The functional performance and service life of engineering components strongly depend onthe surface attributes, including surface finish, residual stress, and mechanical strength. Modifying surface attributes by mechanical surface treatment is an effective and economical way of improving the overall performance of engineering components and products. In this study, a novel mechanical surface treatment process, piezo vibration striking treatment (PVST), is proposed and realized by a piezo stack vibration device integrated into a CNC machine. Unlike existing mechanical surface treatments, PVST employs non-resonant mode tool vibration to strike the work surface, leading to better control of the induced surface plastic deformation and hence more efficient surface modification. First, the striking force, tool vibration displacement, and resulting surface deformation were investigated using four designed experiments, i.e., tool-surface approaching, single-spot striking, one-dimensional (1D) scan striking, and 2D scan striking experiments. The results demonstrate the feasibility and excellent controllability of PVST in terms of force and displacement correlation and surface deformation monitoring. Then, intrinsic surface roughness and texture produced by PVST were investigated by conducting PVST on mild steel and pure copper with an initially smooth surface (?? ∼ 0.32 ?m). The dependency of the intrinsic roughness/texture on the process parameters was established. Finally, surface roughness/texture improvement by PVST on electron beam melted Ti6Al4V was investigated. It was found that the combined compression and sliding deformation under the negative engagement distance between the striking tool and work surface is most effective in reducing surface roughness (from 48.6 ?m to 3.7 ?m) and transforming surface texture from a scattered pattern to a uniform pattern. This study shows the promising potential of PVST in the post-processing of additively manufactured metal parts.
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