超精密切削加工されたAl合金の仕上げ面性状に及ぼす工具摩耗の影響（第１報）

Abstract

Geometrical quality like surface roughness and accuracy of form has been very important in ultra-precision machining. However, because of improvement of quality of finished surface with progress of ultra-precision machining technology, quality of subsurface material like affected layer also becomes important lately. Workpieces are actually machined with a worn diamond tool in machining shops whereas ultra-precision cutting with a single crystal diamond tool is well known as a machining method owing high quality finished surface to a sharp cutting edge of the tool. The purpose of this study is to find out the relation between the tool wear and the work hardened layer and residual stress of a surface machined with a worn tool in ultra-precision cutting process. Wear of cutting edge with large nose radius was observed by a scanning electromicroscope at intervals of a fixed cutting distance. The surface hardness, depth of hardened layer, and residual stress of the machined surface were also measured at the intervals. As a result of experiments and considerations, it was concluded that depth of hardened layer, Vickers hardness, and residual stress increased with increase in tool flank wear and they could be generalized by undeformed chip thickness and width of flank wear at part of cutting edge generating finished surface.