MATERIALS
INVESTIGATION OF HEAT RESISTANCE AND STRUCTURE OF LAYERED REFRACTORY COMPOSITES REINFORCED BY CHEMICAL COMPOUNDS WITH SILICON, CARBON, AND BORON
In contrast to the melting technologies for the production of high-temperature alloys in the solid-phase technology developed by us, a multi-layer structure of the future composite material is already set at the initial stage of the billet formation. In the work presented, the billets were assembled from Nb- and Mo-foils with one or two-sided coatings of carbon or Si-B. Layered structures of composites were formed during the diffusion welding of packets at 1500°C and a pressure of ~14 MPa. In the place of the coatings, layers of hightemperature carbides or intermetallic Si and B compounds with Nb and Mo formed, which occupied up to ~40% of the cross-sectional area of the composites. The strength and crack resistance at room temperature, strength at a temperature of up to 1500 °C, as well as the modulus of elasticity and density were measured. The presence of intermetallides in the structure of composites leads to a decrease in their density and an increase in the modulus of elasticity.