Bioinspired surfaces with micro/nanostructures have attracted tremendous scientific interests in the aspect of anti‐icing due to their extreme stability and hydrophobicity. Nevertheless, poor durability and stability have greatly hindered their applications. Here, the copper surfaces with four kinds of wood morphologies are obtained via Zr‐based metallic glasses (MGs) as the intermediate template, i.e., thermoplasticity of MGs in the supercooled liquid region (SCLR) matters. These as‐prepared copper surfaces show excellent water repellency and remarkably can delay the freezing process. Compared with a smooth copper surface with a water contact angle (WCA) of 39.5 ± 2.0°, these as‐prepared copper surfaces exhibit WCAs of 120 ± 2.2, 132 ± 1.8, 127 ± 1.7, and 123 ± 1.5°, respectively, and their freezing temperatures decrease significantly, from 0 to −5.6, −9.8, −7.2, and −6.8 °C, respectively. Notably, the hydrophobic copper surfaces maintain good stability without losing hydrophobicity while undergoing heat treatments at 200 or 400 °C for 5 h, showing an extreme stability. In contrast, many hydrophobic surfaces prepared by chemical treatments become weak at such high temperatures. Thus, the MGs‐transferred wooden structures provide a time‐saving and low‐cost approach for the preparation of the stable and hydrophobic copper surfaces with anti‐icing, self‐cleaning, and corrosion resistance.

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Ni is widely used in the field of corrosion protection because of its stability, hardness, and ductility. Inspired by the excellent hydrophobicity of walnut wood, imparted by its porous structure, we synthesized a morph-genetic, porous Ni sheet. A pyrolyzed walnut template was immersed in a Ni2+ solution, allowing Ni to be electroplated on the surface and to enter the skeleton’s pores. After calcination and surface modification, a template-free, low-surface-energy Ni sheet was obtained and accurately investigated by scanning electron microscopy and contact angle goniometry to evaluate its morphology and hydrophobicity. The results show that the Ni sheet inherited the complementary structure of the template, and, in turn, its water-repelling ability. We were able to measure contact angles as large as 150°, demonstrating that the new surface morphology endowed Ni with superhydrophobicity.

The reliability of a dynamic system is not constant under uncertain random environments due to the interaction of internal and external factors. The existing researches have shown that some complex systems may suffer from dependent failure processes which arising from hard failure and soft failure. In this paper, we will study the reliability of a dynamic system where the hard failure is caused by random shocks which are driven by a compound Poisson process, and soft failure occurs when total degradation processes, including uncertain degradation process and abrupt degradation shifts caused by shocks, reach a predetermined critical value. Two types of uncertain random optimization models are proposed to improve system reliability where belief reliability index is defined by chance distribution. Then the uncertain random optimization models are transformed into their equivalent deterministic forms on the basis of 𝛼-path, and the optimal solutions may be obtained with the aid of corresponding nonlinear optimization algorithms. A numerical example about a jet pipe servo valve is put forward to illustrate established models by numerical methods. The results indicate that the optimization models are effective to the reliability of engineering systems. It is our future work to consider an interdependent competing failure model where degradation processes and shocks can accelerate each other.

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