Strengthening Mechanisms in Some Single-Crystal Superalloys
The creep behavior and microstructure of several nickel-base single-crystal superalloys after high-temperature low-stress creep have been investigated. These alloys were designed with varying content of the alloying elements Mo and Ru. At 1100°C and 137 MPa, the large g/g¢ lattice misfit in negative with the addition of Mo leads to the formation of dense interfacial dislocation networks. These dislocation networks are effective to strengthen the alloys during creep by preventing the penetration of the g dislocations into the g¢ phase.
Z.Y. Zhong, H. Saka, T.H. Kim, E.A. Holm, Y.F. Han and X.S. Xie
Y. Koizumi and H. Harada, "Strengthening Mechanisms in Some Single-Crystal Superalloys", Materials Science Forum, Vols. 475-479, pp. 623-626, 2005