Reinforcement of TiB₂ Nanoparticles in Aluminium Piston Alloys for High Performance at Elevated Temperature

Abstract

Nano-TiB₂ particles produced by in situ approaches were employed to reinforce the Mahle 174 piston alloy. Experimental results showed that, with TiB₂ nanoparticles, the mechanical properties were significantly improved at ambient and elevated temperatures. The ultimate tensile property at room temperature was increased from 250 to 332 MPa. The ultimate tensile property at 300 °C was increased from 121 to 174 MPa, and that at 350 °C was increased from 86 to 116 MPa. The increase was 82 MPa at ambient temperature, 53 MPa at 300 °C and 30 MPa at 350 °C, respectively. The mechanism of property improvement in the nanocomposites is attributed to the well-distributed nanoparticles in Al matrix, thermal stability of TiB₂ at high temperature and the formation of high density of dislocation network in the vicinity of TiB₂/Al interface.