Effects of Y2O3 additions on mechanically alloyed and sintered W-4<ce:hsp sp="0.25"/>wt.% SiC composites

In this study, the effect of Y2O3 additions on the microstructural and the physical properties of W-SiC composites was investigated. Powder blends of W-4wt.% SiC, W-4wt.% SiC-1wt.% Y2O3 and W-4wt.% SiC-5wt.% Y2O3 were mechanically alloyed (MA'd) using a Spex mill for 24h. MA'd composite powders were sintered under inert Ar and reducing H2 gas conditions at 1680 degree C for 1h. Microstructural and morphological characterizations of composite powders and sintered samples were carried out via SEM and XRD analyses. Furthermore, density measurements and hardness measurements of sintered samples were carried out. A highest Vickers microhardness value of 11.4GPa was measured for the sintered W-4wt.% SiC-5wt.% Y2O3 while W-4wt.% SiC sample possessed the highest relative density value of 97.7%.