John F Mckay

US Patent:

40070654, Feb 8, 1977

Filed:

Feb 28, 1975

Appl. No.:

5/554350

Inventors:

Ralph M. Handren - Crystal Lake IL
John P. McKay - Walworth WI

Assignee:

Arnold Engineering Company - Marengo IL

International Classification:

H01F 104

US Classification:

148 3157

Abstract:

The invention relates to a novel alloy consisting essentially of 13-18% nickel, 7-11% aluminum, 0. 5 to 10% cobalt, 0. 1 to 2% silicon and the remainder substantially all iron, as is produced by heating the alloy composition to a temperature of about 1650. degree. C or above to form a melt and then casting the melt in a suitable mold. After solidification, the casting is heated to approximately 1150. degree. C, held at that temperature for a sufficient time to insure that the whole mass is heated uniformly, and then cooled at the rate of about 300. degree. C per minute. Parts are then given an aging for the purpose of producing uniform magnetic properties throughout the casting. Magnets thus cast, heat-treated and aged as aforesaid produce very stable magnetic properties with typical values of Br = 10,000, Hc = 150 and BH max =. 85. A further improvement in properties can be achieved by a second stage heat treatment wherein castings are heated to about 900. degree. C, held at this temperature for a sufficient time to assure that the whole mass is heated uniformly, and then cooled to about 600. degree.

US Patent:

40212734, May 3, 1977

Filed:

Oct 1, 1975

Appl. No.:

5/619144

Inventors:

Ralph M. Handren - Crystal Lake IL
John P. McKay - Walworth WI

Assignee:

Arnold Engineering Company - Marengo IL

International Classification:

H01F 100

US Classification:

148121

Abstract:

The invention relates to a novel alloy consisting essentially of 13-18% nickel, 7-11% aluminum, 0. 5 to 10% cobalt, 0. 1 to 2% silicon and the remainder substantially all iron, as is produced by heating the alloy composition to a temperature of about 1650. degree. C. or above to form a melt and then casting the melt in a suitable mold. After solidification, the casting is heated to approximately 1150. degree. C. , held at that temperature for a sufficient time to insure that the whole mass is heated uniformly, and then cooled at the rate of about 300. degree. C. per minute. Parts are then given an aging for the purpose of producing uniform magnetic properties throughout the casting. Magnets thus cast, heat-treated and aged as aforesaid produce very stable magnetic properties with typical values of Br = 10,000, Hc = 150 and BH max =. 85. A further improvement in properties can be achieved by a second stage heat treatment wherein castings are heated to about 900. degree. C.