Strength and elastic deformation of natural and synthetic diamond crystals shock compressed along [100]

Plane shock wave experiments were conducted to determine the strength and elastic response of natural and synthetic diamond single crystals shocked along (100) to peak elastic stresses of similar to 90 and similar to 120 GPa. Velocity interferometry was used to measure particle velocity histories and shock velocities in the diamond samples. The maximum elastic wave amplitudes (89 +/- 3 GPa) for both crystal types were comparable. This value corresponds to shear stresses of 30 and 35 GPa (similar to G/15) for the (111) [1 (1) over bar0] and (111) [2 (1) over bar(1) over bar] slip systems, respectively. Surprisingly, the elastic limit (57 +/- 3 GPa) was lower for the higher peak stress. The elastic constant C(111) was experimentally determined to be -7804 +/- 653 GPa. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3448027]