STRENGTHENING MECHANISMS IN NICKEL-BASE HIGH-TEMPERATURE ALLOYS

A review is given of the various mechanisms from which nickel-base superalloys derive their high-temperature strength. The strengthening mechanisms discussed include solid-solution hardening, precipitation hardening, and strengthening with additions of boron and zirconium, which are discussed in terms of dislocation theory. Considerations are given for failures, heat treatment, and related grain-boundary behavior. (B.O.G.)