MICROSTRUCTURAL CONTROL THROUGH SOLIDIFICATION PROCESSING OF MULTIPHASE Mo-SILICIDE ALLOYS


Professor David Johnson
School of Materials Engineering
Funding: Oak Ridge National Laboratory

Recent research has identified multiphase alloys in the Mo-Si-B system as possible candidates for high temperature structural applications. These alloys consists of a Mo-rich bcc solid solution, the compound Mo5SiB2 (T2), and other transition metal silicides. A balance of toughness, oxidation resistance and creep resistance is sought from this mixture of metal and silicide phases. The possibility of improving the mechanical properties and oxidation resistance by refining the microstructure through eutectic solidification is being examined. Changes in eutectic morphologies due to quaternary additions to Mo-Si-B system are being investigate in terms of solidification science and the fracture behavior of bulk size castings.