Integrating metals and plastics is essential for lightweight structures and efficient assembly in industries such as automotive and IT device manufacturing. This study investigated how laser micro-patterning enhances the interfacial bonding strength between these dissimilar materials in metal insert injection molding. Galvanized high-strength steel and polyphenylene sulfide (PPS) reinforced with 40% glass fiber were used as the metal and plastic materials, respectively. Four micro-patterns—circular, square, diamond, and hexagonal—were machined by laser on the bonding area at the end of the steel sheet. The effect of pattern spacing on bonding strength was evaluated by tensile shear tests on injection-molded specimens. The combined effect of laser processing and plasma surface treatment was also examined. For the square pattern, wider pattern spacing increased the bonding strength 2.2-fold, and for the hexagonal pattern the increase was 1.4- fold. Combining laser micro-patterning with plasma treatment enhanced the bonding strength by factors of 1.4 to 2.3. The effect of plasma treatment was greater for the square and diamond patterns than for the circular geometry.

Purification of water through oil–water separation is essential for preserving the ecosystem and protecting human health. Although a conventional polypropylene depth filter can effectively purify water, modifying the wettability of a filter for oil–water separation is difficult owing to its low reactivity. In this study, we developed a superhydrophilic polypropylene filter with a hydrogel layer that could enable effective oil–water separation by using plasma treatment and dip coating, which enabled an even distribution of the coating solution across the filter. The fabricated filter was superhydrophilic with a water contact angle of 0o. It showed a high repulsive force with oil in water with an underwater oil contact angle of 142.9o. When such filter was applied to an oil–water separation device, it effectively purified water with low oil content (< 15 ppm) at a flow rate of 300 mL/min. These results demonstrate potential applications of such filters in areas such as wastewater treatment and oil spill cleanup.

High-k dielectric thin films are widely applied in energy conversion/storage and information storage devices such as Dynamic Random access Memory (DRAM), Multilayer Ceramic Capacitor (MLCC), thermoelectric devices, etc. Among them, perovskite thin films, for instance, strontium titanate (STO) and barium titanate (BTO) are known to have extremely superior dielectric properties. Atomic layer deposition (ALD), can deposit thin films through atomic layering producing uniform and conformal high-k thin films with precise thickness control. While relatively low crystallinity of film quality due to low deposition temperatures of ALD can develop practical issues, they can be overcome by employing additional processes such as thermal annealing, plasma treatment, and seed layering. ALD, STO and BTO thin films treated with these additional processes demonstrate more improved crystallinity and electrical properties. In this paper, the processes to enhance properties of ALD high-k thin films, BTO and STO films are reviewed. Perspectives into high quality ALD high-k thin films as well as current efforts to further improve the film quality are discussed.