Applicability of Different Isothermal EOS at Nanomaterials

The present study explains the behaviour of nanomaterials such as AlN, CdSe, Ge, WC, and Ni- and Fe-filled-MWCNTs under high pressure. Among the number of isothermal EOSs available, we prefer only two parameter-based isothermal equations (i.e., Murnaghan equation, usual Tait's equation, Suzuki equation and Shanker equation). The present work shows the theoretical study of thermo-elastic properties especially relative compression ( ), isothermal bulk modulus ( ), and compressibility ( ) of nanomaterials. After comparing all formulations with available experimental data, we conclude that pressure dependence of relative compression ( ) for the nanomaterials, are in good agreement for all the equations at lower pressure range. At higher pressure range, Suzuki and Shanker formulations show some deviation from experimental values. 1. Introduction Nanomaterials are currently in the focus of intense research due to their potential for revolutionary technological applications in diverse areas [1, 2]. Nanomaterials can be metals, ceramics, polymeric materials, or composite materials. Their defining characteristic is the very small feature size in the range of 1–100 nanometers (nm). Nanomaterials are not just simply another step of minimization but an entirely different arena. At the nanomaterial level, some material properties are affected by the laws of atomic physics, rather than behaving as traditional bulk materials. Many of the mechanical properties at nanolevel are modified and different from their bulk counterpart, including the hardness, elastic modulus, fracture, toughness, scratch resistance, and fatigue strength. High hardness has been discovered in many nanomaterials system. Nanosemiconductors with reduced dimensions recently have been shown to exhibit electronic and optical properties which vary with size of the particles, thus making them potential candidates for applications involving tenability of optical and/or electronic properties [3–5]. Tungsten carbide WC is an important nanocomposite, because of its high melting point and hardness; it is important materials in both industry and high-pressure research. WC finds extensive applications in industrial machinery as cutting tools and abrasives. WC is also widely used as anvil materials in multianvil high-pressure instruments and as seats in diamond anvil cells. Moreover, nano-WC with average grain sizes less than 100？nm has been the subject of active research over the past decades, primarily due to the significant roles grain-size reduction played in the enhancements of mechanical properties [6,