Effect of minor alloying additions on the carbide morphology in a single crystal Ni-base superalloy

Carbon and boron have been added to single crystal Ni-base superalloys to increase the yield and defect tolerance, but the effect of these additions on the solidification is not well understood. Carbon was added to the second-generation single crystal Ni-base superalloy, CMSX-4, to form MC-type carbides. Nitrogen and boron were also added in an attempt to alter the carbide morphology. This investigation examines the effect of these alloying additions on the carbide morphology.