Semisolid Forging of 7000 Series Aluminum Alloys

The achievement of lighter automotive components is an important driving force in the development and optimization of casting techniques. In this sense, semisolid forming is an emerging technology that has allowed the production of security components using aluminum alloys. The foundry alloys A356 and A357 remain, up to the present, the most used alloys for the semisolid processing of components. Nevertheless, several authors have pointed out the gain in properties that other alloy families could provide. In the present work, thixoformability of 7000 series aluminum alloys is studied. Thermodynamic calculations (CALPHAD method) and calorimetric experiments have been performed to determine the composition of alloys with an optimum process window. A modification of the 7075 alloy is proposed in order to improve its thixoformability parameters and optimize the process control. A simple component has been produced by semisolid forging and mechanical properties have been measured from tensile samples.