Because of the higher density of concentrated fluxes of solar energy, it is possible to produce surface layers using materials which contain new phases and have special structures and properties. The solar rays do not contaminate the treated surface and can produce any thermal regime of interaction of the solid with the gas and subsequent rapid cooling of the surface layer. The development of processes based on solar radiation makes it possible to affect in the required direction the structure and properties of the surface layer and, at the same time, greatly widen the range of application of materials. The increase of the strength and corrosion resistance at high service temperatures is of special importance for refractory materials.