Polycrystalline diamond compacts including at least one transition layer and methods for stress management in polycrystalline diamond compacts

A method for manufacturing a polycrystalline diamond compact, the method comprising:

• disposing at least one mixture layer that includes a plurality of diamond particles and tungsten carbide particles between at least one layer of diamond particles and a cemented carbide substrate in a pressure transmitting medium to form a cell assembly;
• and
• subjecting the cell assembly to a high-temperature/high-pressure (“HPHT”) process of at least 1000° C. and a pressure of at least 7.5 GPa in the pressure transmitting medium to form a polycrystalline diamond compact that includes at least one polycrystalline diamond layer, a cemented carbide substrate, and at least one transition layer disposed between the at least one polycrystalline diamond layer and the cemented carbide substrate;
• ramping a sintering temperature of the HPHT process down to an annealing temperature over at least 70 seconds;
• and
• annealing the polycrystalline diamond compact after the HPHT process at the annealing temperature in a range of about 650° C. to about 875° C. and a pressure of about 2 GPa to about 10 GPa for at least about 80 seconds;
• wherein the at least one transition layer is at least partially formed from the at least one mixture layer;
• wherein the at least one transition layer exhibits a thickness of about 0.60 inches to about 0.12 inches and a coefficient of thermal expansion (“CTE”) that is less than a CTE of the cemented carbide substrate and greater than a CTE of the at least one polycrystalline diamond layer;
• wherein the at least one additive is about 25 volume % to about 50 volume % of the at least one transition layer;
• wherein the at least one polycrystalline diamond layer exhibits a coercivity of about 115 Oersteds (“Oe”) or more and a specific magnetic saturation of about 15 Gauss·cm3/grams (“G·cm3/g”) or less.

A method for manufacturing a polycrystalline diamond compact, the method comprising:

• disposing at least one mixture layer that includes a plurality of diamond particles and at least one additive between a layer of diamond particles and a cemented carbide substrate in a pressure transmitting medium to form a cell assembly;
• subjecting the cell assembly to a high-temperature/high-pressure (“HPHT”) process to form a polycrystalline diamond compact that includes at least one polycrystalline diamond layer, a cemented carbide substrate, and at least one transition layer disposed between the at least one polycrystalline diamond layer and the cemented carbide substrate;
• annealing the polycrystalline diamond compact after the HPHT process at an annealing temperature in a range of about 650° C. to about 875° C. and a pressure of about 2 GPa to about 10 GPa;
• wherein the at least one transition layer is at least partially formed from the at least one mixture layer, and wherein the at least one transition layer exhibits a coefficient of thermal expansion (“CTE”) that is less than a CTE of the cemented carbide substrate and greater than a CTE of the at least one polycrystalline diamond layer;
• wherein the at least one polycrystalline diamond layer exhibits a coercivity of about 115 Oersteds (“Oe”) or more and a specific magnetic saturation of about 15 Gauss·cm3/grams (“G·cm3/g”) or less.