Zeyu Ma

Porous polydimethylsiloxane (PDMS) elastomers produced using conventional phase separation methods often suffer from limited tribological and mechanical properties. In this study, we present a general approach for the fabrication of porous elastomers with borate-driven heterogeneous networks, which leverage the borate at the two-phase boundary to stabilize the phases, without the need for additives such as surfactants. Pure porous elastomers are created by removing the alcoholysis phases, with precisely controllable pore structure and mechanical performance. Interestingly, under saltwater lubrication, an atypical corrosion–lubrication phenomenon occurs on the porous elastomers, reducing the friction coefficient and wear rate by over 95 and 90%, respectively. Additionally, unique mechanical advantages, such as 1250% of stretch, were predictively imparted to the elastomers by various boric acid functional groups. Our method is generally applicable to various PDMS systems and offers a novel approach for designing pure porous materials for water-lubricated components and flexible sensors.

Investigating droplet wetting and icing behavior is crucial for comprehending the principles of surface icing and the design of anti-icing surfaces. In this study, we present the evidence from molecular dynamics (MD) simulations that reveal a hitherto unreported behavior of droplet wetting and icing adhesion on surfaces with lattice constants from 2.7 to 4.5 Å. Here, we observe that the contact angles (CA) of droplets on a face-centered cubic (FCC) lattice surface consistently correlate positively with the lattice constant. Further examination of droplet behavior on an idealized crystal surface reveals that hydrophilic surfaces (e.g., CA = 85°) inhibit freezing more effectively than hydrophobic surfaces (e.g., CA = 97°). This finding contradicts the conventional explanation that hydrophobic surfaces reduce heterogeneous nucleation, thereby delaying icing. This study introduces a mechanistic explanation for the promotion of water icing by hydrophobic surfaces and offers a novel design concept for the development of anti-ice surfaces in future applications.

3D printing has shown promise in the development of notable sensing and health detection devices. Nonetheless, challenges remain in the concurrent development of highly durable wearable sensors with low‐friction surfaces. This challenge serves as a limiting factor in the operational lifespans of these sensors. In this study, a magnetically assisted 3D printing technique is developed to fabricate composites reinforced with magnetic Fe ₃ O ₄ @SiO ₂ nanochains (NCs) with dimensions of 60.2 µm in length (L) and 0.2 µm in diameter (D), indicating an L:D ratio exceeding 300. By applying a vertical magnetic field and extrusion flow field to the sensor's surface layer, the NCs can be arranged differently (together with the printed textures), reducing the coefficient of friction by 27.7% and improving the wear resistance. This approach is inspired by nacre, known for its impressive durability and resilience. A motion monitoring sensor with an extended lifespan is successfully fabricated by using liquid metal ink integrated with an anti‐wear layer. These findings offer significant insights into the evolution of wearable sensors, demonstrating their adaptability to multi‐material printing and resulting in improved performance and service lives.

The transverse skin of dolphins exhibits a remarkable drag reduction effect. Although previous studies have identified the drag reduction effect of transverse grooves, no clear guidelines exist regarding the impact of groove parameters on turbulent drag reduction. Hence, this paper suggests a novel numerical study using the Reynolds-averaged Navier–Stokes method to investigate the influence of half-sine wave structure parameters on turbulent drag. The results showed that the aspect ratio of shape parameters significantly affected the drag reduction rate by altering the flow velocity and drag distribution near the wall and increasing the viscous sublayer thickness. Moreover, a novel index friction pressure ratio FPr was introduced to evaluate the drag reduction. It was revealed that the ratio FPr was stable at optimal drag reduction effect regardless of the velocity. By optimizing the FPr, a maximum drag reduction of 29.3% was achieved. These findings provide insight for optimizing transverse groove in drag-reducing surface applications.

In recent years, the manufacturing environment has undergone a significant transformation, resulting in a shift towards factory intelligence and informatization. This change has led to a deep integration of traditional manufacturing technology and information technology. Digital twin technology plays a crucial role in achieving a seamless interaction between the physical and information world, facilitating the analysis and optimization of physical models through the exploration of twins. Despite the many theoretical achievements in digital twin, few practical application cases have been implemented to date. This paper focuses on the assembly unit of the sub-array bus bar automatic welding robot, delving into the modeling and simulation control issues of the assembly unit as a point of entry. Furthermore, we investigate the virtual simulation and virtual-real mapping of the assembly unit based on relevant digital twinning theories and demonstrate how physical and information models interact with signals in real-time.

Flexible materials with ideally designed structures and properties through direct ink writing (DIW) offer vast potential for flexible wearable devices, sensors, soft robots, and so on. Despite its common use as a flexible material, Sylgard‐184's poor rheological properties restrict its ability of printing precision models by DIW. Herein, we have improved the viscosity of Sylgard‐184 by adding suitable crosslinkers and silica, which produce inks with high printing quality and a low slump rate (3.75%). In addition, the DIW printing process was investigated, and a theoretical model relating to the basic printing parameters was developed. With the model, it is possible to predict printing parameters for various elastomers. To further demonstrate the application of this strategy to flexible wearable devices, a sensor was printed. The sensor allowed real‐time monitoring of bending angles through bending angle tests. A change from 0 to 135° was detected using this bending sensor. We believe that the results of this research will provide ideas for the high‐quality printing of silicone elastomers.