Microstructure, mechanical and physical characteristics analysis of ADC14 hypereutectic AlSi composite reinforced with Al2O3

The instigation of primary and eutectic Si has been observed due to the higher content of Si during melting and caused to reduction in the mechanical strength of hypereutectic AlSi alloy. The appropriate mechanism of microstructure and inclusion of strengthening materials can overcome this problem. Thus, in this research work, 5, 10 and 15 wt% of alumina were added in ADC14 hypereutectic AlSi alloy for composite fabrication through stir casting. The microstructure, mechanical and physical characteristics of the AC14 composite were investigated, and the surface response and ANOVA approaches were used to investigate the interaction between variables and responses, and significance of contribution through statistical analysis. The addition of alumina provided better microstructure, and due to it mechanical strengths were improved. The highest value of tensile strength and hardness 85 MPa and 44 VHN respectively were obtained for 15 wt% of alumina. Whereas, the calculated porosity has inverse proportion with the content of alumina. The surface response analysis and ANOVA results showed good interaction between variables and responses, and the contributions were significant. Based on the obtained experimental and statistical results, the addition of alumina provided better mechanical properties and microstructure of the ADC14 composites.