Rahman M Azizur, Rahman Mustafizur, Mia Mozammel, Asad A B M A, Fardin Ahmed
Department of Mechanical and Production Engineering, Ahsanullah University of Science and Technology, Dhaka 1208, Bangladesh.
Department of Mechanical Engineering, National University of Singapore (NUS), 10, Kent Ridge Crescent, Singapore 119260, Singapore.
Micromachines (Basel). 2019 Nov 29;10(12):831. doi: 10.3390/mi10120831.
This paper presents the micromanufacturing of aluminum (Al) alloy microrods using micro turning as a competing process to other nontraditional micromachining methods. In that regard, the challenges in such manufacturing have been identified and overcome. The strategies of step-by-step cutting have also been delineated. In addition, the influence of step size and step length on the cutting and thrust forces were investigated. The chip morphology for micromachining was examined using scanning electron microscopic imagery. The safe dimension of the microrod was calculated and, subsequently, used to fabricate microrod, conical tip rod, and grooved rod from 3 mm long and 1.5 mm diameter rod using an appropriately coded computer numerical control (CNC) micromachining center. Our results showed that the thrust force was responsible for part deflection, emphasizing the necessity for computing safe dimensions. At shallow step sizes, the thrust force was more dominant, causing plastic deformation associated with rubbing and burnishing. The chips produced were irregular and sliced in nature. Conversely, at high step sizes, the cutting force superseded the thrust force, resulting in chips that were spread more along the width as opposed to the depth. The chips also had a smoother interacting surface. Finally, micro turning was successfully implemented to manufacture milli-scale structures (i.e., 3 mm long) with micro features (150 to 230 μm diameter) on aluminum alloy materials.
本文介绍了采用微车削工艺制造铝合金微棒，这是一种可与其他非传统微加工方法相竞争的工艺。在此方面，已识别并克服了此类制造过程中的挑战。还阐述了分步切削策略。此外，研究了步距和步长对切削力和推力的影响。利用扫描电子显微镜图像检查了微加工的切屑形态。计算了微棒的安全尺寸，随后使用适当编码的计算机数控（CNC）微加工中心，从长3mm、直径1.5mm的棒材制造微棒、锥形头棒和带槽棒。我们的结果表明，推力是导致零件偏转的原因，这突出了计算安全尺寸的必要性。在浅步距下，推力更为显著，会导致与摩擦和研磨相关的塑性变形。产生的切屑不规则且呈片状。相反，在大步距下，切削力超过推力，导致切屑更多地沿宽度而非深度分布。切屑的相互作用表面也更光滑。最后，成功实施了微车削工艺，以在铝合金材料上制造具有微观特征（直径150至230μm）的毫米级结构（即3mm长）。
