Aluminiums for thixoforging and preparatory conditions and parameters necessary before forming: A review

The thixoforging of aluminium alloys has received in recent years an extensive interest for the manufacture of parts because of its advantages. To choose an aluminium alloy as raw material for a thixoforming process, it is important to know, the product characteristics, respectively the expected mechanical properties, and secondly, the semi-solid interval and the temperature of fusion. Various wrought and foundry aluminium alloys are thoroughly summarized in this review paper, together with a description of the evaluation methods for the heating temperature sensitivity. Furthermore, for thixoforging industrial applications, the heating strategy is very important, and the reheating regime should be systematically analysed. The advantages offered by thixoforging of aluminium alloys are associated to the feedstock material microstructure that results after reheating to the semi-solid range, which is key to understand the rheological behaviour and the final mechanical properties of the thixoformed parts. In the future, a process model needs to be developed to integrate microstructure conditioning during reheating of the material to the semi-solid state.