Estudo do deslizamento avante na laminação a frio do aço inoxidável AISI 430 e sua influência no acabamento superficial

Abstract

For most applications, AISI 430 stainless steel requires a high degree of surface quality. To avoid scratches on the strip surface during cold rolling in a Sendzimir mill, estimated values of forward and backward slip are required to synchronize the speed of the driven deflector rolls. Forward slip is also an important variable to prevent skidding during rolling and an investigation of its behavior is presented in this work. A comparison of analytical and numerical models of the rolling friction hill was performed to determine the most appropriate model to investigate the mean friction coefficient and forward slip in the cold rolling of AISI 430 stainless steel produced at Aperam South America. The finite element method was employed in the computational simulations using the Abaqus program. The flow curve of the AISI 430 steel used in the analyses was obtained by two different methods, and the evolution of the strip surface during rolling in the laboratory was analyzed. To investigate the typical friction coefficient of the industrial cold rolling process, data from 60 coils were implemented in the analytical model to statistically validate the results. Furthermore, the relationship of the forward slip variable with events that compromise the surface quality of AISI 430 steel during rolling is discussed, such as the occurrence of skidding, generation of thermal scratches and mechanical scratches due to poor synchronization of the deflector rolls and the strip. The study allowed to identify the most appropriate mathematical model for simulating the cold rolling process of AISI 430 steel in a Sendzimir industrial rolling mill. The findings of this work will allow to improve the prediction of forward slip and will contribute to investigate the influence of this variable on the surface quality of cold rolled AISI 430 steel.