A flow-rate-controlled double-nozzles approach for electrochemical additive manufacturing

The electrochemical additive manufacturing technique based on the meniscus-confined approach has been proved to be a powerful tool for fabricating nanoscale and microscale metal components. The stability of the meniscus is the key in this meniscus-confined approach to achieve high resolution and reliable product quality. In the present study, a double-nozzles design, which consists of a feed nozzle and a suction nozzle, is proposed for the meniscus confined electrochemical additive manufacturing technique. It was demonstrated that the proposed design possessed robust control of the stability of the meniscus by manipulating the feed and suction rates of the two nozzles in a quite large range. Various sizes of menisci can be easily obtained by utilising nozzles with different sizes. Compared with the pressure-controlled single-nozzle approach, the results showed that dense structures without dendrites can be fabricated by the double-nozzles design with larger current density due to the feed-and-suction process at the tip of the nozzles. The proposed flow-rate-controlled double-nozzles design was finally employed to fabricate some copper circuits and a Cu/CuNi thin film thermocouple to demonstrate its potential in fabricating electronic devices.基于弯液面约束法（meniscus-confined approach）的电化学增材制造技术（electrochemical additive manufacturing technique）已被证明是制备纳观与微观金属构件的强有力工具。弯液面（meniscus）的稳定性是该弯液面约束方法实现高分辨率与可靠产品质量的关键所在。本研究针对该弯液面约束电化学增材制造技术，提出了一种由进料喷嘴与抽吸喷嘴组成的双喷嘴设计。研究表明，通过在较大范围内调节两个喷嘴的进料速率与抽吸速率，所提出的设计可对弯液面的稳定性实现稳健调控；通过更换不同尺寸的喷嘴，即可便捷获取多种尺寸的弯液面。与压力控制式单喷嘴方法相比，本研究结果显示，借助喷嘴尖端的进料-抽吸过程，双喷嘴设计可在更大电流密度下制备出无枝晶的致密结构。最终，本研究采用所提出的流量控制双喷嘴设计制备了若干铜电路以及Cu/CuNi薄膜热电偶，以验证其在电子器件制备领域的应用潜力。