A rigid-plastic finite element analysis of temper rolling process

Abstract

A study on temper rolling process has been carried out using rigid-plastic finite element method. Rigid-plastic formulation can be used to predict the roll force and roll torque and to study the deformation field of the rolled sheet. Hitchcock’s formula for roll deformation does not consider the effect of frictional traction on the roll deformation. Hence, to account for high friction present in temper rolling, the roll deformation is computed in an iterative manner using theory of elasticity solution considering roll as an elastic half space. The study reveals that some of the assumptions made for approximate theory of temper rolling are not valid. The deformation field consists of a central rigid (actually elastic) zone and is highly non-homogeneous across the thickness of the strip. Longitudinal stress is not uniform across the thickness of the sheet, hence one-dimensional analysis of the process does not seem to be appropriate. Whereas a rigorous analysis is possible using elasto-plastic finite element formulation at the expense of large amount of computational time, a study using rigid-plastic formulation may be used to understand the qualitative effects of process parameters.