This paper is concerned with the analysis on the surface stress profiles of AISI 1015 steel in backward extrusion process. Heavy surface stress such as surface expansion appeared in backward can extrusion process usually leads to very severe tribologi...
This paper is concerned with the analysis on the surface stress profiles of AISI 1015 steel in backward extrusion process. Heavy surface stress such as surface expansion appeared in backward can extrusion process usually leads to very severe tribological conditions along the interface between workpiece and punch land. In the present study, influence on the punch face angle and reduction has been investigated in terms of the surface stress profiles such as surface expansion, pressure exerted on the tool surface between tool and workpiece, respectively. The main goal of this study is to examine the influence of process conditions such as degree of reduction in area and geometries of punch face on the deformation pattern of the model material in backward extrusion, especially for surface stresses. It is well known that among various surface stresses, surface expansion and contact pressure distribution along the die-workpiece interface are closely related to the condition of lubrication at the interface for both solid and liquid lubricants, and contact pressure and sliding distance between workpiece and tool are essential parameters to evaluate the tool wear. The geometrical parameters employed in analysis include the punch face angle of the punch nose as well as reduction ratio. Extensive simulation has been conducted by applying rigid-plastic finite element method to backward can extrusion process under various geometrical conditions. The simulation results are summarized in terms of surface stresses such as surface expansion, pressure and comparison of surface loads for different process conditions, which constitute of surface stress profiles. It was found from the present study that the surface expansion is more influenced by reductions than the punch nose angle.