Elastic and thermodynamical properties of cubic (3C) silicon carbide under high pressure and high temperature
الموضوعات : Journal of Theoretical and Applied PhysicsDinesh Varshney 1 , S. Shriya 2 , M. Varshney 3 , N. Singh 4 , R. Khenata 5
1 - Materials Science Laboratory, School of Physics, Vigyan Bhavan, Devi Ahilya University
2 - Materials Science Laboratory, School of Physics, Vigyan Bhavan, Devi Ahilya University
3 - Department of Physics, M. B. Khalsa College
4 - Department of Physics, Ranchi College
5 - Laboratoire de Physique Quantique et de Modélisation Mathématique (LPQ3M), Département de Technologie, Université de Mascara
الکلمات المفتاحية: Carbide, High pressure, Elastic properties, mechanical properties, Thermal expansion,
ملخص المقالة :
AbstractPressure-dependent first-order phase transition, mechanical, elastic, and thermodynamical properties of cubic zinc blende to rock-salt structures in 3C silicon carbide (SiC) are presented. An effective interatomic interaction potential for SiC is formulated. The potential for SiC incorporates long-range Coulomb, charge transfer interactions, covalency effect, Hafemeister and Flygare type short-range overlap repulsion extended up to the second-neighbour ions, van der Waals interactions and zero point energy effects. The developed potential including many body non-central forces validates the Cauchy discrepancy successfully to explain the high-pressure structural transition, and associated volume collapse. The 3C SiC ceramics lattice infers mechanical stiffening, thermal softening, and ductile (brittle) nature from the pressure (temperature) dependent elastic constants behaviour. To our knowledge, these are the first quantitative theoretical predictions of the pressure and temperature dependence of mechanical and thermodynamical properties explicitly the mechanical stiffening, thermally softening, and brittle/ductile nature of 3C SiC and still awaits experimental confirmations.
