Nickel based monocrystalline superalloy, method of heat treating said alloy, and parts made therefrom

US5047091A · kind A · utility

Assignee

• OFFICE NATIONAL D'ETUDES ET DE RECHERCHES AÉROSPATIALES · FR

Inventors

• Tasadduq Khan · Vélizy-Villacoublay, FR
• Pierre Caron · Les Ulis, FR

Key dates

• Filing date: Aug 10, 1989
• Grant date: Sep 10, 1991
• Expiry date: Aug 10, 2009

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C30B33/00
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

A monocrystalline superalloy with a nickel based matrix and particularly intended for the manufacture of turbine blades, has the following composition, by weight: Al=5.4% to 6.2%; Co=4% to 7%; Cr=6% to 9%; Mo=0% to 2.5%; Ta=5.5% to 8%; Ti=O% to 1%; W=7% to 9%; and Ni=balance to 100%. The invention also provides a method of improving the alloy's resistance to creep, in which the Ni.sub.3 Al type .gamma.' phase is put completely into solution at a first temperature, and then the .gamma.' phase is precipitated into the .gamma. solid solution at a temperature greater than 1000.degree. C. This treatment considerably increases the alloy's resistance to creep over a wide range of temperatures.