Fracture Property Correlation of Rheocast (EMS) and Thixocast 6061 Aluminium Alloy

Abstract

The present study has been taken up to establish fracture property correlation of the semi solid processed 6061 aluminium alloy. Electro Magnetic Stirring (EMS) has been performed to get non-dendritic billets and then the alloy has been thixocast using a High pressure die casting machine. Tensile tests have been performed to estimate mechanical properties of the semi solid processed alloy. Fracture behaviour of the alloy has been investigated at the intermediate EMS cast state and subsequent final thixocast state, employing uniaxial tensile tests at 0.001s-1 strain rate and at room temperature. Fracture surface morphology of the EMS cast state shows that the presence of micro porosity is responsible for crack initiation and final fracture. Our results confirm that the dimpled rupture of primary Al phase is responsible for improved mechanical properties in the thixocast state of the alloy