Diamond-bonded bodies and compacts with improved thermal stability and mechanical strength

A thermally stable diamond-bonded compact comprising:

• a diamond-bonded body comprising;
• a thermally stable region extending a depth from diamond-bonded body surface, the thermally stable region having a material microstructure comprising a first matrix phase of intercrystalline bonded diamond, and a second phase interposed within the matrix phase;
• a polycrystalline diamond region extending a depth from the thermally stable region and having a material microstructure comprising a polycrystalline diamond matrix phase and a catalyst material disposed within interstitial regions of the matrix phase;
• and
• a substrate attached to the diamond-bonded body;
• wherein the second phase comprises a reaction product formed between a replacement material and the diamond and that bonds a population of the diamond together, wherein the replacement material was not used to initially sinter the diamond-bonded body at high pressure/high temperature conditions, and wherein the thermally stable region is substantially free of the catalyst material.

A bit for drilling subterranean formations comprising:

• a body;
• a number of blades extending from the body;
• and
• a plurality of cutting elements attached to one or more of the blades;
• wherein the cutting elements comprise a thermally stable diamond-bonded compact comprising:
• a thermally stable region extending a depth from diamond-bonded body surface, the thermally stable region having a material microstructure comprising a first matrix phase of intercrystalline bonded diamond, and a second phase interposed within the matrix phase;
• a polycrystalline diamond region extending a depth from the thermally stable region and having a material microstructure comprising a polycrystalline diamond matrix phase and a catalyst material disposed within interstitial regions of the matrix phase;
• and
• a substrate attached to the diamond-bonded body;
• wherein the second phase comprises a reaction product formed between a replacement material and the diamond and that bonds a population of the diamond together, wherein the replacement material was not used to initially sinter the diamond-bonded body at high pressure/high temperature conditions, and wherein the thermally stable region is substantially free of the catalyst material.