72% 0.6% 0.005% 0.04% 0.001% 0.002% 0.0025%

[0066] Table 2 Process parameters of Examples 1 to 11 and Comparative Examples 1 to 3

[0067] In Table 2, V in the first annealing step 1加热 Denote the heating rate of the first heating step, T 1加热 is the end point temperature in the first heating step, t1 is the holding time in the first holding step, V 1冷却 Denote the cooling rate of the first cooling step, T 1冷却 Expressed as the endpoint temperature in the first cooling step; V in the second annealing step 2加热 Denote the heating rate of the second heating step, T 2加热 is the end point temperature in the second heating step, t2 is the holding time in the second holding step, V 2冷却 Denote the cooling rate of the second cooling step, T 2冷却 Expressed as the endpoint temperature in the second cooling step; V in the heat treatment process 正火 is the heating rate of the normalizing step, T 正火 Expressed as the end temperature of the normalizing step, V 1淬火 Denote the heating rate of the first quenching step, T 1淬火 Expressed as the end point temperature in the first quenching step, V 3冷却 Denote the cooling rate of the third cooling step, T 3冷却 Denoted as the end point temperature in the third cooling step, T 回火 It is represented as the end point temperature of the tempering step, and ttempering is represented as the holding time of the tempering step.

[0068] Test Section (1) Mechanical properties test According to GB / T228.1-2010 “Tensile test of metallic materials Part 1 Room temperature test method”, samples were prepared for the steel plates prepared in Examples 1 to 11 and Comparative Examples 1 to 3.

[0069] The tensile test was carried out using a German Zwick tensile testing machine with a load range of 50kN~1500kN, with a displacement speed of 3mm / min. The tensile strength, yield limit, elongation and other test data of the samples were obtained through computer imaging.

[0070] The impact energy of the steel plate at -50°C was tested in the longitudinal direction D (vertical to the width of the steel plate) for three times and the average value was calculated to obtain the test result value. The test results are shown in Table 3.

[0071] (2) Hardness test The hardness test was performed on the steel plates prepared in Examples 1 to 11 and Comparative Examples 1 to 3 according to the method of GB / T231.1-2018 (Brinell hardness test standard). The test results are shown in Table 3.

[0072] (3) Corrosion resistance test The corrosion performance of the steel plates prepared in Examples 1 to 11 and Comparative Examples 1 to 3 was tested by a neutral salt spray test method, and the results are shown in Table 3. Table 3 Test results of embodiments and comparative examples Serial number <![CDATA[R eL ]]> <![CDATA[R M ]]> A（%） Impact energy Brinell hardness Self-corrosion potential (mV) Example 1 425MPa 526MPa 41% 90J 540HB -624 Example 2 410MPa 501MPa 38% 85J 562HB -612 Example 3 398MPa 489MPa 35% 82J 581HB -604 Example 4 435MPa 542MPa 44% 93J 523HB -631 Example 5 441MPa 554MPa 46% 95J 514HB -599 Example 6 437MPa 546MPa 45% 94J 521HB -608 Example 7 388MPa 456MPa 31% 64J 461HB -652 Example 8 443MPa 551MPa 43% 92J 531HB -615 Example 9 447MPa 553MPa 44% 93J 542HB -609 Example 10 440MPa 541MPa 42% 91J 539HB -610 Embodiment 11 438MPa 542MPa 40% 89J 535HB -612 Comparative Example 1 403MPa 483MPa 29% 53J 328HB -724 Comparative Example 2 381MPa 397MPa 23% 45J 304HB -601 Comparative Example 3 376MPa 408MPa 27% 49J 321HB -635

[0073] Note: R eL Expressed as tensile strength, R M is expressed as yield strength, A is expressed as elongation, where R eL , R M The larger the values ​​of , A and impact energy, the better the processing performance of the steel plate; The larger the Brinell hardness value, the higher the wear resistance; The self-corrosion potential is the metal potential measured in the corrosion system without an applied current. The smaller the absolute value of the negative self-corrosion potential, the lower the corrosion tendency.

[0074] According to Table 3, by comparing the test results of Examples 1 to 11 and Comparative Examples 1 to 3, it can be seen that through the composition control and optimized process of the present invention, the prepared stainless steel composite plate has not only wear resistance but also excellent properties such as good processing performance.

