Study on cutting of hardened steel by PCD end mill tool

The hardened die steel was machined by the PCD end mill tool under various cutting conditions. The present study using the PCD tool is focused the main purpose on the reduction of the hand-finishing processing time and. the thickness of the affected layer by making use of diamond characteristics. Three kinds of the mist cooling methods were applied to reduce the tool wear and the cutting temperature. The well cooling effect of the mist cooling is expected to produce the wide application of the PCD tool even to the fine finishing of the hardened ferrous materials. The width of flank wear and the surface roughness of work material with an increase in the cutting length were measured. The flank face of tool was also observed by an EDX/SEM and the laser scanning microscope. From the experiment results, although there were few effects of the mist cooling on the reduction of the cutting temperature, the tool wear was clearly reduced by an oil-water mist cooling method among three kinds of the mist cooling methods. A new mechanism was discussed through the detailed observation of the flank face using an EDX.