Consolidation behavior of W–20–40 wt.% Mo nanoalloys synthesized by thermal decomposition method

• A simple single-step soft chemical process has been adopted for the synthesis of W-20-40 wt.% Mo nanoalloys.
• FTIR study reveals that l-cysteine binds to the surface of W-Mo nanoalloys via a thiolate linkage, which renders stability with respect to aggregation and growth.
• The relative density is maximum enhanced to 97.5%, 98.1% and 98.9% in W-19.9 wt.% Mo, W-30.4 wt.% Mo and W-40.2 wt.% Mo alloys sintered at 1600 °C respectively.
• The sintered W-Mo specimens also exhibit significantly enhanced hardness values compared to the corresponding micro and nanocrystalline alloys.

W–Mo nanoalloys of variable compositions with average sizes ~ 40 nm were synthesized using a single step soft chemical approach in presence of l-cysteine. FTIR study reveals that l-cysteine binds to the surface of W–Mo nanoalloys via a thiolate linkage, which renders stability with respect to aggregation and growth. As-synthesized W–Mo alloys are found to be amorphous and bcc crystalline peaks developed on annealing at 600 °C. In addition, the effect of nanoscale particles on densification behavior of W–Mo alloy has also been investigated. The relative density of W–19.9 wt.% Mo, W–30.4 wt.% Mo and W–40.2 wt.% Mo alloy compacts sintered at 1600 °C is maximum achieved corresponding to 97.5, 98.1 and 98.9 % respectively. Further, superior Vickers hardness has been achieved in the sintered specimens compared to those obtained from microcrystalline or mechanically alloyed powders.