A Low Contact Force Polishing System for Micro Molds that Utilizes 2-Dimensional Low Frequency Vibrations (2DLFV) with Piezoelectric Actuators (PZT) and a Mechanical Transformer Mechanism

This study proposes and develops a novel polishing system for micro molds which need high precision polishing, high aspect ratio of micro channel structure, or further miniaturization for micro channel structure. The proposed system has been named a “low contact force polishing system for micro mold utilizing 2-dimensional low frequency vibrations (2DLFV) with piezoelectric actuators (PZTs) and a mechanical transformer mechanism.” The system consists of 2DLFV with PZTs incorporated into the mechanical transformer structure, a low contact force loader, and a polishing tool. The shape of the polishing tool is flexible and can be changed depending on the complicatedness of the shape of the work. Several experiments are conducted to evaluate the performance of the polishing system. The evaluation reveals that a convex removal footprint can be easily achieved with the polishing system. The fact that the relationship between the removal depth and the polishing time suit Preston’s law well shows a stable polishing process is realized with the system. The polishing performances remains the same even if the shape of the polishing tool is changed. This indicates that the system can use polishing tools of a wide selection of shapes, which allows the system to polish a large variety of materials and most of the complicated shapes of metal structures, achieving a dramatic reduction in surface roughness. The plano raster polishing results also show the system to be well suited to the dwell time control polishing because the results show the removal footprint to be proportional to the dwell time and the defined raster path. All in all, the system is a versatile polishing system capable of achieving the intended objectives.