Influence of Ru on the hardness and fracture toughness of WC-VC-Co alloys

The effects of Ru additions on the hardness and fracture toughness of WC-VC-Co alloys were investigated on the following compositions: 80WC-10VC-(10-x)Co-xRu (0 ≤ x ≤ 3) (wt%), (89.6-x)WC-10Co-0.4VC-xRu (0 ≤ x ≤ 2) (wt%), (89.2-x)WC-10Co-0.8VC-xRu (0 ≤ x ≤ 2) (wt%) and 89.6WC-(10-x)Co-0.4VC-xRu (0 ≤ x ≤ 3) (wt%). Hardness increased with increased Ru additions in all alloy series due to a combination of decreased grain size and increased solid solution strengthening. Ruthenium additions generally compromised fracture toughness, although there was improvement for some compositions.