Effect of Ti addition on density and microstructure development of MoSiBTiC alloy. Issue 1760 (12th January 2015) - Baker, I.
ABSTRACT The effect of Ti addition on the density and microstructure development of MoSiBTiC alloy was investigated. Two kinds of MoSiBTiC alloys with the composition of Mo-5Si-10B-10Ti-10C (10Ti alloy) and Mo-5Si-10B-15Ti-10C (15Ti alloy) (at. %) were prepared by conventional arc-melting. The primary phase of as-cast 10Ti and 15Ti alloys was (Ti, Mo)C, and there were two eutectic phases of Moss + (Ti, Mo)C and Moss + T2 + (Ti, Mo)C in the alloys. In addition, 10Ti alloy had a Moss + T2 + (Mo, Ti)2C eutectic. There was no Moss + T2 + (Mo, Ti)2C eutectic in the 15Ti alloy, and thus it is apparent that the (Mo, Ti)2C formation was suppressed by 5 at. % Ti addition. The volume fraction of (Ti, Mo)C increased and thus the density reduced from 8.78 to 8.43 g/cm3 with the Ti addition. In all constituent phases, Ti concentration increased while Mo concentration decreased. In spite of the changes, hardness, Youngâ€™s modulus and shear modulus were hardly changed. Therefore, Ti addition seems to be effective to further lower the density without deteriorating mechanical properties of the MoSiBTiC alloy.