Study on surface modification of aluminum 6061 by multiple ultrasonic impact treatments

摘要

The effects of multiple ultrasonic impact treatments (UITs) on the surface properties of aluminum 6061 (Al 6061) were investigated, based on surface topography, hardness, and erosion. With one UIT pass, the value of the surface roughness decreased from 0.65 to 0.19 mu m, after which it stabilized. Successive UIT passes caused the surface hardness to increase until it became saturated at 128 HV; this occurred after three UIT passes. X-ray diffraction results showed that as the number of UIT passes increased, the diffraction peak intensity decreased significantly and the full width at half maximum value increased. Debris accumulation was observed with successive UIT passes, which indicated that material was removed from the surface or the surface eroded. Multiple UITs did not cause significant damage to the top surface. It is considered that two principal mechanisms were involved in the evolution of the surface morphology over multiple UITs: plastic deformation and surface erosion by continuous strikes.