Structure and Mechanical Properties of the Layered Composites Made of Multicomponent Niobium Alloys and Hardening Silicon–Carbon Compounds Formed by Solid-Phase Sintering

—The microstructure and the mechanical properties of the layered composite materials fabricated by diffusion welding of stacks of niobium foils with a one-sided silicon-containing multicomponent metallic coating are studied. The multilayer structure of the composites consists of a viscoplastic niobium alloy and niobium compounds with silicon and carbon. The bending tensile strength of the composites is 200–320 and 260–420 MPa at 1100 and 1300°C, respectively, and is 320–550 MPa at room temperature.