Orthogonal Turning of Aluminum 6061 in Liquid Nitrogen Cutting Environment

Liquid nitrogen is studied as an alternative metal working fluid during the machining of Aluminum 6061-T6 alloy using two different tool materials (HSS and an uncoated carbide). The design of the experiment utilized two feeds (0.002”/rev and 0.004”/rev) with a constant depth of cut (0.125 inch) and 3 different tool rake angles of 0°, 7° and 15°. Force data was collected using Kistler dynometer. Three-dimensional (3D) measurements of the tool wear were analyzed using a 3D Keyence optical microscope in conjunction with a Dektak surface profilometer. When contrasted with dry cutting (hard turning), it was found that the liquid nitrogen increased the tool wear with HSS tools but decreased tool wear using uncoated carbide tools. Effect on cutting forces in all cases was statistically insignificant.