Study on Polishing Characteristics of Pyramidal Structured Polishing Pad
Ryunosuke Sato*, and Yoshio Ichida**
*Graduate School of Engineering, Utsunomiya University
7-1-2 Yoto, Utsunomiya, Tochigi 321-8585, Japan
**CBN & Diamond Nanomachining Institute, Utsunomiya, Japan
We conducted a polishing test to clarify the change in polishing characteristics resulting from the wear of a pyramidal-structured polishing tool, and discuss the polishing mechanism unique to the pyramidal-structured polishing pad. When the pyramidal-structured polishing pad is used for polishing, there exists an initial polishing stage in which the removal rate is high but the finished surface is rough; followed by a steady-state polishing stage in which the wear rate is low, removal rate is stable, and a high-quality finish is obtained. The true polishing pressure is constant in the steady-state polishing stage regardless of the nominal polishing pressure, although it differs with workpiece hardness. Polishing was carried out using the pyramidal-structured polishing pad containing 6 μm alumina abrasive grains for 90 min without any scorching or clogging. This resulted in finished surfaces of 0.4 μm Rz and 0.07 μm Rz for oxygen-free copper and S45C, respectively.
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