Nickel-Base Gamma Prime Phase

The gamma-prime phase is an intermetallic precipitate in nickel superalloys that gives the material its high strength and creep resistance at high temperatures. When welding, this is the critical point: if the heat input is too high or the part cools too slowly, the phase does not precipitate properly and the material loses its properties. So you have to keep the heat under control and ensure rapid cooling to maintain the desired microstructure.