AUTOMATIC TRANSMISSION GEAR MATERIALS AND ASSOCIATED PROBLEMS

This paper is a survey of the gear materials utilized in Automatic Transmissions by the major manufacturers of such transmissions. In conjunction with the material usage survey, consideration is given to the raw material form, heat treatment and final physical properties.

The major problems of gear manufacture and some future developments in process methods are discussed.

The paper brings out the fact that there is no uniformity in materials or methods used by all manufacturers, but each manufacturer has developed his own process, because of the particular design of transmission, the availability of equipment and materials or previous manufacturing processes.