Postgrowth regime optimization of temperature and pressure reduction in HPHT diamond crystal growth method

Along with exceptional strength characteristics, typical of the diamond is significant brittleness. In particular, an appreciable fraction of diamonds grown using HPHT technology, crack when the rigid P-T conditions inherent to the crystal growth process are gradually reduced. The cause of cracking is excessive stresses associated with the deficiency of plastic properties of the diamond growth medium at certain stages of P-T reduction. A significant contribution to the crystal cracking probability can also be made by the insulating container which encorporates the growth medium and a part of the heating circuit. The paper considers the possibilities of minimizing the mechanical stress in the growth cell and, consequently, in the diamond by choosing the optimal trajectory of the pressure and temperature reduction.