Comparative Performance Analysis of AlTiN, TiAlN, and TiSiN Coated Ball Nose Mills in Machining Stavax ESR

Abstract

Coated carbide end mills have emerged as the essential cutting tools in CNC milling. The coated tools offer robustness, durability and good surface finishing, combining with a good milling setup in precision manufacturing. AlTiN, TiSiN and TiAlN-coated tools have been commercialised and become vital choices in the industries involving high-hardness metals. In the study, commercial AlTiN, TiSiN, and TiAlN coatings on 6 mm carbide ball-nose end mills were compared in terms of structural integrity in the 3-axis CNC mill machining of shallow curved Stavax ESR. A focused electron beam microscope was used to inspect the surface integrity of the post-milling ball noses. The experiments reveal that TiAlN-coated ball nose excel in durability, with minor coating delamination following AlTiN-coated tool. The TiSiN-coated ball-nose mill exhibited the lowest performance of all three coated tools. The mechanical breakage of the TiSiN coating suggests it is the least suitable option for the precision milling of shallow curved surfaces in this material grade.