Influence of ZrB۲/SiC Hybrid Particles on Microstructure and Creep Resistance of AZ۳۱Magnesium Alloy Matrix Composite

Magnesium alloys have been attractive to engineers due to their high strength-to-weight ratio, leading to their widespread use in recent years. However, their poor creep resistance, particularly at high temperatures, has limited their applications. Reinforcing the magnesium matrix with ceramic particles could significantly improve creep properties. In this research, ZrB۲ and SiC microparticles were separately milled for ۶ hours at ۳۵۰ rpm under an argon atmosphere, and powders were mixed and milled for ۲ hours at the same condition to achieve a homogeneous hybrid powder. The hybrid particles were added to the AZ۳۱ magnesium alloy in various amounts via the stir-casting method, to produce hybridcomposites. The microstructure of specimens has been characterized using optical microscopy (OM), scanning electron microscopy (SEM), X-ray analysis (XRD), and energy-dispersive X-ray spectroscopy (EDX). The results indicated that the AZ۳۱/۱.۵vol% ZrB۲-۰.۵vol% SiC hybridcomposite possessed the finest grains with uniform distribution of reinforcements and the intermetallic β-Mg۱۷Al۱۲ phase. Hardness and creep tests were performed to evaluate the creep resistance of the hybridcomposites. While AZ۳۱/۲vol% SiC showed the highest hardness, the AZ۳۱/۱.۵vol% ZrB۲-۰.۵vol% SiC hybridcomposite demonstrated the best creep behavior.

کلیدواژه ها:

AZ۳۱Magnesium Alloy ، SIC ، ZrB۲ ، Hybrid composite ، Creep resistance