This primer describes the conditions for which a nickel based superalloy might be chosen. It also lists the different elements which are often present and describes the major phases present: gamma (the matrix phase), gamma' (the strengthening precipitate), carbides, borides and the deleterious, topologically close-packed phases.

SOURCE: Reed, Roger. "Physical Metallurgy and Microstructure of Superalloys." University of Birmingham (February 2007.)