Effects of La₂O₃ addition on the microstructure and properties of activated sintered W-Ni compacts

In order to improve the properties of Ni activated sintered W compacts, La₂O₃ was added to a W-1 wt.% Ni matrix alloy. W-1 wt.% Ni-0.5 wt.% La₂O₃ and W-1 wt.% Ni-1 wt.% La₂O₃ composites were fabricated by mechanical alloying and activated sintering methods. The effects of La₂O₃ content and mechanical alloying duration on the microstructural and physical properties of activated sintered W-Ni compacts were investigated. The results showed that La₂O₃ particles have a significant effect on the density/microhardness values and wear amounts of the samples. The relative density value of 96.39 % and microhardness value of 4.08±0.28 GPa of W-1 wt.% Ni samples increased to respectively 98.09 % and 5.45±0.29 GPa with the addition of 1 wt.% La₂O₃. Wear rate of 3.26±0.81 (mm³N^-1m^-1)x10^-9 of the W-1 wt% Ni samples decreased to 2.10±0.24 (mm³N^-1m^-1)x10^-9 with the addition of 0.5 wt.% La₂O₃. Furthermore, grain sizes decreased and microhardness values increased with increasing mechanical alloying duration.