Bingwen Lu

Traditional C276 alloy plates exhibit relatively poor wear resistance. Consequently, in high-wear service environments, they typically require reinforcement through additional surface coatings or wear-resistant materials. To further expand the application potential of C276 alloy in marine environments, where both corrosion resistance and wear resistance are critical, this study utilized L-PBF technology to fabricate C276 alloy specimens. The specimens were subjected to microhardness, room-temperature tensile, electrochemical corrosion, and tribological wear tests under three distinct heat treatment conditions. The results indicate that the precipitation of a Mo/W-rich μ-phase, induced by heat treatment, serves as the key factor in tailoring the material’s properties. Heat treatment was found to significantly enhance both the corrosion resistance and wear resistance of the L-PBF–fabricated C276 alloy. Specifically, the heat treatment process involving holding at 870 °C for 8 h followed by furnace cooling demonstrated the most effective strengthening effect. Under these conditions, both the microhardness and tensile strength were markedly higher than those of traditional plate specimens, thereby significantly improving the material’s damage resistance. Furthermore, the primary wear mechanisms observed in the specimens were adhesive wear and abrasive wear, accompanied by minor oxidative wear. Compared to traditional plate material, the wear rate of the heat-treated L-PBF C276 alloy was significantly reduced. This study demonstrates that appropriate heat treatment processes provide an effective pathway for tailoring the properties of L-PBF–fabricated C276 alloy components, a finding of significant importance for extending their service life and expanding their engineering applications.

Hydrogen is an ideal feedstock fuel for solid oxide fuel cells (SOFCs). The steam reforming of methane (SRM) is the predominant method of producing hydrogen. However, the process of SRM relies on the involvement of a catalyst, and the reforming efficiency is constrained by the limited surface area in the traditional catalyst system. In this study, a mixer structure is applied to improve the mixing of the methane. Nano-sized pores are introduced to the struts of the mixer structure, forming a hierarchical structure, to effectively reduce the weight and increase the surface area of the self-catalytic reactors, hence increasing the catalytic efficiency. The hierarchical structure increases the reforming efficiency at all temperatures, and the level of improvement reaches its peak when the conversion rate of methane increases by 192% at 800 °C and by 40% at 900 °C compared to the self-catalyst without a hierarchical structure.

The specific surface area, porosity, and mechanical properties of a catalyst are critical factors that significantly influence its performance. However, conventional preparation techniques are incapable of optimizing these properties simultaneously. Here, we present the performance of three kinds of catalysts with different geometric structures. Our findings indicated that the porosity, specific surface area, and mechanical properties of the 3D-printed catalysts achieved an optimal balance, exhibiting enhanced catalytic efficiency and mechanical integrity compared to commercial catalysts. Furthermore, the excellent ductility of the metal catalyst supports effectively prevented catalyst pulverization caused by carbon deposition and the thermal expansion of the supports. These results demonstrate that 3D printing technology can open up novel avenues for catalyst preparation, especially for metal-supported catalysts. The potential of metal additive manufacturing in chemical engineering is substantial, promising transformative advancements in the design and fabrication of catalytic converters and reactors.

Improving the current-carrying friction and wear resistance of copper alloy current-carrying friction subsets effectively is a hot topic. In this paper, a method of preparing high melting point molybdenum-based coating on copper alloy surfaces by laser cladding technology is presented. A large current (106 A/m2) comparison experiment is carried out with a self-made current-carrying friction device, and the failure mechanism is analyzed. The results show that the molybdenum-based coating significantly improves the adhesion problem between the friction partner and the copper alloy substrate, while the thickness of the stress layer caused by the current-carrying friction is reduced by about 7 times. The molybdenum-based coating significantly reduces the surface arc rate and has a lower friction interface temperature, thus retaining the Al2O3 self-lubricating phase. The research in this paper is expected to provide extended research ideas for the surface protection of current-carrying friction subsets of copper alloys.