HOLD AND COOL PROCESS FOR SUPERALLOY JOINING

摘要

Ni base superalloys containing relatively large amounts of Al and/or Ti are known to be difficult to weld satisfactorily. As the Al and Ti content of the superalloy is increased to improve the strength, the weldability of the component is drastically reduced. It is concluded herein that reducing the γ′ phase improves weldability. A stepwise, controlled heating and cooling process is described to be used in cooperation with a welding process to reduce the γ′ present and thereby improve weldability.