Surface Reforming Method of Aluminum Alloy Members

Author:  Kazuhiko Shiral; Massaru Takatoo, Hiroshima, Japan
Source:  US Patent 5,302,218
Doc ID:  1994042
Year of Publication:  1994
Abstract:  
An aluminum alloy member is heated to 470-550 C., and is quenched to room temperature for hardening. Then the aluminum alloy member is heated to 160-220 C., and is cooled, which is carried out in a cooling process of a tempering treatment. As the aluminum alloy member is in a softening state in the cooling process, plastic working such as shot peening treatment is performed on the surface of the aluminum ally member. Thereafter, the temperature of the aluminum ally member falls to room temperature. In this way, it is possible to generate a great amount of compression residual stress in the aluminum alloy member, without performing a severe plastic working treatment on the surface thereof. Since the present invention requires no severe plastic working treatments on the surface of the aluminum alloy member, this causes no severe surface roughness thereon.