Key Factors Affecting Durable Anti-Icing of Slippery Surfaces: Pore Size and Porosity.

Slippery liquid-infused porous surfaces (SLIPSs) are widely used as an effective passive approach to reduce icing disasters. However, various porous structures make SLIPSs exhibit different droplet mobility and lubricant stability. Undoubtedly, the substrate surface has a great impact on the durable anti-icing of SLIPSs. Herein, surfaces with different pore sizes and porosities were prepared to study their effects on the performance of SLIPS. The results show that small pores and high porosity are beneficial for the preparation of durable anti-icing SLIPS. The small pore size (about 100 nm) has a strong capillary pressure on the lubricant, and the surface with high porosity (66%) possesses a large lubricant-liquid contact ratio. These two can greatly improve the lubricant stability of SLIPS and achieve rapid self-healing. The SLIPS prepared by a suitable porous surface shows excellent anti-icing performance in the simulated glaze ice and durable anti-icing ability in the long-term icing/deicing cycles. In detail, the prepared SLIPS experiences more than 140 icing/deicing cycles through four effective self-healing while maintaining extremely low ice adhesion (<20 kPa). This work proposes a certain improved SLIPS with small pores and high porosity to achieve excellent durable anti-icing performance, broadening the practical applications of SLIPS.

Influence of Current on Soil Corrosion of Galvanized Steel of Grounding Grids.

Grounding grid materials are vulnerable to soil corrosion, which is detrimental to the safe operation of the grounding grids and even lead to serious accidents of power transmission. In this paper, galvanized steel was used as the typical grounding grid material which was buried in the soil and then electrified with AC and DC current for two weeks. The corroded samples under different current conditions were characterized and compared. The experimental results show that the corrosion degree of galvanized steel gradually aggravated with the increasing of the current, especially under DC current. Further, the mechanism of the influence of current on soil corrosion is explored. It is found that under the same magnitude of current, the corrosion degree of galvanized steel under DC current is greater than that under AC current.