Polycrystalline diamond cutters are ultra-hard tools used for oil and gas drilling. They are produced by sintering diamond particles at High Pressure (5.5+ GPa) and High Temperature (1300+ K). After synthesis, the cutter is returned to room temperature and pressure. The significant mismatches in thermal expansion coefficient and stiffness between the diamond table and the tungsten carbide substrate result in residual stresses. The magnitude and distribution of these residual stresses is believed to impact cutter failure rate in industrial use. We have produced finite element models to estimate these residual stress distributions for different substrate-diamond interface geometries. The proposal is to use neutron diffraction to map strains as a means of confirming the residual stress magnitudes and locations experimentally, and for correlation with impact tests