Tantalum (Ta) has excellent prospects in the bone-implant field due to its satisfactory biocompatibility. Two novel Ta lattice structures were designed and printed by selective laser melting (SLM), including the imitation saddle surface (ISS) and the imitation arch bridge telescopic (IABT) structures. Quasi-static compression tests and finite element analysis were adopted to investigate the effects of design parameters on the mechanical properties, deformation modes, and energy absorption of lattice structures. Compared with the typical lattice structure body-centred cubic (BCC) structure, the ISS lattice structure had a higher yield-stress-to-elastic-modulus ratio, and the IABT lattice structure had higher energy absorption. The failure mode of the BCC and ISS lattice structures was shear band formation. The IABT lattice structure showed hierarchical deformation during compression and collapsed with vertical strut buckling. The results indicated that the ISS lattice is the most potential candidate for bone implant applications.

Three-dimensional printing technology has fundamentally revolutionized the product development processes in several industries. Three-dimensional printing enables the creation of tailored prostheses and other medical equipment, anatomical models for surgical planning and training, and even innovative means of directly giving drugs to patients. Polymers and their composites have found broad usage in the healthcare business due to their many beneficial properties. As a result, the application of 3D printing technology in the medical area has transformed the design and manufacturing of medical devices and prosthetics. Polymers and their composites have become attractive materials in this industry because of their unique mechanical, thermal, electrical, and optical qualities. This review article presents a comprehensive analysis of the current state-of-the-art applications of polymer and its composites in the medical field using 3D printing technology. It covers the latest research developments in the design and manufacturing of patient-specific medical devices, prostheses, and anatomical models for surgical planning and training. The article also discusses the use of 3D printing technology for drug delivery systems (DDS) and tissue engineering. Various 3D printing techniques, such as stereolithography, fused deposition modeling (FDM), and selective laser sintering (SLS), are reviewed, along with their benefits and drawbacks. Legal and regulatory issues related to the use of 3D printing technology in the medical field are also addressed. The article concludes with an outlook on the future potential of polymer and its composites in 3D printing technology for the medical field. The research findings indicate that 3D printing technology has enormous potential to revolutionize the development and manufacture of medical devices, leading to improved patient outcomes and better healthcare services.

Single-component materials and homogeneous structures cannot adequately meet the various demands of ideal bone implants. Therefore, the use of three dimensional (3D) printing to form multi-materials and composites has received considerable attention owing to its potential to achieve multiple functions and properties in different areas. In this study, composite structures of polyetheretherketone (PEEK) and carbon-fibre-reinforced polyetheretherketone (CFR-PEEK) materials were designed and printed. Compression experiments were conducted to investigate the effects of the building orientation on the compression strength and failure mode. Micro-X-ray detection was conducted to observe the specimen's internal microstructures. Full-field strain monitoring was performed to measure the strain fields of the specimens. The results showed that the building orientation had a significant influence on the interface bonding quality and failure modes of the specimens. The Flat specimen exhibited the lowest compressive strength of 69.1 MPa because of the poor fusion of the bottom interface. The On-edge specimen showed a higher strength of 71.5 MPa, and interlayer tearing was the main failure mode. The Up-right specimen exhibited the largest compressive strength of 80.4 MPa. After applying the interlayer inset and in-layer inset methods, the compressive strengths of the Up-right specimen improved by 16.4% and 37.4% respectively. GRAPHICAL ABSTRACT