Process for casting aluminum alloys

US4766948A · kind A · utility

Assignee

• Thyssen Industrie AG · DE

Inventors

• Friedrich Behr
• Heinrich Ballewski · Neukirchen-Vluyn, DE
• Wolfgang Grossmann · Moers, DE

Key dates

• Filing date: Oct 15, 1987
• Grant date: Aug 30, 1988
• Expiry date: Oct 15, 2007

Classification

• Technology area (CPC B): Performing Operations; Transporting
• CPC primary: B22C3/00
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Improved small dendrite arm spacings and good technical values, regarding the technical properties of aluminum alloys, particularly tensile strength, yield strength and elongation percent, can be reliably obtained by refining the grain of the casting to provide the smallest possible spacings between the secondary dendrite arms, by casting the aluminum alloys in a ceramic mold provided with numerous micro-sized rough spots and pores and to the inner wall of which mold after it is dried and fired has been applied a thin layer of a salt mixture in which the cations are primarily from the alkalis and/or alkaline earths and the anions are primarily from halogens and which applied salt mixture has a liquidus temperature lower than the casting temperature of the alloy.