Mechanical properties and microstructure characteristics of lattice-surfaced PEEK cage fabricated by high-temperature laser powder bed fusion

Porous structure design on the contact surface is crucial to promote the osseointegration of the interver-tebral cage while preventing subsidence and displacement. However, the stress response will undergo sig-nificant changes for the current random porous cages, which can directly affect the mechanical properties and long-term usability. Here, this paper proposed a newly designed polyetheretherketone (PEEK) cage with the triply periodic minimal surface (TPMS)-structured lattice surfaces to provide tailored 3D mi-croporosity and studied the mechanical performance, stress/strain responses, and microstructure changes in depth. The lattice-surfaced PEEK cage mainly exhibits a multiple-point-plane stress transfer mecha-nism. The compression modulus and elastic limit can be adjusted by controlling the area of the Diamond TPMS surface while the energy absorption efficiency remains stable. The microstructure of high-strength PEEK is featured by the radial pattern morphology. Meanwhile, the double-stranded orthorhombic phase is more ordered, and the benzene plane subunit and lattice volume become more expanded. (c) 2022 Published by Elsevier Ltd on behalf of The editorial office of Journal of Materials Science & Technology.

Automated summary

This paper proposes a newly designed PEEK cage with lattice surfaces based on TPMS structure to provide tailored 3D microporosity, and studies its mechanical performance and microstructure changes. The cage exhibits a multiple-point-plane stress transfer mechanism, and the compression modulus and elastic limit can be adjusted.