Abstract
The severe plastic deformation (SPD) technique called large strain extrusion machining (LSEM) is being increasingly being used to fabricate bulk nanostructured materials. During LSEM, the morphology (microstructure) and physical/mechanical properties of the deformed chip depend on the amount of strain induced during processing. It is therefore critical to understand the mechanism and process of workpiece deformation and the correlation between the deformation and machining parameters has also been studied. The current study attempts to understand the influence of constraining tool corner radius (R) on the deformation behavior in LSEM. Finite element analysis (FEA) has been presented in this article to understand the relationship between strain and strain rate and changes in constraining tool corner radii. FEA results show different effective strains that can be produced during LSEM by changing the constraining tool corner radius, and thus the micro and nanostructure of the resulting bulk material can be controlled. Samples have also been fabricated by LSEM using various tool corner radii and their microstructures have been characterized.