The book deals with the problem of bearing capacity and the fracture of thermally loaded bodies. The treatise is based on extensive experimental and technological data from materials development processes for high-temperature nuclear reactors and aerospace nuclear-rocket engines. Theoretical principles of crack interaction kinetics in non-uniform stress fields and rearrangement of stresses in thermally loaded finite bodies are treated. Electron-beam, induction and ion beam techniques are applied to measure thermal stress resistance. The main regularities of fracture at various modes of local, combined and cyclic thermal loading in a wide temperature range are considered. A new approach to estimate the crack pattern and the bearing capacity of bodies in inhomogeneous fields of thermal and residual stresses is developed on the basis of fracture mechanics. The method can be used to study the fracture behaviour of a surface at local heating and applied strain. The crucial factors influencing thermal shock fracture of fissured and functionally graded materials are indicated. Changes in the thermal stress resistance of carbides (ZrC, NbC, and SiC), graphite containing materials, Si3N4, Y2O3, Sc2O3 Al2O3 and sapphire single crystals, composites and their structural parameters can be studied with this method. The book provides up-to-date information on the physicalmechanical properties of refractory compounds and practical recommendations on possible technological improvements of their thermal-stress resistance.