The influence of physical vapor deposition (PVD) coating on the microgeometry of high-speed steel (HSS) cutting tools during the machining of wood-based composites

The aim of this work was to analyze the impact of a multilayer TiN/AlTiN nano coating deposited using the physical vapor deposition (PVD) method on the microgeometry and durability of replaceable knives made of high-speed steel (HSS). The blunting process took place while milling standard medium density fireboard with a thickness of 16 mm. Seven reference knives and seven coated ones were used. During durability tests, the wear index value, i.e. the maximum wear on the clearance face VBmax = 0.3 mm was adopted as the blunting criterion. After the blunting stage, the tools were subjected to a precise geometric analysis based on a contact profilometer. In this way, a number of geometric parameters and rounding factors K were obtained for coated and uncoated blades at various points along the cutting edge on a distance 10 mm with 0.5 mm increments. Then, these data were subjected to statistical analysis using the Bonfferoni method. The results showed statistically significant changes in the values of some asymmetry coefficients K at the stage of tool lapping.