Chuang Ho-Chiao, Sánchez Jorge, Cheng Hsiang-Yun
Department of Mechanical Engineering, National Taipei University of Technology, Taipei 10608, Taiwan.
Materials (Basel). 2017 Apr 19;10(4):428. doi: 10.3390/ma10040428.
Co-plating of Cu-Ni coatings by supercritical CO₂ (sc-CO₂) and conventional electroplating processes was studied in this work. 1,4-butynediol was chosen as the surfactant and the effects of adjusting the surfactant content were described. Although the sc-CO₂ process displayed lower current efficiency, it effectively removed excess hydrogen that causes defects on the coating surface, refined grain size, reduced surface roughness, and increased electrochemical resistance. Surface roughness of coatings fabricated by the sc-CO₂ process was reduced by an average of 10%, and a maximum of 55%, compared to conventional process at different fabrication parameters. Cu-Ni coatings produced by the sc-CO₂ process displayed increased corrosion potential of ~0.05 V over Cu-Ni coatings produced by the conventional process, and 0.175 V over pure Cu coatings produced by the conventional process. For coatings ~10 µm thick, internal stress developed from the sc-CO₂ process were ~20 MPa lower than conventional process. Finally, the preferred crystal orientation of the fabricated coatings remained in the (111) direction regardless of the process used or surfactant content.
本研究通过超临界CO₂（sc-CO₂）和传统电镀工艺对铜镍涂层进行了共镀。选择1,4-丁炔二醇作为表面活性剂，并描述了调整表面活性剂含量的影响。尽管sc-CO₂工艺的电流效率较低，但它有效地去除了导致涂层表面出现缺陷的过量氢气，细化了晶粒尺寸，降低了表面粗糙度，并提高了耐电化学性。在不同的制备参数下，与传统工艺相比，通过sc-CO₂工艺制备的涂层表面粗糙度平均降低了10%，最大降低了55%。通过sc-CO₂工艺制备的铜镍涂层比通过传统工艺制备的铜镍涂层的腐蚀电位提高了约0.05 V，比通过传统工艺制备的纯铜涂层的腐蚀电位提高了0.175 V。对于厚度约为10 µm的涂层来说，sc-CO₂工艺产生的内应力比传统工艺低约20 MPa。最后，无论采用何种工艺或表面活性剂含量，所制备涂层的择优晶体取向均保持在（111）方向。
