Kwon Yong-Taek, Jeon Sanghyun, Lee Jun, Kim Juheon, Lee Sangmin, Kim Hyungmo
School of Mechanical Engineering, Gyeongsang National University, Jinju 52828, Republic of Korea.
School of Mechanical and Aerospace Engineering, Gyeongsang National University, Jinju 52828, Republic of Korea.
Micromachines (Basel). 2023 Nov 30;14(12):2183. doi: 10.3390/mi14122183.
In this study, we explored the formation of micro-/nanosized porous structures on the surface of a needle composed of STS304 and examined the effect of conventional needles and needles capable of liquid ejection. Aqua regia, composed of HCl and HNO, was electrochemically etched to form appropriately sized micro-/nanoporous structures. We observed that when dispensing liquids with low surface tension, they do not immediately fall downward but instead spread over the exterior surface of the needle before falling. We found that the extent of spreading on the surface is influenced by an etched porous structure. Furthermore, to analyze the effect of surface tension differences, we dispensed liquids with varying surface tensions using etched needles. Through the analysis, it was confirmed that, despite the low surface tension, the ejected droplet volume and speed could be stably maintained on the etched needle. This indicates that the spreading phenomenon of the liquid on the needle surface just before ejection can be controlled by the micro/nanoporous structure. We anticipate that these characteristics of etched needles could be utilized in industries where precision dispensing of low-surface-tension liquids is essential.
在本研究中，我们探索了由STS304制成的针表面微米/纳米级多孔结构的形成，并研究了传统针和能够进行液体喷射的针的效果。由HCl和HNO组成的王水通过电化学蚀刻形成尺寸合适的微米/纳米多孔结构。我们观察到，当分配具有低表面张力的液体时，它们不会立即向下掉落，而是在掉落之前先在针的外表面上铺展。我们发现，液体在表面上铺展的程度受蚀刻多孔结构的影响。此外，为了分析表面张力差异的影响，我们使用蚀刻针分配具有不同表面张力的液体。通过分析证实，尽管表面张力较低，但在蚀刻针上仍可稳定地保持喷射液滴的体积和速度。这表明，在喷射前液体在针表面的铺展现象可通过微/纳米多孔结构来控制。我们预计，蚀刻针的这些特性可应用于对低表面张力液体进行精确分配至关重要的行业。
