Additively manufactured mesh-type titanium structures for cranial implants: E-PBF vs. L-PBF

Materials & Design

Ingmar Fleps¹  Stephen J. Ferguson²  Susanne Lewin²  Benedikt Helgason²  Caroline Öhman-Mägi²  Håkan Engqvist³  Cecilia Persson³  Jonas Åberg³ 

[1] Corresponding author at: Div. of Applied Materials Science, Dept. of Materials Science and Engineering Sciences, Uppsala University, Box 35, 751 03 Uppsala, Sweden.;Div. of Applied Materials Science, Dept. of Materials Science and Engineering Sciences, Uppsala University, Uppsala, Sweden;Institute for Biomechanics, ETH Zurich, Zurich, Switzerland;

关键词: Additive manufacturing;    Electron beam melting;    Powder bed fusion;    Finite element models;    Surface roughness;    Cranial implant;   

DOI  :  

来源: DOAJ

【 摘 要 】

A patient-specific titanium-reinforced calcium phosphate (CaP–Ti) cranial implant has recently shown promising clinical results. Currently, its mesh-type titanium structure is additively manufactured using laser beam powder bed fusion (L-PBF). Nevertheless, an electron-beam (E-PBF) process could potentially be more time efficient. This study aimed to compare the geometrical accuracy and mechanical response of thin titanium structures manufactured by L-PBF (HIPed) and E-PBF (as-printed). Tensile test (ø = 1.2 mm) and implant specimens were manufactured. Measurements by μCT revealed a deviation in cross-sectional area as compared to the designed geometry: 13–35% for E-PBF and below 2% for L-PBF. A superior mechanical strength was obtained for the L-PBF specimens, both in the tensile test and the implant compression tests. The global peak load in the implant test was 457 ± 9 N and 846 ± 40 N for E-PBF and L-PBF, respectively. Numerical simulations demonstrated that geometrical deviation was the main factor in implant performance and enabled quantification of this effect: 34–39% reduction in initial peak force based on geometry, and only 11–16% reduction based on the material input. In summary, the study reveals an uncertainty in accuracy when structures of sizes relevant to mesh-type cranial implants are printed by the E-PBF method.

【 授权许可】

Unknown