Wear behavior of different coated tools in MQL-assisted milling of magnesium-based rare-earth alloys
Linfeng Li, Jinyang Xu, Guoqiang Guo, Munish Kumar Gupta, Ming Chen
Abstract
One of the most important and often employed indicators for describing machinability and machining quality is tool wear. While flank wear is commonly used to gauge the extent of a worn scar, tool wear is characterized more by its shape than its size. In order to quantify the wear shape, however, more specific data concerning the wear contour is required. With this aim, the present work addressed the fundamental wear mechanisms and failure modes of several coated tools used in the high-speed milling of magnesium-based rare-earth alloys. Uncoated, edge-strengthened, TiAlN-coated, and diamond-coated tools were used under dry and minimal quantity lubrication (MQL) conditions. The cutting energy flow and consumption rules guiding the tool wear processes were then quantified using exergy analysis theory. The results claim that the cutting performances of tools and the surface quality are both enhanced by MQL through reducing adhesion wear. For the unstrengthened tool, a tool wear reduction of 55% could be achieved by MQL. With TiAlN coating, the tool wear could be furtherly suppressed by 49%.