Ab Initio Analysis of The Ultra High Temperature Ceramics Uhtcs Under Pressure

Abstract

ABSTRACT newlineSearch for materials that can resist the extreme environments recently motivate newlineattention in Ultra High Temperature Ceramics (UTHCs). UHTC is a material that melts newlineat a temperature of 3000°C or more. For numerous extreme applications, UHTCs are newlinethe better options: Thermal shielding materials on hypersonic aerospace vehicles or reusable newlineatmospheric re-entry vehicles, particular components for propulsion, furnace newlineclasses of ceramic composites are made of borides, carbides and nitrides for instance newlineZrB2, HfB2, ZrC, HfC, TaC, HfN which are categorized by extraordinary melting newlinetemperatures, high hardness, chemical inertness and comparatively excellent oxidation newlinewithstanding in extreme environments. newlineThermodynamic properties of these materials were investigated providing an insight newlineinto the nature of the response of these materials to high temperature and pressure. newlineQuantum ESPRESSO, based on DFT theory (electron-ion interaction), plane wave and newlinepseudopotentials were used to calculate the ground state energy and Kohn-Sham orbital newlinefor various types of structural optimizations. Three main components of the method are newlinePWSCF (plane wave self-consistent field), CP (Car-Parinello), FPMD (first principle newlinemolecular dynamics). newline