In situ synthesis and compressive deformation behaviors Of TiC reinforced magnesium matrix composites

Abstract

TiC reinforced magnesium matrix composites (Mg-MMCs) were successfully synthesized by spontaneously infiltrating the molten magnesium into Ti-C preforms, simultaneously in situ forming TiC particles in the liquid of magnesium alloy. The compressive deformation behaviors of TiC reinforced Mg-MMCs were further investigated by means of uniaxial compression tests at strain rates between 10-3 s-1 and 1 s-1 and temperature between room temperature and 200°C. Early fracture was observed in the low-temperature/high strain rate regime, fracture occurring by crack propagation at 45 degree with respect to the compression axis. In high-temperature/low strain rate regime, the flow curves exhibited the typical flow softening shape. The results show that with the addition of TiC particles Mg-MMCs can effectively improve compressive properties of magnesium matrix at testing temperature interval. When compared to the unreinforced counterpart, TiC reinforced Mg-MMCs need higher temperature and lower strain rate to avoid premature fracture. © 2008 The Japan Institute of Metals.