INFLUENCE OF PROCESS ROUTES IN ENHANCING GRAIN REFINEMENT OF AA5052 ALLOY BY EQUAL CHANNEL ANGULAR PRESSING

In this experimental investigation, a pre-processed AA5052 aluminium alloy was subjected to ECAP process at room temperature. It has been subjected to two different processing routes such as RBC and RC. The cut samples of AA5052 alloy was subjected to pre-annealing treatment at 420ºC for an hour prior to the ECAP process. In order to evaluate the influence of different processing routes, the ECAPed AA5052 alloy was investigated for its enhanced mechanical properties and improved microstructure. The hardness of the ECAPed alloy measuring an improved value than the base alloy, where a maximum value of 120 HV was achieved by route RBC. The tensile test also indicates a strong influence of ECAP process in structural refinement. A maximum tensile strength of 386 MPa was found to be in the processed route RBC. The microstructural evolution of base alloy and ECAP processed alloys were characterized using optical microscope. The optical microstructure reveals a refined equiaxed elongated grains in the processed alloy with an average grain size of 13 µm compared with 25 µm of base AA5052 alloy. The experimental results revealed a significant improvement in grain size refinement, yield tensile strength, ultimate tensile strength and hardness of processed alloy as compared with the base alloy of AA5052 aluminium material.