Atmospheric pressure cold plasma jet-assisted micro-milling TC4 titanium alloy

摘要

Micro-milling is a low-cost, efficient, and high-precision machining method for manufacturing tiny parts, and has significant application value in various fields. In order to meet the high-accuracy requirements, several composite micro-milling methods have been proposed. However, these methods cannot change surface characteristics of materials, and poor permeability of cooling medium on the tool-workpiece interface remains unsolved. Atmospheric pressure plasma jet can efficiently improve surface wettability without obviously changing surface microstructures and may have promising application potential in machining of difficult-to-cut materials. Here, we propose to induce atmospheric pressure plasma jet to the micro-milling area to improve machinability and surface quality of TC4 titanium alloy. The influences of plasma jet on material wettability and mechanical property are firstly investigated by conducting plasma modification and tensile experiments. Then, micro-milling experiments of TC4 titanium alloy are performed under different atmospheres (dry, nitrogen jet, plasma jet, minimum quantity lubrication, and plasma jet + minimum quantity lubrication). The experimental results indicate that plasma jet can promote material fracture of TC4 titanium alloy, as well as reduce cutting force and cutting temperature, thereby obtaining better surface quality.