Investigation of dry cutting and mist cutting in ball end milling based on response surface analysis

In order to reduce the use of cutting fluid and the environmental hazard, this paper presents the investigation of the machinability of ball-end milling process with the dry cutting and the mist cutting for carbon steel on 5-axis CNC machining center. The relations of the surface roughness, the flank wear, and the cutting parameters, which are the spindle speed, the feed rate, and the depth of cut, are examined and analyzed based on the experimental results by using the Response Surface Analysis with the Box-Behnken design and the analysis of variance. The in-process cutting force is also monitored to analyze the relations of the surface roughness, the flank wear, and the cutting parameters. The dynamometer is installed on the table of 5-axis CNC machining center to measure the in-process cutting forces. The proper cutting condition for the dry cutting and the mist cutting can be determined easily referring to the minimum surface roughness of the surface plot, which is calculated by the surface roughness model obtained from the Response Surface Analysis. The effectiveness of the obtained surface roughness model has been proved by utilizing the analysis of variance at 95% confident level.