[0075] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit them; although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be included in the scope of the claims and specification of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in each embodiment can be combined in any way. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A method for preparing a high-hardness and wear-resistant stainless steel composite plate, characterized in that: include: A steel billet is provided, wherein the composition of the steel billet is, by mass percentage, C: 0.2% to 0.55%, Mn: 0.1% to 0.4%, Cr: 12.0% to 15.0%, Si: 0.4% to 0.8%, B: 0.005% to 0.02%, Ni: 0.5% to 0.8%, Cu: 0.05% to 0.2%, Nb: 0.01% to 0.1%, Al: 0.01% to 0.1%, Mo: 0.5% to 1.0%, W: 0.3% to 0.9%, Ca: 0.001% to 0.01%, Y: 0.02% to 0.08%, P: ≤0.003%, S: ≤0.004%, N: ≤0.0035%, and the balance is Fe and other inevitable impurity elements; A hot rolling process is to hot-roll the steel billet to obtain a hot-rolled steel plate; A first annealing step, heating the hot-rolled steel plate to a temperature range of 600°C to 880°C at a heating rate of 50°C / s to 80°C / s for a first annealing treatment; A cold rolling process, cold rolling the steel sheet after the first annealing treatment to obtain a cold rolled steel sheet; A second annealing process, heating the cold-rolled steel sheet to a temperature range of 600°C to 750°C at a heating rate of 30°C / s to 40°C / s for a second annealing treatment; The heat treatment step is to heat treat the steel plate after the second annealing treatment to obtain a stainless steel composite plate.

2. The preparation method according to claim 1, characterized in that: The hot rolling process comprises: A rough rolling step, wherein the steel billet is subjected to rough rolling treatment, wherein the starting rolling temperature of the rough rolling is 1150° C. to 1300° C., and the finishing rolling temperature of the rough rolling is 950° C. to 1080° C.; A finishing rolling step, performing finishing rolling on the steel plate after rough rolling, wherein the starting rolling temperature of the finishing rolling is 850° C. to 920° C., and the final rolling temperature of the finishing rolling is 800° C. to 840° C.; In the coiling step, the finish-rolled steel sheet is cooled to below 500°C at a cooling rate of 100°C / s to 150°C / s, and the hot-rolled steel sheet is obtained by coiling.

3. The preparation method according to claim 2, characterized in that: In the finishing rolling step, the finishing rolling reduction rate is 85% to 95%.

4. The preparation method according to claim 2, characterized in that: The first annealing process comprises: The first heating step is to heat the hot-rolled steel plate to a temperature range of 600°C to 880°C at a heating rate of 50°C / s to 80°C / s; The first heat preservation step is to keep the hot-rolled steel plate in a temperature range of 600° C. to 880° C. for 5 h to 36 h; The first cooling step is to cool the hot-rolled steel plate after the first heat preservation step to below 400° C. at a cooling rate of 10° C. / s to 30° C. / s.

5. The preparation method according to claim 1, characterized in that: The reduction ratio in the cold rolling process is 40% to 60%.

6. The preparation method according to claim 1, characterized in that: The second annealing process comprises: The second heating step is to heat the cold-rolled steel sheet to a temperature range of 600°C to 750°C at a heating rate of 30°C / s to 40°C / s; The second heat preservation step is to keep the cold-rolled steel plate in a temperature range of 600° C. to 750° C. for 2 h to 12 h; The second cooling step is to cool the cold-rolled steel sheet after the second heat preservation step to below 350° C. at a cooling rate of 5° C. / s to 15° C. / s.

7. The preparation method according to claim 1, characterized in that: The heat treatment process comprises: Normalizing step: heating the steel plate in the second annealing process to 900°C~1000°C at a heating rate of 90°C / s~110°C / s and keeping it at that temperature for 1h~2h before cooling.

8. The preparation method according to claim 7, characterized in that: The heat treatment process also includes: a quenching step, heating the steel plate after the normalizing step to 700° C. to 850° C. and keeping the temperature for 30 min to 60 min, and then cooling the steel plate to below 250° C. at a cooling rate of 10° C. / s to 50° C. / s for quenching; In the tempering step, the steel plate after the quenching step is heated to 200°C to 300°C and kept at this temperature for 20min to 40min, and then cooled to room temperature at a cooling rate of 30°C / s to 70°C / s for tempering to obtain a stainless steel composite plate.

9. The preparation method according to claim 8, characterized in that: The quenching step comprises: In a first quenching step, the steel plate after the normalizing step is heated to 400°C to 600°C at a heating rate of 60°C / s to 80°C / s and kept at that temperature for 30min to 60min; The third cooling step is to cool the steel plate after the first quenching step to below 250° C. at a cooling rate of 20° C. / s to 40° C. / s.

10. The preparation method according to claim 1, characterized in that: In the steel billet, the contents of C, N, Si, Cr, W and B satisfy 13.5%≤C+N+Si+Cr+W+B≤16.5%.

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