Experimental investigation on mechanical and metallurgical characteristics of magnesium metal matrix composites reinforced with hafnium carbide

Abstract

In recent times, a lot of research is being conducted for developing newlinestrong materials. Developments in manufacturing, automobile, power and newlineaerospace sectors require corrosion, wear and fatigue resistant materials newlinewhich can withstand rough and volatile environments. Metal Matrix newlineComposites (MMCs) are being used in many sectors as they exhibit enhanced newlinemechanical and metallurgical characteristics, compared to their parent alloy newlinematerial. Even though a lot of research is being conducted in developing newlinedifferent combinations of MMCs, there is a tremendous scope for newlineimprovement. Magnesium and its alloys are preferred over other materials as newlinethey have low density, high strength, ease of machinability, good thermal newlineconductivity and appreciably good corrosion resistance. At high temperature newlineoperations, creep and wear resistance of Magnesium (Mg) based alloys drops. newlineMMCs prepared using Mg based alloys can withstand external wear and newlinetough environment. The properties of Mg MMCs can be enhanced by using newlinedifferent types of reinforcements such as Carbides, Ceramics, Cermets etc. newlineThe composite preparation process, geometry of the reinforcements and the newlinequantity of reinforcements in MMCs should be chosen properly as they affect newlinethe strength of MMCs. In this research, Mg based MMCs were prepared using stir casting newlineprocess. Three Mg based alloys such as AZ31 Mg, ZE41 Mg and AZ91 Mg newlinewere selected to be the matrix material. AZ31 Mg material is a wrought alloy newlineexhibiting excellent strength, ductility, formability and machinability at room newlinetemperature. ZE41 Mg is a casting alloy comprising of zirconium and rare newlineearth materials. ZE 41 Mg alloy exhibits excellent weldability and castability. newlineAZ91 Mg alloy is a light weight material containing Al. AZ91 Mg alloy newlineexhibits excellent corrosion resistance and high strength. Hafnium Carbide newline(HfC), a hard refractory material, was used as reinforcements. HfC exhibits newlinecubic crystal structure and has very high melting and boiling point. Using stir newlinecasting process, HfC reinforced Mg MMCs were prepar