Comparative Study of Surface Roughness in Upskin and Downskin Regions of Conformal Cooling Channel Sections Fabricated with AlSi10Mg, Ti64, 316L in AM-LPBF

Abstract

Conformal cooling channel (CCC), used in many industries such as aviation, molding, biomedical, and robotics, refers to functional fluid channels that provide mass or energy transfer. CCC, which can be produced in limited forms where liquid flow cannot be fully achieved in traditional production technologies, is among the areas where additive manufacturing (AM) offers design freedom. However, in design-integrated CCC productions, sagging and deformation in the pipe section caused by the AM production process and design parameters can cause a decrease in the performance expected from the CCC and cause unpredictable flow problems. The producible CCC section from research constitutes the scope of this study. In this study, the production of cylindrical test specimens with eleven channel cross-sections between 0,4 mm and 9 mm using laser powder bed fusion (LPBF) technology using AlSi10Mg, 316L, and Ti64 materials and the roughness measurements of the upskin and downskin regions and the scanning electron microscope (SEM) examination are comparatively discussed. Inconsistent results were obtained in the surface roughness measurements of the 0,4 mm and 0,5 mm diameter holes considered within the scope of the research due to the diameter being below the production limits. This research shows that surface roughness in the upskin parameter region is more acceptable in all material types. In the laboratory measurements obtained, it is seen that the downskin region surface roughness value in the holes produced with AlSi10Mg is higher than other materials, and it is lower in the holes produced with Ti64 than other materials.

Keywords

• Additive manufacturing
• laser powder bed fusion
• AlSi10Mg
• 316L
• Ti64
• conformal cooling channels

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