Published online by Cambridge University Press: 26 February 2011
This paper summarizes recent research on intergranular fracture and alloy design of L12 ordered Ni3X intermetallics. The grain boundaries in Ni3AI, Ni3Ga, Ni3Si, and Ni3Ge are intrinsically brittle, and boron additions are effective in ductilizing the first three alloys but not in Ni3Ge The beneficial role of boron is to increase grain-boundary cohesive strength, to enhance plastic flow in the boundary region, and to disorder grain boundaries. Boron is ineffective in ductilizing Ni3X alloys with × > 25%. The room-temperature ductility of undoped Ni3Al can be improved also by change in grain shape from equiaxed to columnar.
Full text views reflects PDF downloads, PDFs sent to Google Drive, Dropbox and Kindle and HTML full text views.