Post‑Process Drilling of AlSi10Mg Parts by Laser Powder Bed Fusion

Abstract

In the last decade, additive manufacturing (AM) technologies have had an extraordinary research interest in each of the relevant topics: essential manufacturing method development, raw materials, optimization of process parameters, characterization of the fnal product, residual stresses, material microstructure, and modeling. After these developments, additive manufacturing processes started to be rapidly included in industrial production. The needs and problems encountered in practice bring new research topics. An industrial product generally combines many parts produced by diferent manufacturing methods — machining results in higher geometric accuracy and surface fnish than the additive manufacturing process. Therefore, additively manufactured parts will require post-process drilling of products to achieve necessary tolerances. This study discusses the drilling performance of additively produced AlSi10Mg parts with diferent drill bits post-process. This study investigates thrust force, surface roughness, temperature, and chip formation in drilling AM AlSi10Mg parts with HSS-G, TiN, and TiAlN drills. The thrust force values obtained in the building direction are higher than in the transverse direction, albeit by a small margin. A signifcant diference of 23% in drilling tool torque values and up to 35% in thrust force values was measured. The lowest thrust force and torque were obtained with the TiN-coated drill bit, while the highest was with the TiAlN. TiAlN cutting tool exhibits the highest temperature value of 80.6 °C. The laser traces form a layered structure in the Z direction, and the cutting edge coincides with more grain boundaries, making it difcult to drill in this direction.