Micro-channel Fabrication by Additive and Subtractive Methods

Micro-channels are widely used in micro-electronics and micro-fluidics applications. Their performance is mainly depending on its surface quality and dimensional accuracy. Micro-milling is a widely used for micro-channel fabrication of different materials. However, burr formation and tool wear are the major issues related to the quality of the micro-channels. Laser Powder Bed Fusion (L-PBF) is a versatile additive manufacturing process by which micro-channels can be fabricated. However, layer by layer fabrication process and the adhered powder particles decrease the surface quality of the micro-channels. So, there is need of post-processing of these channels. In the present study, micro-channels of different cross sections are fabricated by L-BPF process on aluminum alloy. A similar size of micro-channels is fabricated by micro-milling on aluminum alloy block fabricated by L-BPF. Surface roughness, dimensional accuracy, and cross-sectional area of micro-channels are analyzed using 3D surface profiles and scanning electron microscope. Finally, both fabrication processes (direct metal printing and micro-milling) are compared with reference to the quality of micro-channels.