Preparation of in situ TiCP/LY12 composite and its microstructure and mechanical properties

Mechanical properties of TiCP/LY12 Al-based composites prepared by an in situ synthesis method were studied. The micro-structure, morphology, and distribution of TiCp particles in the LY12 Al alloy matrix were also investigated by XRD, SEM, and HRTEM. The phase composition of the TiCP/LY12 composites, interfacial structure of TiC particle-to-particle and TiC particle-to-Al matrix, and structure of triple phase among TiC particle, Al2Cu phase, and Al matrix were also studied. There are no detectable Al3Ti phases in TiCP/LY12 composites, and a strong cohesive interface between TiC particles and Al-based alloy matrix was observed in the in situ synthesized TiCP/LY12 composites. After heat treatment using T6 procedure, it was found that ultimate strength (σb), yield strength (σs), and Young's modulus (E) of TiCP/LY12 composites increased but the elongation ratio decreased with increasing of the mass fraction of TiC particles.