Since the publication of SuperalIoys II by Sims, Stoloff, and Hagel in 1987, there have been great advancements in the alloy development, manufacturing, coating, and repair of γ' - strengthened nickel-base superalloys. Wider use of single crystal and directionally solidified superalloys in newer industrial turbines has prompted more effort in welding, repair, and properties assessment.

This bulletin reviews, evaluates, and summarizes the recent development and current knowledge of γ' - strengthened nickel base cast superalloys. Out of the vast amount of available literature, we have judicially selected the most representative for each aspect of this complex family of alloys. The alloys to be discussed include those that are most widely used in today's industry. The representative alloys under this category include IN738, GTD-111, PWA-1480, CMSX-4, and other newer single crystal superalloys. Special emphasis has been given to the metallurgy and properties evaluation of these superalloys.

This bulletin serves as a supplement to SuperalIoys II by providing an update on this fascinating class of engineering alloys. Wrought nickel base superalloys which contain less amount of γ', cobalt base superalloys, ceramic materials, and intermetallics are not included in this bulletin.