Synthesis and Characterization of Zn-Al2O3Composite

Abstract

In this thesis, comparative study of zinc and zinc/alumina composite is done. Fabrication of Zinc-Alumina metal matrix composite is done by in-situ reaction and direct blending of Zn with alumina was investigated. In in-situ process ZnO and Al were mixed and heated at 500oC to produce two composites, Zn-48.45 vol. % Al2O3 and Zn-60 vol. % Al2O3. The same compositions were also developed by direct reaction. The composite developed was characterized using x-Ray diffraction, scan-ning electron microscope (SEM), hardness measurement using Vickers hardness tester, thermal property analysis and wear testing. Microstructural study of fractured samples were also done. The results show that reaction of ZnO and Al led to the dis-placement reaction to produce Al2O3 in small proportions. The reaction product microstructure also consist some nano-sized particles. Although the preparation of the composite by direct reaction does not show any sign of formation of nano-sized alumina. The wear properties and hardness value of composites are greatly superior than that of Zn metal. In fracture analysis of the composite it was observed that frac-ture surface is covered with alumina particles.