Analysis Of Roll System Deformation And Heat Treatment Process On Stainless Steel Thin Strip

Stainless steel thin strip is widely used in the construction industry,industrial electrical equipment,automobile manufacturing industry,aerospace and other fields due to its wide variety and excellent characteristic.However,in China,most of the stainless steel enterprises still have a series of difficulties in the production of stainless steel thin strip.For example,the thickness control is not accurate.The shape of the strip is defective and the mechanical property of the strip is insufficient.Based on the shape and property of stainless steel strip,this paper studies the shape and mechanical property of stainless steel thin strip,which provide theoretical guidance for the actual production process.The shape of the strip is closely related to the gap of the work roll.In order to obtain a better strip shape,the elastic deformation of the roll system is analyzed.Through the establishment of the finite element analysis model,under the condition of the specific rolling force exerted by the work roll,the influence of the elastic deformation of the roll system is explored by changing the elastic modulus of the work roll and the taper lengths of the first intermediate roll.Through calculation and analysis,it can be seen that:1.In the process of the first intermediate roll moving,the smaller the elastic modulus of the work roll is,the larger the flattening deformation of the work roll is.The elastic modulus of the work roll can adjust the change of the secondary crown and the fourth crown.With the increase of the elastic modulus,the change of the secondary crown and the fourth crown reduced gradually.The transverse rigidity of the roll system increased,and the change of the strip edge drop reduced.2.The change of the taper length of the first intermediate roll has an obvious effect on the bearing roll gap curve.With the increase of the length of the first intermediate roll,the deflection and convexity of the work roll decrease gradually.The flattening deformation of the work roll in the non taper section of the first intermediate roll increases to a certain extent.The secondary crown and the fourth crown of the bearing roll gap also decrease with the increase of the taper length.In the process of increasing the taper length,there is no obvious change in the transverse rigidity of the roll system.The edge drop of the strip is gradually decreasing.When the length of the first intermediate roll increases to a certain extent,the edge thickening will occur.The excellent comprehensive property of thin strip depends not only on the strict control of shape and thickness,but also on the excellent mechanical property.According to the mechanical property of stainless steel strip,the heat treatment processes of 0Cr17Ni7 Al precipitation hardening stainless steel thin strip were studied under different solution treatment time.The microstructure and properties of the samples under different heat treatment processes were analyzed by XRD,OM,SEM,micro-vicker hardness tester and tensile tester.From the characterization analysis,the hardness of rolled stainless steel strip is only 174.13 HV due to the existence of a large number of residual austenite and ferrite in the raw material.At this time,the plasticity is better.Only adjustment and aging treatment failed to form uniform austenite,which could not completely transform austenite into martensite,resulting in a hardness of only 427.82 HV.Tensile yield strength is only 1067.85 MPa,and tensile strength is 1428.76 MPa.The elongation is 18.13%.After 1050?×(1?2)min solution treatment and water quenching,the carbide and alloy elements are fully dissolved to form austenite with uniform structure.After adjustment treatment and aging treatment,further transformation of austenite to martensite and uniform precipitation of high-density Ni Al nano strengthening phase are realized.The hardness of 0Cr17Ni7 Al stainless steel is up to 510.81?512.74 HV,and the tensile property is the best.The yield strength is 1312?1342 MPa,and the tensile strength is 1455?1478 MPa.The elongation is 11.2?11.6%.With the solution treatment time increase to 3?7 min,the nucleation rate of martensite decreased.The content of retained austenite increased.The hardness and tensile properties of stainless steel decreased.