Low temperature forging process for Fe-Ni-Co low expansion alloys and product thereof

摘要

A method of treating low-expansion Fe-Ni-Co superalloys is disclosed in which the alloys are forged at a temperature below the recrystallization temperature and then recrystallized without the use of intervening annealing steps. It is necessary that the warm forging step introduce sufficient strain throughout the Fe-Ni-Co superalloy such that after recrystallizing, the superalloy has a substantially uniform microstructure. Alloys produced by this method exhibit good hydrogen charging embrittlement resistance, good strength and/or rupture ductility in moist air.