Papers by Keyword: One-Sided Pattern Electrodes

Abstract: In this study, we proposed an electro-rheological fluid-aided polisher (ERAP) using one-sided, patterned electrodes. The characteristics of ER fluid and ER fluid containing abrasive grit were investigated. The polishing performances of ER fluids with and without abrasive grit employing ERAP were verified and the following conclusions were obtained. Decreases in viscosity and in the ER effect were observed when highly polymerized liquid crystal (hereafter referred to as HPLC) was diluted with silicon oil. However, the mixing of abrasive grit increases the ER effect, but the ER effect of ER fluid containing abrasive grit decreased when mixed with abrasive grit. The viscosity decreased with increases in aliphatic saturated cyclic hydrocarbon oil (hereafter referred to as NCDM) mixed in highly polymerized compound (one kind of HPLC). The larger the positive dielectric anisotropy, the larger the ER effect in low-polymerized liquid crystal (hereafter referred to as LPLC). The smaller the grit size, the weaker the ER effect. When polished with HPLC, the polished surface was rough due to the large viscosity of an HPLC:silicon oil ratio of 4:14 mixed with #2000WA. However, the smallest surface roughness was attained at 0.5kV/mm for an HPLC:silicon oil ratio of 1:17 mixed with #2000WA. The surface quality was improved at an HPLC: silicon oil ratio of 1:17 mixed with #3000WA. When polished with LPLC, the surface roughness was improved by the increased ER effect when LPLC having a positive dielectric anisotropy was used. However, the surface roughness showed no change when LPLC with a negative dielectric anisotropy was used, due to its small ER effect.

Abstract: In this study, we proposed ER fluid-aided polisher (ERAP) using one-sided, patterned electrodes. The characteristics of ER fluid and ER fluid containing abrasive grit were investigated. The polishing performances of ER fluid containing abrasive grit were verified using an ERAP. The following conclusions were obtained. Thick clusters formed between both electrodes with increased voltage. Abrasive grit was condensed on the thick clusters of ER fluid-particles that formed around the electrodes with further increases in voltage. The ER effect is a hardening of ER fluid under loading by an electric field. The ER effect of ER fluid containing abrasive grit decreased because the grit clusters bound weakly to each other. The ER effect decreased with a decrease of grit size. The surface roughness showed little change when a Shower curtain (a nylon cloth) was used for a pad. An electric field was generated around the cutting zone when a Toraysee (a washable lens cloth) was used as a pad. This leads to large efficiency and high precision in polishing. The surface roughness decreased with increased voltage up to 1.0kV/mm, because the abrasive grit was tightly fixed by the ER effect. A minimum surface roughness was attained at approximately 1.0 kV/mm when using WA and SD grits. The surface roughness increased due to a hardening of the ER fluid, causing deep scratching of the workpiece at 2.0kV/mm.