Effects of Supplying Oil Mist and Water Mist with Cold Air on Cutting Force and Temperature in End Milling of Difficult-to-Cut Materials

Abstract

This paper discusses the cutting temperature and cutting force in end milling difficult-to-cut materials cooled with several types of mists and low-temperature air. The cutting tool was a throwaway end mill with a carbide tip coated with titanium aluminum nitride. The Ti-6Al-4V titanium alloy and AISI D2 hardened steel were used as workpieces. The tool flank temperature and cutting force were measured simultaneously during side milling. The temperature was measured using a two-color pyrometer with an optical fiber. Oil mist and water mist from a mist generator were supplied to the cutting point along with cold air at approximately -27 °C. Compared with dry cutting, the cooling effects of supplying an oil mist and/or cold air were less than for other supply conditions in titanium alloy cutting. However, when water mist was added, the tool flank temperature clearly decreased. The cutting force increased for cases that included water mist. The adhesion of the titanium alloy to the cutting edge of the worn tool was significantly suppressed by supplying water and oil mist with cold air. Tool flank wear also decreased under those lubrication conditions.