Field-driven design and performance evaluation of dual functionally graded triply periodic minimal surface structures for additive manufacturing

Abstract

Triply periodic minimal surface (TPMS) structures prepared by additive manufacturing (AM) have been widely used in aerospace and thermal management systems due to their functional advantages such as high specific strength and excellent heat transfer coefficient. However, lattices with uniform or simple gradients cannot match the regional diversity needs of functional advantages in service. This study proposed a field-driven AM data processing framework for dual functionally graded TPMS lattices. For unified data processing, mathematical functions, simulated outcomes, and geometric models were transformed into fields. I-WP and Diamond units were selected as the primitive and filling structures of Ti-6Al-4V lattices, respectively. According to the functional requirements, the gradient distribution design guided by the simulated stress field is completed through the proposed framework. The results illustrate that the field-driven dual graded lattices present superior compressive mechanical response. At almost equal volume fractions, their compressive strength is approximately 100% more than that of primitive lattices and 69% greater than that of dual uniform lattices. Furthermore, the dual lattices have larger specific surface areas than the primitive lattices, making them better at heat insulation and heat dissipation. This field-driven digital framework will show enormous potential in the matching design of functionally graded lattices.

Keywords

• Additive manufacturing
• Functionally graded lattices
• Triply periodic minimal surface (TPMS)
• Ti-6Al-4V