Comparative Analysis of Mechanical Properties of Aluminium Silicon Alloy Produced by Sand Casting and Die Casting

In this work, selected mechanical properties such as tensile strength, hardness and microstructure analysis of a sand cast and die cast of aluminum silicon alloy was investigated and compared. An aluminum silicon alloy was cast using sand mould material and die mould material. The cast produced from both methods were subjected to tensile test, hardness test and microstructure analysis test. The die Al-Si cast has the hardness test of 134.5 HV while sand Al-Si 131, 9 HV. The die AL-Si cast has the yield point stress of 118 N/m2 and sand cast was 105 N/m2. The microstructure analysis result showed the particle of AL-Si cast produced by die cast is more refined than the sand Al-Si cast. The hypoeutectic alloy shows a mixture structure of α –phase and fine eutectic phase of α +Si, though the hypereutectic alloys show a mixture of fine eutectic phase of α+Si and Si particles phase in which the size of particles increases with increasing silicon concentration of the alloy. The degree of refinement of the eutectic silicon increased as the silicon content of the alloy increased beyond the eutectic composition. Here, the primary silicon appears as coarse polyhedral particles. Conclusively die casting produced better Al-Si alloy than sand casting method.