EXPERIMENTAL INVESTIGATION INTO THE EFFECT OF COLD ROLLING ON FRACTURE TOUGHNESS AND MECHANICAL PROPERTIES OF AA5754 H111 ALUMINIUM ALLOY

The paper deals with the experimental examination in to fracture toughness and mechanical behaviour of an AA5754 H111 aluminium alloy sheet during cold ro lling reduction. The fracture toughness parameter J0.2 of the AA5754 H111 aluminium alloy before and after cold ro lling was estimated by conducting a ducti le tearing test using centre-cracked panel (CCP) specimens along two directions, ro lling direction (RD) and transversal direction (TD). The conventional tensi le tests in two directions and microhardness tests were also used to investigate mechanical properties of unro lled and ro lled AA5754 H111 aluminium alloy. The findings revea led a significant effect of cold ro lling on the fracture toughness parameter and the mechanical properties of the AA5754 H111 aluminium alloy along the RD and TD. A fast increase in strength and hardness and a sharp drop in the fracture toughness parameter J0.2 and ducti lity were recorded with a rise in the amount of cold rolling reduction. The greatest strength was obtained along the RD and the highest ducti lity was found along the TD.