Guyll Bella I, Sanford Brayden L, Pint Cary L, Secor Ethan B
Department of Mechanical Engineering Iowa State University Ames Iowa 50011 USA.
Small Sci. 2025 Mar 18;5(7):2500069. doi: 10.1002/smsc.202500069. eCollection 2025 Jul.
Aerosol jet printing is an additive manufacturing technique with broad materials compatibility, high resolution, and complex geometric capabilities. Despite these advantages, even optimized prints are susceptible to overspray, in which sparse deposition of material outside the primary pattern limits precision and quality for high-value applications. Herein, a method is presented to overcome this by loading the sheath gas with solvent vapor before entering the printhead. This reduces droplet drying in the aerosol phase at the periphery of the aerosol stream, improving line edge morphology, pitch, porosity, and surface finish. This is demonstrated to reduce the overspray extent for a water-based polyimide ink by up to 70 ± 2.3% and decrease the resistivity of a solvent-based silver ink by 34 ± 13%. The ability to regulate droplet evaporation in flight offers versatile control, facilitating a wider range of process parameters and ink chemistries. These experimental results are backed by theoretical analysis and numerical modeling, providing a more refined and generalizable understanding of the underlying process physics. This enables tailored outcomes for a range of challenges including high aspect ratio and high-density patterning with improved surface finish and material functionality for compelling applications in printed and hybrid electronics.
气溶胶喷射印刷是一种增材制造技术，具有广泛的材料兼容性、高分辨率和复杂的几何成型能力。尽管具有这些优点，但即使是优化后的印刷品也容易出现过喷现象，即材料在主图案之外的稀疏沉积会限制高价值应用的精度和质量。在此，本文提出了一种方法来克服这一问题，即在鞘气进入打印头之前用溶剂蒸汽加载。这减少了气溶胶流外围气溶胶相中液滴的干燥，改善了线条边缘形态、间距、孔隙率和表面光洁度。结果表明，这可将水基聚酰亚胺油墨的过喷程度降低多达70±2.3%，并将溶剂基银油墨的电阻率降低34±13%。在飞行中调节液滴蒸发的能力提供了通用控制，有利于扩大工艺参数和油墨化学的范围。这些实验结果得到了理论分析和数值模拟的支持，为基础工艺物理提供了更精确、更具普遍性的理解。这使得能够针对一系列挑战实现定制化结果，包括高纵横比和高密度图案化，同时改善表面光洁度和材料功能，以满足印刷和混合电子领域引人注目的应用需求。
