Influence of Reheating Temperature and Time in Thixoforging Process on Microstructure and Mechanical Properties of Aluminum A356 Flange

In this research، a thixoforging process is studied as one of the semi-solid forming processes that include aluminum alloy forging in two-phase temperature range (between solidus and liquidus). For this purpose and in order to achieve favorable conditions in the two-phase zone، the influence of reheating temperature and holding time on thixoforging process is investigated. Semi-solid temperature and holding time are considered 580، 590، 600 °C and 5، 10، 15 minutes respectively. Attained results show that the finest microstructure (73 micrometer) is obtained in semi-solid temperature of 600°C and holding time of 5 minutes. Also، the hardness and the compressive test are performed in order to find the best mechanical properties. As it is expected، the best mechanical properties (yield stress of 149 MPa، ultimate compressive stress of 433 MPa and hardness of 79 VHN) are achieved in sample with the finest structure.