Patent ID: 8763731

Claim:
A polycrystalline compact, comprising: a hard polycrystalline material, comprising: a first region adjacent a substrate and comprising: a first plurality of grains of hard material having a first average grain size; a second plurality of grains of hard material having a second average grain size smaller than the first average grain size, the grains of the first plurality of grains of hard material and of the second plurality of grains of hard material being interspersed and inter-bonded; and catalyst material for catalyzing the of inter-granular bonds between the grains of the first plurality of grains of hard material and of the second plurality of grains of hard material, the catalyst material disposed in interstitial spaces between the inter-bonded grains of hard material of the first plurality of grains of hard material and of the second plurality of grains of hard material; and a second region adjacent and directly bonded to the first region along an interface between the first region and the second region, the second region having a smaller volume percentage of hard material than the first region and comprising a third plurality of grains of hard material having a third average grain size, the grains of the third plurality of grains of hard material being interspersed and inter-bonded, wherein interstitial spaces between the inter-bonded grains of the third plurality of grains of hard material are at least substantially free of catalyst material for catalyzing the formation of inter-granular bonds between the grains of the third plurality of grains of hard material.