Aluminum Gears with Bonded-in Steel Hubs.--A new gear made of aluminum, with a bonded-in steel hub, has been developed by the A1-Fin Division, Farmingdale, L. I., of the Fairchild Engine and Airplane Corporation, according to M. V. Little, Acting General Manager of the Division. Lighter, and stronger than molded resin and fiber gears, the A1-Fin bonded gear can stand heavier loads.
Perfected after two years of research and testing, the gears, which are hobbed and shaved, are as quiet in operation as the composition type. Made of aluminum alloy, bonded to steel with a molecular process originally developed by M-Fin, the gears have a tensile strength of about 15,000 psi. With steel hubs there is no danger of the aluminum gear conforming to the shaft. The gear has withstood shear tests of the bond up to 98,000 lb.
Aluminum alloys are used for strength and heat treatment of the casting and develop a Brinell hardness of 85 to 120, depending upon requirements.
The patented A1-Fin process of molecularly bonding aluminum and its alloys to steel and iron is a development which permits the fabrication of bi-metallic assemblies combining selected physical properties of both metals and facilitates the production of units requiring the strength, hardness, resilience, and fatigue resistance of steel with the light weight, high heat conductivity, excellent bearing properties, anticorrosive qualities, and other characteristics of aluminum.