Laminated Nb/Nb3Al composites: effect of layer thickness on fatigue and fracture behavior

Fracture and fatigue crack growth properties of coarse scale Nb/Nb3Al laminated composites are examined, and their performance is contrasted with similarly reinforced in situ particulate and microlaminate composites. It is found that laminate orientation has a larger effect on fatigue crack growth resistance than on fracture toughness; properties are optimal in the crack arrester as compared with the crack divider orientation. In addition, thicker Nb layers yield improved fracture and fatigue crack growth properties; and the effect is more prominent in the divider orientation. Mechanisms underlying this behavior are briefly described.