Materials, Properties and Design

Turbine Blade Alloys

· In order to design a super-alloy it is necessary to understand the thermodynamic stability of the phases present as a function of composition. The binary phase diagram opposite is the basis for this understanding.
· To have stable γ and γ'-phases at 1600 K the alloy composition should be Ni - 21 atomic % Aluminum.
· This alloy will remain a two-phase system over the temperature range between 0 K and the eutectic temperature (~1600 K)

From: Weidman, Lewis, & Reid, "Structural Materials," Butterworths (1990)