Page 103 - ESAM-1-1

Engineering Science in
Additive Manufacturing Mechanical property of metal-based IPC

A B C

D

E

Figure 4. Schematic of mechanical mechanisms. (A-C) Comparison of engineering stress-strain curves for (A) FCC-IPC, (B) FCCR-IPC, and (C) FCCH-
IPC against corresponding Ti-6Al-4V truss of equal mass. (D and E) Illustration of mechanical responses and deformation mechanisms of (D) truss
microlattice and (E) IPC metamaterial.
Abbreviations: FCC: Face-centered cubic; FCCH: FCC vertical reinforcement truss microlattice metamaterial; FCCR: FCC hierarchical truss microlattice
metamaterial; IPC: Interpenetrating phase composite.

In contrast, IPC metamaterials effectively mitigate 4. Conclusion
buckling instability due to the presence of the ductile
epoxy resin matrix. Under compressive loading, the This study demonstrates the superior mechanical
epoxy provides additional mechanical resistance for performance of IPCs that integrate metal microlattices
supporting the rigid struts and restricting their lateral with infiltrating epoxy resin. By designing and fabricating
deformation. This resistance prevents unstable buckling, FCC, FCCR, and FCCH truss lattices using SLM and
as illustrated in Figure 4E-ii and iii, allowing the rigid subsequently infiltrating epoxy resin, we developed IPC
struts to deform uniformly under strain. Furthermore, metamaterials with notable improvements in strength
the complex interactions between the struts and the epoxy and energy absorption capacity synergistically. Our
introduce mixed deformation mechanisms – stretching, experimental results revealed that IPC metamaterials
bending, and shearing – that synergistically redistribute exhibited progressive collapse behavior under compressive
and optimize stress throughout the structure, thereby loading, effectively mitigating the catastrophic collapse
delaying the onset of localized failure. More importantly, observed in pure truss lattices. This progressive collapse is
this synergy between the rigid truss microlattice and the characterized by a stable plateau region in the stress-strain
ductile epoxy resin enables IPC metamaterials to overcome curves, enabling IPCs to maintain compressive loads over
the traditional trade-off between strength and toughness, a broad strain range.
achieving a unique balance in which both properties are Quantitatively, the compressive strength of IPC
simultaneously enhanced. metamaterials surpassed the linear combination of

Volume 1 Issue 1 (2025) 8 doi: 10.36922/esam.8554