The main strengthening mechanism for Ni-based superalloys results from the precipitation of the ordered L12 γʹ phase and the production of the duplex γ+γʹ structure, which is different from that traditionally employed in Co-based alloys, which depends on the precipitation of carbides. The Co-Ti system exhibits the L12 γʹ phase as does the Al-Ni binary system as employed in Ni-based superalloys. In addition, ternary phases with the L12 structure have been seen in the Al-Co-W system (although metastable), thus making the prospect of developing high-strength Co-base alloys as possible replacements for Ni-based superalloys in high-temperature aerospace applications worthy of further investigation [2006Sat, 2018Rua...
Cited references - 24, figures - 11, tables - 3, chapters - 8