| The high proportion of nickel,chromium,and other precious metals in stainless steel leads to high costs.The development of alternatives to stainless steel has become an important research direction in the field of materials.Stainless steel composite plate not only has the corrosion resistance,wear resistance and antimagnetic performance of stainless steel,but also has good mechanical strength and processing performance of carbon steel,which can perfectly replace stainless steel and is widely used in machinery manufacturing,petrochemical,aerospace,medical equipment,etc.Building decoration and other fields.As a martensitic stainless steel in the four major stainless steel systems,not only the nickel content is small,but some even do not contain nickel,the price is low,mainly used in occasions with good wear resistance and high strength.This paper takes the asynchronous rolling process of 13Cr/Q235 martensitic stainless steel composite plate as the research object,using MSC.MARC finite element analysis software,establishes the asynchronous rolling model of stainless steel composite plate,and studies the deformation behavior of the composite plate after rolling.The asynchronous ratio of rolling,the amount of single-pass reduction and the total reduction were determined.Through the hot rolling experiment in the middle stage,the accuracy of the finite element model was proved,and the feasibility of the preparation of the martensitic stainless steel composite plate was verified.Finally,a qualified 13Cr/Q235 martensitic stainless steel composite plate was prepared under industrial conditions.The specific research content is as follows:Firstly,the asynchronous rolling model of stainless steel composite plate was simplified and established.The thermal conductivity,specific heat capacity,thermal expansion coefficient and Young's modulus of the material were calculated by us ing JmatPro.Single-variable method was adopted to determine the single-pass reduction rate and the best asynchronous ratio of asynchronous rolling in different working conditions according to the deformation behavior of rolling pieces.According to the composite criteria,the total reduction required when the composite sheet reaches full recombination is obtained.Secondly,through the pilot experiments with different reductions,the accuracy of the finite element prediction model was verified.According to the degree of deformation of each layer after the two layers of metal are fully composited,the relationship between the degree of deformation of the stainless steel layer and the degree of deformation of the carbon steel layer is obtained.Afterwards,microstructure observation and mechanical properties tests were performed on the interface of the composites with two reduction ratios.The results show that the conclusions obtained from the pilot rolling experiment and the finite element simulation are si milar,and the finite element prediction model is more accurate;the slope of the composite thickness ratio curve gradually decreases with the progress of rolling,and finally converges to a fixed value after complete compounding;The mechanical properties of the composite plate rolled out by reduction are superior.Finally,under the industrial conditions,the asynchronous rolling experiment of the stainless steel composite plate was conducted.According to the rule of layer-thickness ratio summed up in the middle stage,the initial thickness of each layer of metal was set,and the stainless steel composite plate with the required layer-thickness ratio was successfully rolled.Subsequently,the microstructure and mechanical properties of the stainless steel composite plate under industrial conditions were analyzed.The results show that the tensile strength,shear strength,bending toughness,and impact notch toughness of the stainless steel composite panels under industrial conditions are higher than those of the stainless steel composite panels in the pilot test stage,which is much larger than the national standard. |
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