| The contact forces and surface characteristics of two aluminum alloys in a vibratory finishing process have been investigated. A new surface force sensor was used to measure simultaneously the normal and tangential forces produced by the ceramic media in a tub vibratory finishing machine. These forces were then correlated with the resulting changes in surface roughness, hardness, curvature, and wear rate of the aluminum workpiece. The principal variables were the degree of lubrication, finishing duration, and aluminum alloy. Further observations of media motion obtained using a miniature video camera and SEM micrographs of impact craters helped determine the contact mechanics of the finishing media and the wear mechanisms of AA1100-O and AA6061-T6 alloys.; Experimental results revealed that, in the dry finishing condition, media contact tends to the normal direction, with increased media sliding occurring in the water-sprayed condition. Hardness, roughness, curvature and wear rate changes of the workpiece were strongly dependent on the lubrication condition. |
