Highly wear resistant diamond insert with improved transition structure

Abstract

A cutting element includes a metallic carbide body, a first layer of polycrystalline diamond material, and at least one transition layer between the metallic carbide body and the first layer. The polycrystalline diamond material includes a plurality of interconnected diamond grains, first metal carbide particles, and a first binder material in interstitial regions between the interconnected first diamond grains, wherein the first metal carbide particles form a matrix in which the second diamond grains are dispersed and wherein the first metal carbide particles are present in the outer transition layer in an amount ranging from about 15 to 35 volume percent. The at least one transition layer includes a composite of diamond grains, second metal carbide particles, and a second binder material.

What is claimed: 
     
         1 . A cutting element comprising:
 a metallic carbide body;   a first layer of polycrystalline diamond material, the polycrystalline diamond material comprising a plurality of interconnected diamond grains, first metal carbide particles, and a first binder material in interstitial regions between the interconnected first diamond grains, wherein the first metal carbide particles form a matrix in which the second diamond grains are dispersed and wherein the first metal carbide particles are present in the outer transition layer in an amount ranging from about 15 to 35 volume percent; and   at least one transition layer between the metallic carbide body and the first layer, the at least one transition layer comprising a composite of diamond grains, second metal carbide particles, and a second binder material.   
     
     
         2 . The cutting element of  claim 1 , wherein the first layer is on the outermost end of the insert. 
     
     
         3 . The cutting element of  claim 1 , wherein the second binder material is present in the at least one transition layer in an amount ranging from 5 to 20 volume percent. 
     
     
         4 . The cutting element of  claim 1 , wherein the at least one transition layer comprises two transition layers, a first transition layer adjacent the first layer and a second transition layer adjacent the carbide body. 
     
     
         5 . The cutting element of  claim 4 , wherein the second transition layer has a greater metal carbide content than the first transition layer. 
     
     
         6 . The cutting element of  claim 5 , wherein second carbide particles are present in the second transition layer in an amount ranging from 55-80 volume percent. 
     
     
         7 . The cutting element of  claim 5 , wherein second carbide particles are present in the first transition layer in an amount ranging from 35-60 volume percent. 
     
     
         8 . The cutting element of  claim 1 , wherein the first metal carbide particles and the second metal carbide particles comprise pre-cemented tungsten carbide particles. 
     
     
         9 . A drill bit, comprising:
 a bit body; and   at least one cutting element attached to the bit body, wherein the at least one bit body comprises:
 a metallic carbide body; 
 a first layer of polycrystalline diamond material on the outermost end of the insert, the polycrystalline diamond material comprising a plurality of interconnected diamond grains, first metal carbide particles, and a first binder material in interstitial regions between the interconnected first diamond grains, wherein the first metal carbide particles form a matrix in which the second diamond grains are dispersed and wherein the first metal carbide particles are present in the outer transition layer in an amount ranging from about 15 to 35 volume percent; and 
 at least one transition layer between the metallic carbide body and the first layer, the at least one transition layer comprising a composite of diamond grains, second metal carbide particles, and a second binder material.