Ultra-High Temperature Materials (UHTMs) are at the base of entire aerospace industry; these high stable materials at temperatures exceeding 1600 °C are used to manage the heat shielding to protect vehicles and probes during the hypersonic flight through reentry trajectory against aerodynamic heating and reducing plasma surface interaction. Those materials are also recognized as Thermal Protection System Materials (TPSMs). The structural materials used during the high-temperature oxidizing environment are mainly limited to SiC, oxide ceramics, and composites. In addition to that, silicon-based ceramic has a maximum-use at 1700 °C approximately; as it is an active oxidation process over low temperature and water vapor environment condition. However, a great emphasis is required for developing structural materials in oxidation and rapid heating environment where the temperature is greater than 1700 °C. This review covers briefly all main types of Thermal Protection Systems (TPSs) and all the materials are used to fabricate them with the maximum operational temperatures. Also, it covers the promised UHTMs (SiC, ZrB2, HfB2, SiB6 and B4C) which are currently using for several aerospace applications, especially for TPS. Besides, it discusses the oxidation of SiC, B4C, SiB6, ZrB2 and HfB2. Therefore, the carbides and borides of the transition metals, Zr and Hf have a high-melting temperature and good stability in forming high-melting temperature oxides.

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The need for wireless sensing technology has rapidly increased recently, specifically the usage of electromagnetic waves which becoming more required as a source of information. Silicon carbide (SiC) Nano particles has been used in this study, the material under test (MUT) was exposed directly to a microwave field to examine the electromagnetic behavior. The permittivity and permeability were investigated with different filler materials to approach best and optimal electromagnetic absorbing characteristics to assist engineers to monitor structure-based composite for defects evaluation that may occur during operation conditions or through manufacturing process. XRD, FESEM and both complex permittivity and permeability were measured for the pure materials that candidate for this study. The results showed that all the selected nanostructure material exhibit a good purity with proper electromagnetic properties in the X- band, this can lead to absorbing and transmission properties that can be used in monitoring structures or manufactured part during fabrication process.

Precision temperature measurement of a nano system with high sensitivity and fast response is still a challenge. The marvelous thermal and mechanical properties of graphite will allow the creation of superior nanoscale temperature sensors. In-situ x-ray diffraction was employed to determine the graphite hexagonal crystal lattice dimensions and the coefficient of thermal expansion based on the calculation of its interatomic distance. The energy of graphite was mapped over the first Brillouin zone in the temperature range of 50 °C–1200 °C at intervals of 50 °C. Energy-based comparative studies between the quantum free electron approach obtained by an inelastic scattering and an harmonic oscillator are introduced by the principal quantum number associated with the excitation level. The hexagonal lattice constants, interlayer distance and interatomic distance of graphite crystals are investigated analytically with consideration given to their temperature dependence and the carbon peak (002), where the 2θ value decreases slightly with increasing temperature. The coefficient of thermal expansion of graphite-based interatomic distance is negative and tends toward zero with increasing temperature, which is in very good agreement with experiments. Moreover, the energy probability distributions enclosed by reciprocal lattice vectors of the hexagonal lattice are defined and interpreted based on lattice dimensions with varying temperature. Linear changes of the temperature-driven unit cell lattice dimensions and analysis of the kinetic energy of the electron in graphite may both be utilised for the advanced temperature interpretation model and preliminary design of a precise nanothermometer.