Purpose

Additively manufactured objects have layered structures, which means post processing is often required to achieve a desired surface finish. Furthermore, the additive nature of the process makes it less accurate than subtractive processes. Hence, additive manufacturing techniques could tremendously benefit from finishing processes to improve their geometric tolerance and surface finish.

Design/methodology/approach

Rotary ultrasonic machining (RUM) was chosen as a finishing operation for drilling additively manufactured carbon fiber reinforced polymer (CFRP) composites. Two distinct additive manufacturing methods of fused deposition modeling (FDM) and laser-assisted laminated object manufacturing (LA-LOM) were used to fabricate CFRP plates with continuous carbon fiber reinforcement. The influence of the feedrate, tool rotation speed and ultrasonic power of the RUM process parameters on the aforementioned quality characteristics revealed the feasibility of RUM process as a finishing operation for additive manufactured CFRP.

Findings

The quality of drilled holes in the CFRP plates fabricated via LA-LOM was supremely superior to the FDM counterparts with less pullout delamination, smoother surface and less burr formation. The strong interfacial bonding in LA-LOM proven to be superior to FDM was able to endure higher cutting force of the RUM process. The cutting force and cutting temperature overwhelmed the FDM parts and induced higher surface damage.

Originality/value

Overall, the present study demonstrates the feasibility of a hybrid additive and subtractive manufacturing method that could potentially reduce cost and waste of the CFRP production for industrial applications.

中文翻译：

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增材制造碳纤维复合材料的超声钻孔精加工工艺

目的

增材制造的物体具有分层结构，这意味着通常需要进行后处理以达到所需的表面光洁度。此外，该过程的加法性质使其不如减法过程准确。因此，增材制造技术可以极大地受益于精加工工艺，以改善其几何公差和表面光洁度。

设计/方法/方法

选择旋转超声加工 (RUM) 作为对增材制造的碳纤维增强聚合物 (CFRP) 复合材料进行钻孔的精加工操作。熔融沉积建模 (FDM) 和激光辅助层压物体制造 (LA-LOM) 两种不同的增材制造方法用于制造具有连续碳纤维增强材料的 CFRP 板。RUM 工艺参数的进给率、刀具转速和超声波功率对上述质量特性的影响揭示了 RUM 工艺作为增材制造 CFRP 精加工操作的可行性。

发现

通过 LA-LOM 制造的 CFRP 板中钻孔的质量非常优于 FDM 对应物，具有更少的拉拔分层、更光滑的表面和更少的毛刺形成。LA-LOM 中的强界面结合被证明优于 FDM，能够承受 RUM 工艺的更高切削力。切削力和切削温度压倒了 FDM 零件并导致更高的表面损伤。

原创性/价值

总体而言，本研究证明了混合增材和减材制造方法的可行性，该方法可能会降低工业应用 CFRP 生产的成本和浪费。