NiAl intermetallic alloy and article with improved high temperature strength

US5516380A · kind A · utility

Assignee

• General Electric Company · US

Inventors

• Ramgopal Darolia · Sharonville, US
• James R. Dobbs · Tallahassee, US
• Robert Field · Birkenfeld, DE
• Edward H. Goldman · Cincinnati, US
• David F. Lahrman · Mason, US
• William Walston · Mason, US

Key dates

• Filing date: Oct 14, 1994
• Grant date: May 14, 1996
• Expiry date: Oct 14, 2014

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C22C19/03
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A NiAl intermetallic alloy and article is provided with improved high temperature strength, particularly stress rupture strength, through the generation of a multiphase microstructure comprising a beta matrix and at least one precipitate phase. The strength properties and microstructure are the result of alloying with at least two elements selected from Ga, Hf, and optionally Ti, Zr, Ta, Nb, and V, in defined ranges. Preferred are at least two of the elements Ga, Hf, and Ti, and specifically preferred are all three. A specifically preferred form of the invention, in atomic percent, is about 45-59% Ni, about 0.02-0.5% Ga, about 0.2 to less than 1% Hf, about 0.1-10% Ti, with the balance A1 and incidental impurities.