Experimental analyses to investigate the feasibility and effectiveness in using heat-pipe embedded end-mills

This study experimentally verifies the feasibility and effectiveness of heat-pipe cooling in end-milling operations. The basic idea is to embed a heat-pipe at the center of an end-mill with the evaporator close to the tool tip, and the condenser at the tool end. Thus, most of heat generated on the end-mill tip can be quickly removed dependent on convection heat transfer by means of heat-pipe. The end-milling experiments were carried out on a CNC vertical machining center under three different cooling conditions, including dry milling, fluid cooling, and heat-pipe cooling. The work material was AISI 1040 steel, and hard alloy was chosen for the cutting tool material. Flank wear is considered as the criterion for tool failure and the wear was measured using a Hisomet II Toolmaker's microscope. The tests were conducted until the end-mill was rejected when maximum flank wear equal to 0.30 mm was recorded. The results validate that heat-pipe-assisted cooling in end-milling processes can effectively perform thermal management comparable to the fluid cooling used pervasively in the manufacturing industry, increasing the service life of the end-mill.