Functional gradient materials (FGM) can be obtained by mechanically joining materials with very different physicochemical properties, for example, by soldering glass and metal. As a rule, a change in the properties of an FGM is associated with a corresponding variation of the chemical composition or physical structure of the material. These materials can be produced by by-layer coating with materials of variable composition or by sintering (fusing, welding) of several plates or tablets of different composition. A gradient of material properties can be created by changing the degree of crosslinking (for polymers) or the degree of filling, and along the surface – for example, by changing the degree of modification. A smooth change of these characteristics leads to a smooth variation of the properties, and irregular changes correspond to an irregular form of dependence of the properties on the composition or structure. These materials are mainly used in the production of materials and devices operating in extreme conditions (large gradients of mechanical stress and temperature).