Nickel superalloy from directional solidification for high creep strength

摘要

A nickel base superalloy for columnar grain, directional solidification which contains Re for strength and creep resistance, and substantially eliminates the use of Zr and minimizes Si to prevent DS grain boundary cracking. The creep- and stress-rupture properties, which approach nickel base superalloy single crystal performance, are achieved without the use of high temperature gamma prime solution treatment. The alloy consists essentially of the following elements (wt.% or ppm) and may also contain from 0 to 0.2% total by weight of one or more of Y, La and Ce: TABLE a