Influence of punch shape on drawability of locally solution treated 6061 aluminum alloy sheets

Abstract

The deep drawability of the peripherally softened aluminum alloy blanks was investigated for various punch shapes. The flange parts of the 6061-T6 sheets were locally solution treated and softened using various heated dies. Deep drawing tests of the blanks were examined using a flat and a hemispherical cylinder punches. The limit drawing ratios (LDR) of local solution treated blanks were larger than those of the homogeneous T6 blank for both flat and hemispherical punches. The optimal softened region for a hemispherical punch was larger than that for a flat one. The LDR and the optimal softened region of local solution treated blanks were predictable by the FEM analysis for both hemispherical and flat punches. The optimal softened region of calculations for a hemispherical punch became larger with increasing n value of a central hard part.