Analysis And Optimization Of Tandem Cold Rolling Process For Ferritic Stainless Steel Strip

Ferritic stainless steel plays an important role in the stainless steel family since it does not contain precious alloying element nickel,and the cold-rolled and annealed strip of which accounts for an increasing proportion in industrial production.As a main production way of ferritic stainless steel,the tandem cold rolling has a high efficiency and high yield production.What are the differences in deformation,microstructure and property of cold rolled and annealed strip existing between the tandem rolling process and the reciprocating rolling one? How to improve the microstructure of the strip by adjusting the pass reduction rate? To answer the questions requires an in-depth study.In this paper,the elastic-plastic finite element method is used to analyze the shear strain in ferritic stainless steel strips in the tandem rolling process and the reciprocating rolling one.At the same time,the microstructure and property of the cold rolled and annealed strips in the two rolling processes were compared.The pass reduction rate of tandem cold rolling is optimized based on shear deformation.The specific research contents are as follows:(1)The true stress-strain curves of SUS436 L ferritic stainless steel were obtained by experiments,and the deformation resistance model was constructed.The finite element model for shear deformation analysis of strips was established based on elastoplastic finite element method,and the model is optimized by comparing the rolling forces calculated by the model to the ones tested in practical rolling processes.(2)With the same total reduction rate,the shear strain of the cold rolled strips,and the microstructure,the properties,the corrosion resistance of the cold rolled and annealed strips in the tandem cold rolling process and in the reciprocating rolling one were analyzed and compared.(3)The shear deformation of the cold rolled strip with different pass reduction rate and the same total reduction rate was analyzed in tandem rolling process.And the pass reduction rate distribution was optimized based on shear strain energy density calculation.