Compressive Properties of Functionally Graded Bionic Bamboo Lattice Structures Fabricated by FDM

Area of Science:

• Materials Science and Engineering
• Mechanical Engineering
• Biomimetics and Bionic Design

Background:

• Lattice structures are crucial in various engineering applications due to their high strength-to-weight ratio.
• Bionic design principles offer a pathway to enhance the mechanical performance and energy absorption capabilities of engineered materials.
• Previous research has explored various unit cell designs, but the integration of bionic concepts with functionally graded properties remains an active area of investigation.

Purpose of the Study:

• To design and fabricate bamboo-inspired bionic lattice structures with graded strut diameters using 3D printing.
• To investigate the effects of unit cell design (cubic, honeycomb, bionic bamboo) and structural grading on mechanical properties and energy absorption.
• To compare the performance of functionally graded lattice structures against their uniform counterparts.

Main Methods:

• Design of cubic, honeycomb, and bamboo-inspired lattice structures with uniform and functionally graded strut diameters.
• Additive manufacturing (3D printing) for fabricating the designed lattice structures.
• Quasi-static compression testing to evaluate mechanical properties, energy absorption, and deformation modes.

Main Results:

• The bionic bamboo lattice structure demonstrated comparable mechanical properties and energy absorption to the honeycomb structure, outperforming the cubic structure.
• Functionally graded lattice structures exhibited superior initial peak strength, compressive modulus, and energy absorption compared to uniform lattice structures.
• The study identified specific deformation modes influenced by unit cell geometry and grading strategy.

Conclusions:

• Bionic design, particularly the bamboo-inspired approach, is effective in enhancing lattice structure performance.
• Functionally graded designs significantly improve key mechanical characteristics and energy absorption of 3D-printed lattice structures.
• The findings support the use of bionic and functionally graded principles for developing advanced lattice materials with tailored properties.