“The thermodynamic punishment must fit the structural crime.”
To develop and document complex oxide, carbide and nitride thermochemical and thermophysical properties under extreme conditions for next-generation space exploration materials. This leads to 4 key integrated fundamental research themes: (i) Material Synthesis, (ii) Crystallography, (iii) Calorimetry and (iv) Computation. These themes are related to 2 key research initiatives: (i) Materials Design and (ii) Materials Discovery. These initiatives will work to support the key objective of materials to support hypersonics, nuclear fission/fusion reactors and space exploration.
Materials Design is the focus of developing and perfecting material systems that are temperature resistant, pressure-resistant, plasma resistant and radiation-resistant. This includes the development of new experimental devices and techniques that push the limits of extreme environments. These material systems and experimental devices will be essential for engineering applications on earth and space exploration.
Materials Discovery is the focus of identifying and understanding material systems that exist under high temperature, high pressure, harsh plasma, and harsh radiation. All these extreme environments exist in our universe. Thus, we need to have an understanding of the chemical and physical properties of materials in these extreme environments as they could exist in deep space and they could assist us explore deep space.
New complex oxides, carbides, and nitrides will be synthesized using the steric entrapment method. The anisotropic thermophysical properties, viz., thermal expansion, compressibility and molar volume strains (related to the partial molar volume of mixing) will be measured using in-situ powder diffraction as a function of temperature, pressure, composition, radiation, and plasma respectively. These thermophysical parameters will be documented for engineering applications and will be used to determine crystallographic orientation relations and lattice variant deformations (related to changes in shape and volume) of any observed transformations. This will be complemented with symmetry decomposition analyses to completely describe the symmetry relations between crystal structures. The phase transformation data will be used to assess if these materials can potentially be used as transformation toughening or shape memory ceramics. Thermochemical properties, viz., heat capacity, enthalpy of formation, the entropy of formation and enthalpy of mixing will be measured to determine the stability of the newly synthesized compounds. Density functional theory (DFT) will be utilized to model the observed thermophysical and thermochemical properties from first principles. This information will influence the choice of future compositions for potential applications as high temperature, energy storage or structural materials. Finally, with the aid of the CALPHAD method, the complex oxide, carbide and nitride phase diagrams will be produced and optimized based on the experimentally measured thermophysical and thermochemical data.
This work is a multidisciplinary endeavor, aimed at merging ideas from: (i) materials synthesis, (ii) crystallography (advanced symmetry and experimental analysis), (iii) calorimetry and (iv) computation (CALPHAD) to help tackle the space exploration challenge through the identification and fundamental understanding of new extreme environment (high temperature, high pressure, radiation resistant and plasma resistant), energy storage and structural materials.
Innovation | Diversity | Comradery | Humility | Self-Improvement