Synthesis of Mo-Si-B in situ composites by mechanical alloying

In this study, the synthesis of Mo-Si-B multi-phase alloys, so-called in situ composites, was attempted with the combination of mechanical alloying (MA) and spark plasma sintering (SPS) processes. MA was conducted with mixed powders of Mo, Si and B using a planetary ball mill under various milling conditions. MAed powders were characterized by X-ray diffractometry (XRD) and scanning electron microscopy (SEM). The results obtained by XRD indicated that Mo-Si-B alloyed powders were successfully produced when elemental powders were milled at a higher milling energy. Vacuum heat treatments after the MA process promoted the formation of Mo-Si-B intermetallic phase in MAed powders. MAed powders were successfully consolidated by SPS and sound compacts Of Mo5SiB2-based composites were synthesized. (C) 2006 Elsevier B.V. All rights reserved.