WC/Co Tool Wear in Dry Turning of Commercially Pure Aluminium

Abstract

Dry turning of commercially pure aluminum was performed with carbide inserts to generate tool wear. Thus, the wear on the carbides tools were generated by purely interacting with aluminum and without any abrasive, which would be the baseline wear for all aluminum alloys. The flank wear was the main mode, which increased with the cutting speed and decreased as the grain size of the carbides increases. Two types of tool wear pattern have been observed with scanning electron microscopy (SEM) and laser scanning confocal microscope (LSCM): (1) the cavities left from the carbide grains which were dislodged by the adhered layer of the work material and (2) the abrasion on the flank surface caused by the dislodged carbide grains. The width of the scoring marks was correlated with the carbide grain size, which corroborates the abrasion by the dislodged carbide grains from the carbide tool. Energy-dispersive X-ray spectroscopy (EDX) showed that the concentration of the cobalt binder was reduced on the worn area of the insert. The preferential wear of the cobalt binder is believed to facilitate the carbide grain pull-out. Therefore, the wear mechanism in turning pure aluminum is a combination of adhesion and abrasion.