Microstructures and Mechanical Properties of TiB₂-SUS316L Cermets Prepared by Pressureless Sintering

Abstract

The densification behaviour of different TiB₂ powders sizes of TiB₂-(3-25vol%)Stainless steel (SUS316L) cermets was examined during pressureless sintering in argon atmosphere. Microstructures of sintered cermets and mechanical properties such as Vickers hardness, bending strength, fracture toughness and Young's modulus were also investigated. When fine TiB₂ powders were used, TiB₂-SUS cermets with good sinterability and enhanced meccanical properties could be produced. Full density sintered cermets were obtained, and a new phase, Fe2B, was observed in 5-15vol%SUS cermets. The highest hardness values of 21GPa and the Young's modulus of 498GPa were obtained at 5vol%SUS. The highest bending strength of 1290MPa, was obtained for the 15vol%SUS cennet. Iron besides and titaniume oxides in sintered cemrets are connected with the presence of B, O impurities in TiB₂ powders. In cider to improve mechnical properties, finer powders with low oxygen and carbon content, are desirable.