Effect of micron-Ti particles on microstructure and mechanical properties of Mg–3Al–1Zn based composites

In the field of metal matrix composites, it is a great challenge to simultaneously improve the strength, ductility and elastic modulus of magnesium matrix composites (MMCs). In this work, Mg–3Al–1Zn composites reinforced with micron-Ti particles were prepared by powder metallurgy. The results show that the yield strength, elongation and elastic modulus simultaneously were increased with increasing content of Ti particles. Through diffusion, Ti and Al formed TiAl phase at the edge of Ti particle. A nanoscale layer of MgO formed between TiAl and magnesium (Mg) matrix. The 9Ti/Mg–3Al–1Zn composite obtained the best comprehensive mechanical properties with yield strength, ultimate tensile strength and elongation of 264 MPa, 294 MPa and 8%, respectively. The increased strength is mainly due to the grain refinement and strong interfacial bonding between Ti particles and Mg matrix. The improved ductility is the result of refined grains, weakened texture and collaborative deformation of Ti particles.