| Title |
Microstructures and Properties of MoSi2 Compound and MoSi2 / Nb Composite by MA-Spark Plasma Sintering |
| Authors |
박용호(Yong Ho Park) ; 정해용(Hae Yong Jeong) ; 이성열(Sung Yul Lee) ; 주영한(Yeong Han Joo) ; 배차헌(Cha Hurn Bae) |
| Abstract |
MoSi₂ is one of the most promising candiate for high-temperature structural materials because of its high melting point and excellent oxidation resistance. However, the low room temperature fracture toughness and ductillity, etc. of MoSi₂ still remains as major obstacles to potential high temperature structural applications. The fracture toughness of brittle matrix ran be improved by the incoporation of a ductile second phase such as metallic Nb. The purpose of this study is to improve the room temperature fracture toughness and ductillity of sintered MoSi₂ and MoSi₂/Nb composites respectively by densification, refining of microstructure and minimizing of interfacial reactions between matrix and Nb. These compound and composite are prepared by mechanical alloying(MA)-spark plasma sintering process(SPS). The microstructures and material properties of these sapmle were investigated by optical microscopy, SEM, XRD, EPMA, microhardness measurement and 4-point bending test. The Vickers hardness, bending strength and fracture toughness increased with the incorporation of metallic Nb. |