文摘
Nanodiamond (ND) is a unique material that exhibits interesting surface properties and is capable of storing strain energy. Molecular dynamics simulations using density functional theory were performed on a variety of ND particles, some of which were constructed to specifically incorporate internal strain. The unstrained spherical ND structures were carved out of bulk crystals and relaxed, while the ND with built-in internal strain were constructed as a dense core (compressive strain) encompassed by a thin shell (tensile strain). Both on-axis and off-axis collisions were simulated at 10 km/s relative velocity. Impact energy was enough to partially melt and shatter the ND particles. Upon impact, the outer shell was ruptured and the release of the strained core energy accelerated expansion compared to previous work on bulk-like ND particles. The internal strain also led to greater fragmentation and an increase in the number of reactive surfaces.