Investigation of Strain Hardening in Aluminum Alloy Sheared Sheet Based on Microhardness Measurement and FEM Analysis

Abstract

This research was carried out to investigate the strain hardening in an aluminum alloy worksheet caused by punch/die shearing by means of microhardness measurement and finite element method (FEM) analysis. To examine the strain-hardened zone at the sheared edge of a worksheet, a 0.36 mm thick AA4047 aluminum alloy cut by punch/die shearing was subjected to microhardness measurements. In addition, a two-dimensional FEM model was developed and used to simulate the shear cutting of the aluminum alloy worksheet. The fundamental shear cutting parameters, punch/die clearance, cutting tool wear, and friction at the worksheet/tool interfaces were numerically varied and simulated. From the investigation results, the strain-hardened zone was observed by hardness measurement. The size of the zone significantly varied under different cutting parameters. From the simulated stresses at the sheared zone, the variation of the width of the strain-hardened zone with respect to cutting parameters was determined by the maximum principal stress on the worksheet being sheared.