Surface Quality and Mechanical Property Control of Laser Powder Bed Fusion Additively Manufactured Ti–6Al–4V Hollow‐Strut Lattice Metamaterials

To achieve lightweight and enhanced mechanical performance of titanium alloy lattice structures, this study employed laser powder bed fusion (L‐PBF) technology integrated with an ultrasonic‐assisted chemical cleaning and sandblasting composite post‐processing technique to fabricate high‐quality, high‐porosity hollow‐strut lattice metamaterials. By regulating the topologies of BCC, BCCZ, and BCC‐CZ topological configurations, the mechanical properties are systematically tailored. The mechanical behavior and energy absorption characteristics are investigated through finite element simulations combined with uniaxial compression experiments. Results indicate that the hollow‐strut design significantly enhances the mechanical performance, with the BCCZ‐H configuration exhibiting optimal properties: compressive strength of 174.91 MPa and elastic modulus of 3550 MPa, representing improvements of 25% and 75%, respectively, over the BCCZ solid pillar lattice structure. At 40% compressive strain, its energy absorption reaches 2.3 times that of the solid lattice. Furthermore, fracture mechanism analysis revealed that the hollow design facilitates a transition from brittle to ductile failure modes. This study presents a promising methodology for the development of lightweight metamaterials with superior strength and toughness.