High temperature oxide-fibre/metal-matrix composites

Three families of metal matrix fibrous composites are considered in the paper as potential candidates for future heat resistant materials. Strength, fracture toughness, creep resistance and oxidation resistance of the composites are described and analyzed. Composites with nickel-based matrix are characterised by quasi-plastic behaviour and acceptable oxidation resistance. However, they cannot be used at temperatures above 1200 °C, which is higher than that for nickel superalloys but lower than the use temperatures for really prospective thermal machines. Discovering possibilities to reduce essentially oxidation rate of molybdenum reinforced with oxide fibres of special chemical compositions makes molybdenum matrix composites being prospective heat resistant materials with high creep resistance at high temperatures and sufficiently high fracture toughness at low temperatures. A large choice of entropy alloys (HEAs) with a variety of the properties as a matrix and availability of large number of oxide fibres produced by internal crystallisation method make oxide-fibre/HEA-matrix composites highly prospective heat resistant materials.