On the deformation and fracture behaviour of low-pressure gas (LPG) grade steel and two aluminium alloys

Material properties influence the behaviour during the processing of a sheet metal to a final product. Metallurgical defects in the form of inclusions as well as the presence of phenomena that aid strain localisation, limit the ductility of the material. This paper illustrates the deleterious effects on formability of inclusions in an LPG steel and Dynamic Strain Ageing (DSA) in an aluminium alloy. Two heats of LPG steel were studied with reference to their deformation and fracture behaviour. On similar lines, investigations on two alloys of aluminium, namely, an Al-Cu-Mg alloy (which displays dynamic strain ageing at room temperature) and an Al-Mn alloy (which shows no DSA) were carried out. It was observed that the formability assessed in terms of the Forming Limit Diagram (FLD) was consistent with the conclusions drawn from other studies. © 1993.