In this study, we present the energy absorption capabilities achieved through the application of hybrid lattice structures, emphasizing their potential across various industrial sectors. Utilizing Ti-6Al-4V and powder bed fusion (PBF) techniques, we fabricated distinct octet truss, diamond, and diagonal lattice structures, tailoring each to specific densities such as 10, 30, and 50%. Furthermore, through the innovative layering of diverse lattice types, we introduced hybrid lattice structures that effectively overcome the inherent energy absorption limitations of single-lattice structures. As a result, we conducted a comprehensive comparison between single-lattice structures and hybrid lattice structures of equal density, unequivocally showcasing the latter’s superior energy absorption performance in terms of compression. The single-lattice structure, OT, showed an energy absorption of 42.6 J/m3, while the reinforced hybrid lattice structure, OT-DM, represented an energy absorption of 77.8 J/m3. These findings demonstrate the significant potential of hybrid lattice structures, particularly in energy-intensive domains such as shock absorption structures. By adeptly integrating various lattice architectures and leveraging their collective energy dissipation properties, hybrid lattice structures offer a promising avenue for addressing energy absorption challenges across diverse industrial applications.
4 March 2024 in International Journal of Precision Engineering and Manufacturing
This study investigates the reduction in thermal residual stress during the powder bed fusion (PBF) process in a non-standardized shape generated by topology optimization method in lightweight automotive part of brake caliper. While the caliper of the braking system for reducing the CO2 consumption in vehicle systems undergoes a redesign to increased strength and reduced weight, challenges arise due to biased melting area ratios in the topologically optimized design, causing the thermal deformation. To address this, our research proposes an efficient PBF scan strategy aimed at minimizing anisotropy and residual stress—a critical consideration for successful manufacturing. The effectiveness of the laser scan strategy is validated through testing on a brake dynamometer, following the JASO C406 test procedure, an authorized standard for commercial brake calipers. Furthermore, a comparative analysis between the conventional product and the proposed brake caliper highlights superior performance, particularly under lightweight conditions. This comprehensive approach contributes valuable insights to the field, offering a potential solution for overcoming manufacturing challenges associated with topologically optimized designs in automotive components.
This study investigates the design of additive manufacturing for controlled crack propagation using process parameters and lattice structures. We examine two lattice types—octet-truss (OT) and diamond (DM)—fabricated via powder bed fusion with Ti-6Al-4V. Lattice structures are designed with varying densities (10%, 30%, and 50%) and process using two different laser energies. Using additive-manufactured specimens, Charpy impact tests are conducted to evaluate the fracture behavior and impact energy levels of the specimens. Results show that the type of the lattice structures, the density of the lattice structures, and laser energy significantly influence crack propagation patterns and impact energy. OT exhibits straighter crack paths, while DM demonstrates more random fracture patterns. Higher-density lattices and increased laser energy generally improve the impact energy. DM consistently outperformed OT in the impact energy for angle specimens, while OT showed superior performance in stair specimens. Finally, a case study demonstrates the potential for combining OT and DM structures to guide crack propagation along predetermined paths, offering a novel approach to protect critical components during product failure.