Development of the crack propagation resistant intelligent materials (1) mechanism of Nb-Al intelligent material

摘要

A concept of the crack propagation resistant intelligent materials to avoid brittle fracture in case of a shock loading and to provide with excellent mechanical property is investigated. Potential needs for nuclear power plants, aircraft and space structure are expected to provide with reliability and safety. One of the candidates is a Nb and Al fiber reinforced composite. In case of a hypervelocity impact, dynamic energy will provide with Nb{sub}3Al which features high temperature resistance. It may be effective to reduce damage as minimum as possible. Such candidate material has been manufactured by the mechanical alloying (MA) process to avoid formation of intermetallide during sintering, and was subjected to laser beam and arc attack to simulate hypervelocity impact. An EPMA analysis revealed possibility of Nb{sub}3Al and NbAl{sub}3 formation in the vicinity of a heat affected zone of the attack. Therefore Nb and Al interdiffusion in the order of 20 μs has been confirmed.