Microstructure and High Temperature Mechanical Property of Directionally Solidified NiAl-Cr(Mo)-W/Nb Alloy
The microstructure, high temperature tensile behavior of the DS NiAl-Cr(Mo)-W/Nb alloy have been investigated. The transverse microstructure of the alloy consists typically of eutectic colonies of NiAl and Cr(Mo) phase with white phases segregating at the cell boundaries. The white phase is possibly Cr(Mo) phase containing large amount of Nb and W elements. The longtitudinal microstructure of the alloy is lamellar with the direction basically parallel to the directional solidification direction. The tensile yield strength and ultimate strength of the DS NiAl-Cr(Mo)-W/Nb alloy are much higher than that of the general cast NiAl-Cr(Mo)-W/Nb alloy, and the elongation of the alloy is also higher than that of the general cast alloy. The fracture is debonding along phase boundary and cleavage.
Jianzhong Wang and Jingang Qi
Y. H. Qi et al., "Microstructure and High Temperature Mechanical Property of Directionally Solidified NiAl-Cr(Mo)-W/Nb Alloy", Advanced Materials Research, Vols. 299-300, pp. 167-170, 2011