Micro-structures and mechanical properties of Nb/Re layered composite produced by CVD

In this work, the relatively light niobium/rhenium (Nb/Re) layered composites were produced by chemical vapor deposition (CVD). The micro- structures including the thickness of diffusion layer, phase compositions and interphase thickness in niobium/rhenium composites were studied by SEM and XRD. The phases were consisted of Nb solid solution, χ and Re solid solution. It was observed that increasing of annealing temperature would result in more thick diffusion layer and χ zone. Prolonging annealing time at the same temperature has no profound effect on the formation of interphase χ. Tensile tests indicated that the strength of the as-deposited followed the rule of mixture. For Nb/20 vol.%Re layered composites in which the thickness of phase χ was 1.4 μm, the tensile strength and elongations were about 516 MPa and 8%.