Papers by Author: Rikio Hikiji

Abstract: The reaming deals with cutting and burnishing simultaneously and needs a severe cutting performance. The cutting mechanism is so complicated that the method of evaluating the effect of the cutting fluids on the finished surface integrity is not easy. In this study, the examination was carried out to extract an optimum cutting fluid in Incoloy 825reaming. That is, instead of reaming, the simple method was established to experimentally investigate the effect of the cutting fluids on the finished surface integrity, such as the maximum height and dimensional errors. This method is applicable to reaming processes supported by devising the tool geometry and the cutting conditions in facing with the lathe. As a result, it was clarified that the synthetic soluble showed good performance for the finished surface integrity and this simple method was effective for the evaluation of the optimum cutting fluids in Incoloy 825 reaming.

Abstract: With the improvement of accuracy in machine tools, ultra precision final machining has been carried out by cutting instead of grinding. In addition, JIS method for cutting fluids is revised in order to consider earth environment. However, it is very difficult for workshop to extract an optimum machining condition. The results of this study contribute to extraction of an eco-friendly machining method and reduction of running cost as well as the excellent surface integrity. This time, final machining for high chromium cast iron as the turbocharger parts of the automobile was taken up as an example which acquired the good finished surface by cutting. Namely, for the purpose of reducing the running cost, instead of honing that has been used for finishing it in the hole processing, reaming was carried out for finishing, and its practicability was investigated experimentally. As a result, it was clarified that the surface integrity was improved with the oil hole reamer and the synthetic soluble oil.

Abstract: In the ultra-precision machining, the smaller the undeformed chip thickness is, the more the machined surface integrity is affected by the cutting edge roundness of the cutting tool. In this research, the work hardened surface layer was dealt with as an evaluation of the machined surface integrity and the effect of the mechanical factors on work hardening was investigated experimentally in orthogonal cutting. In the case of a rounded cutting edge, unlike a sharp one, it makes the generation mechanism of the work hardened surface layer complicated. In this research, the mechanical dominant factors were investigated by comparing the effect of the rounded cutting edge on the work hardened surface layer, which counts for much in ultra precision machining involved in small undeformed chip thickness, with that of the sharp cutting edge.