Aluminum superalloys for use in high temperature applications

US9453272B2 · kind B2 · utility

Assignee

• NanoAL LLC · US

Inventors

• Nhon Q. Vo · Skokie, US
• David N. Seidman · Skokie, US
• David C. Dunand · Evanston, US

Key dates

• Filing date: Mar 12, 2015
• Grant date: Sep 27, 2016
• Expiry date: Mar 12, 2035

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C22C21/02
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Aluminum-zirconium and aluminum-zirconium-lanthanide superalloys are described that can be used in high temperature, high stress and a variety of other applications. The lanthanide is preferably holmium, erbium, thulium or ytterbium, most preferably erbium. Also, methods of making the aforementioned alloys are disclosed. The superalloys, which have commercially-suitable hardness at temperatures above about 220° C., include nanoscale Al3Zr precipitates and optionally nanoscale Al3Er precipitates and nanoscale Al3(Zr,Er) precipitates that create a high-strength alloy capable of withstanding intense heat conditions. These nanoscale precipitates have a L12-structure in α-Al(f.c.c.) matrix, an average diameter of less than about 20 nanometers (“nm”), preferably less than about 10 nm, and more preferably about 4-6 nm and a high number density, which for example, is larger than about 1021 m−3, of the nanoscale precipitates. The formation of the high number density of nanoscale precipitates is thought to be due to the addition of inoculant, such as a Group 3A, 4A, and 5A metal or metalloid. Additionally, methods for increasing the diffusivity of Zr in Al are disclosed.