Perpustakaan Digital ITB

This study investigates the compressive behavior of graded and non-graded double arrowhead auxetic lattice structures under quasi-static and high strain rate loading, focusing on the effects of geometric grading, loading rate, and UV post-curing. Six configurations were fabricated from Phrozen Aqua 8K photopolymer resin using vat photopolymerization. All configurations were tested under quasi-static compression, while four representative configurations were further evaluated using a Split Hopkinson Pressure Bar at striker velocities of 5, 10, and 15 m/s. The graded thickness configuration was also examined after UV post-curing for 0, 5, and 15 minutes. The results show that geometry, loading rate, and curing condition strongly influenced the mechanical response. Under quasi-static compression, the non-graded t? configuration exhibited the highest effective elastic modulus, maximum stress, and volumetric energy absorption. A 15-minute UV post-curing treatment further improved the stiffness and volumetric energy absorption of the graded thickness specimen. Under high strain rate loading, the non-graded ?? configuration achieved the highest ultimate compressive strength, whereas the graded angle configuration showed the greatest volumetric energy absorption. Compared with quasi-static compression, dynamic compression produced higher stress at low strain but resulted in a shorter and less progressive collapse process. Overall, the findings indicate that different grading strategies offer distinct advantages depending on the loading condition. These results support the development of additively manufactured auxetic lattice structures for lightweight energy absorbing applications under quasi-static and impact loading.