Ultrasonic Coupling Processing: a Novel Technique for Fabrication of Metal Matrix Surface Composites

A novel surface modifying technique, ultrasonic coupling processing (UCP), was developed to fabricate the TiAl₃ particle-reinforced Al matrix surface composite. The effects of UCP on the microstructures and wear resistance of the Al matrix surface composite were investigated. The results show that the TiAl₃ particles are driven toward the sound pressure node by the acoustic radiation force coupled with a low intensity ultrasonic field. The reinforced particles move toward a definite direction in the stable stationary field under the ultrasonic coupling condition. The hardness of the surface composite takes on a graded distribution due to the distribution of TiAl₃ particles along the longitudinal direction. The interface between the matrix and reinforced phase bonds well, and the wear resistance of the composite increases significantly.