Comparison of mechanical properties of semi solid forming and hot forming and hot forming of A356 aluminum alloy

Abstract

Thixoforming is a forming technology to produce near net shaped complex partswith high mechanical properties especially for automotive industry. The process is based on a discovery made at MIT in the early 1970s. The operation takes place in the semi solidregion of the metal and therefore has several advantages such as close dimensionaltolerances, lower porosity and better mechanical properties over conventional formingprocesses. In this study origins and principles of thixotropic behavior of metals were explained with giving examples of previous studies on the subject. The productiontechniques for obtaining the necessary raw material with fine and globular microstructurewere explained and the steps of the forming process were described. In the experimentalpart of the study semi-solid forming and hot forming experiments were conducted on A356 aluminum alloy, at different temperatures with various holding times. After the productionof the samples the effects of the heating parameters on the final microstructure of semisolidformed products were examined. Finally microhardness and tensile tests wereperformed on the samples and a comparison of mechanical properties was made betweensemi solid formed and hot formed samples.