Pesquisas e Relatórios sobre Metais

Silicide-Molybdenum Fibrous Composites: Fracture Toughness and Creep Resistance

Mileiko ST, Chumichev VA, Novokhatskaya NI, Shakhlevich OF, Stolin AM, Bazhin PM and Prokopenko VM

There is shown a possibility to use the internal crystallisation method, which was developed earlier as a base for crystallisation of oxide fibres in a molybdenum matrix, to produce silicide/molybdenum fibrous composites. A series of the experiments resulted in obtaining composites with Mo3Si-based fibres and molybdenum alloy matrix. Composite specimens obtained have microstructures typical for fibrous composites with a strong fibre/matrix interface bonding. Some peculiarities are arisen as a result of the particular fibre/matrix system under consideration. The composites are characterised by high creep resistance at temperatures up to 1400°C and sufficiently high fracture toughness at room temperature. The results obtained show ways of designing new metal matrix composites for very high temperature use.