An Experimental Investigation on Machinability of AZ31B Magnesium Alloy under Dry and Dipped Cryogenic Approaches

Abstract

The use of cryogenic coolants as an alternative cooling technique has been applied widely in recent years because of the many problems associated with conventional cutting fluids. No paper has been published to date on the milling of AZ31 magnesium alloy under dipped cryogenic cooling approach. The comprehensive results from the experimental study have practical importance and provide valuable information for industrial production processes. In this study, milling tests were carried out on AZ31B magnesium alloy under various cutting speeds, feed rates, and depths of cut. During milling, the effects of liquid nitrogen on milling forces, chip formation, and surface roughness were examined and a damage analysis was also carried out. This study introduced a novel cryogenic approach in the milling of AZ31B magnesium alloy using a liquid nitrogen bath. A new experimental setup was prepared for performing milling tests with the approach. Based on the experimental results, it was concluded that using the dipped cryogenic approach improved (approximately 2–34%) the surface quality of the workpiece and provided shorter chip formation. In addition to these, in the tests carried out under dry cutting conditions, lower milling forces (approximately 16–88%) were formed compared to the cryogenic conditions. A surface damage analysis was also performed.