Tribo-mechanical behavior of complex hypereutectic Al–Si alloy compressed through a converging die at elevated temperatures

Abstract

This work deals with the tribo-mechanical behavior of the complex hypereutectic aluminum-silicon alloy Al–18Si–2.5Cu–0.6Fe (wt%) in the as-cast condition and the following compression through converging die under different reduction ratios (R) of 1.5 and 2.0 at working temperatures of 300, 400, and 500 °C. X-ray diffractometry pattern showed the formation of intermetallic compounds (β-Al4.5FeSi and Al2Cu) due to the higher temperature during the process run over. Microstructural features were characterized by scanning electron microscope, and remarkable grain refinement was observed in the compressed samples. Mechanical properties were adjudged by tensile test and microhardness test. There was significant improvement in the ultimate tensile strength and hardness of the compressed billets which may be attributed to grain refinement of the matrix and uniform dispersion of the fine Si particles and the intermetallic compounds. A pin-on-disc tribometer was used for the wear test. Higher wear resistance was observed in the compressed alloy as compared to the as-cast alloy due to the presence of the fine Si particles and strengthening of the matrix. The present work provides valuable insights into tribo-mechanical characteristics of the Al–18Si–2.5Cu–0.6Fe (wt%) alloy for broad industrial applications.