The contribution of 515-nm green laser L-PBF to the thermal performance of lattice-based heat exchangers for hydrogen storage applications

This paper presents a study on the thermal and electrical performance of lattice structures designed for a heat exchanger, where the geometry is optimized for enhanced heat management through a numerical simulation scheme based on the response surface method. The goal was to achieve effective heat conduction and convection. Lattice structures were selected for their inherent porosity, enabling efficient heating and cooling cycles. The optimized lattice geometry was fabricated using Laser powder bed fusion (L-PBF) additive manufacturing, with a “green” laser emission wavelength (λ = 515 nm) to improve energy absorption and final product density. Experimental evaluations assessed the thermal and electrical performance of the L-PBF-produced samples, including both workpieces and lattice structures designed for additive manufacturing. Microscopic and microstructural studies were conducted to identify potential manufacturing defects, such as porosities and cracks, resulting from the L-PBF process. Despite some defects persisting in certain lattice structures, the results showed significant improvements in both thermal and electrical properties compared to those obtained using the traditional infrared laser L-PBF process. An enhanced 3D-printed heat exchanger design is proposed, emphasizing lattice-like internal structures. This advancement offers superior control, increased durability, and improved safety for hydrogen storage devices. This research represents a significant contribution to the field of heat exchanger design and additive manufacturing, especially in the context of hydrogen storage technologies. It demonstrates the potential for lattice structures and innovative manufacturing processes to revolutionize the efficiency and safety of thermal systems.