ABSTRACT
Most cast nickel-based alloys are derived from wrought alloys (Table 16.1).
The nickel-based alloys are considerably more difficult to cast than austenitic
stainless steels (SSTs). Nickel-alloy castings should never be purchased
using a wrought-alloy trade name. Foundry selection is critical in obtaining
high-quality, corrosion-resistant castings. To develop the required expertise,
a foundry must pour nickel alloys on a daily basis. Other important factors
are dedicated high-alloy patterns, careful alloy selection, and additional
specifications beyond the normal American Society for Testing andMaterials
(ASTM) requirements. Items covered would include foundry qualification,
heat qualification using a weldability test, raw material restriction, heat
treating, non destructive examination and repair welding.
