Investigation the effect of B4C addition on properties of TZM alloy prepared by spark plasma sintering

• Pre-alloyed TZM powders with addition of B4C were sintered by using spark plasma sintering (SPS).
• Formation of possible phases during sintering was calculated by FactSage© software.
• Mo2B phase was formed as result of reaction between Mo and B4C during sintering process
• Oxidation resistance and hardness of TZM alloy were enhanced by formation of Mo2B phase in the structure.

TZM alloy is one of the most important molybdenum (Mo) based alloy which has a nominal composition containing 0.5–0.8 wt.% titanium (Ti), 0.08–0.1 wt.% zirconium (Zr) and 0.016–0.02 wt.% carbon (C). It is a possible candidate for high temperature applications in a variety of industries. However, the rapid oxidation of TZM alloys at high temperature in air is considered to be one of the drawback. In this study, TZM alloys with additions of 0–5 wt.% B4C were prepared by spark plasma sintering (SPS) at 1420 °C utilizing 40 MPa pressure for 5 min under vacuum. The effects of B4C addition on oxidation, densification behavior, microstructure, and mechanical properties were investigated. The TZM alloy with 5 wt.% B4C have exhibited an approximately 66% reduction in mass loss under normal atmospheric conditions in oxidation tests made at 1000 °C for 60 min. And an increase from 1.9 GPa to 7.8 GPa has been determined in hardness of the alloy.