Effect of consolidation and oxide dispersoid addition on phase formation and mechanical properties of WTi ODS alloy

• Oxidation of WTi alloy can be significantly reduced by SPS technique.
• (W,Ti)C solid solution caused by carbon contamination during SPS
• α″ martensite formed by rapid cooling, strain or contamination during process.
• The presence of (W,Ti)C and α″ martensite is important to increase the hardness.

WTi alloys are presently considered promising candidates for plasma facing components in advanced nuclear energy systems. The mechanically alloyed WTi model alloys consolidated by different techniques were investigated. The effect of different amounts of the dispersed oxide particles on characteristics and properties of the WTi materials was also discussed. The results show that a homogeneous fine grain structure without formation of Ti-rich oxides is obtained in the model alloy sintered by spark plasma sintering. The (W,Ti)C solid solution and α″-Ti martensite phase are also found in the alloy confirmed by TEM investigation, which can be contributed to the effect of the carbon contamination and cooling rate during the process. In this work, it is clear to demonstrate that the presence of different carbides and Ti phases plays an important role in determining hardness and elastic modulus of the materials. The microstructure homogeneity and mechanical properties of the alloys can be further improved by increasing numbers of oxide dispersoids.