Role of Matrix Microstructure in Governing the Mechanical Behavior and Corrosion Response of Two Magnesium Alloy Metal Matrix Composites

摘要

The microstructure, mechanical properties, and corrosion resistance of two popular magnesium cast alloys, namely Mg-Al-Mn alloy (AM100) and Mg-Zn-Cu alloy (ZC63), and their saffil alumina short-fiber-reinforced composites have been investigated. The results reveal that the mechanical behavior of the magnesium alloy metal matrix composites (Mg-MMCs) was influenced by the nature of the base matrix and the microstructural phases present. The behavior of the composites also depended on the fiber volume fraction. The composites of the two alloys showed an improvement in tensile strength at high temperatures compared with the unreinforced counterpart. Under impact loading and salt spray corrosion conditions, the composites exhibited observable degradation in properties. Under corrosion, the distribution of microstructural phases essentially determined the corrosion resistance of the matrix. The effect of the inherent nature of the alloy matrix in controlling both the mechanical properties and corrosion behavior of the Mg-MMCs is thoroughly discussed.