Since at least an alloy consisting of a (Mox Wy)C (y>x) phase having the similar property to that of WC and a (Mox Wy)C (x>y) phase having the similar property to that of MoC has two properties, i.e. toughness of WC and heat and deformation resistance of MoC, this embodiment is advantageous more than when using one kind of (Mo, W)C only.