Experimental investigation on the effect of applied pressure on microstructure and mechanical properties of squeeze cast AC2A aluminium alloy

This investigation focuses on the attempt made to prepare AC2A castings of a non-symmetrical component through squeeze casting process. Samples were produced to study the effect of squeeze pressures (0.1, 25, 50, 75, 100 and 125 MPa) on microstructure and mechanical properties of the alloy. Results of hardness and tensile tests indicated that squeeze cast specimens exhibited higher mechanical properties than gravity die cast specimens. This was mainly due to applied pressure which resulted in effective filling of the melt into die cavity, microstructural refinement and good heat transfer between the melt and the die. Pressure of 50 MPa was found to be sufficient for pore free castings and pressure of 100 MPa was noted for sound castings. From this study, the squeeze casting process is noted to be suitable for processing this alloy.