Deformation behavior of diamond-like phases: Molecular dynamics simulation

The variations of the structure and properties of the diamond-like materials is now of high interest because diamond-like carbon phases has a wide range of commercial applications, especially as the protective coatings with its unusual mechanical properties and strength close to the strength of the diamond. Here the deformation behavior of the stable diamond-like phases is carefully analyzed by molecular dynamics simulation. Five stable structures (A3, A7, A8, A9 and B) based on the fullerene-like molecules are considered. The structural transformations during hydrostatic tension and compression are investigated to understand the deformation mechanisms. Deformation at hydrostatic tension can be divided into three regimes depending on the deformation mechanism. It is found that diamond-like structures can be hydrostatically compressed until the diamond densities, but most of them are losing crystalline order and transform to the amorphous state. Thermal fluctuations decrease the critical strain values at hydrostatic tension but have almost no effect on critical compression strain.