Effect of Oxygen Content in Powders on Microstructure and Mechanical Properties of WC-FeAl Composites Fabricated by Vacuum Sintering Technique

摘要

WC-FeAl composites were fabricated by vacuum sintering technique from mixture of WC and FeAl powders containing various oxygen content. Mechanical properties such as hardness, fracture toughness and transverse rupture strength were influenced by the oxygen content in the powders. Control of the oxygen content was succeeded by changing the powder preparation process. Contrary to expectations, the reduction of oxygen content led to degrade the fracture toughness and transverse rupture strength of the composites. This result was attributed to the microstructural change in the sintered composite. The sintered composite of lower oxygen content exhibited WC grain growth or inhomogeneous microstructure, which can be the cause of degradation of those mechanical properties. It was concluded that the oxygen content was one of the key factors to influence the microstructure or mechanical properties of WC-FeAl composites.