TY - JOUR
T1 - Multiscale modeling of fatigue crack propagation in additively manufactured porous biomaterials
AU - Hedayati, R.
AU - Hosseini-Toudeshky, H.
AU - Sadighi, M.
AU - Mohammadi-Aghdam, M.
AU - Zadpoor, A. A.
N1 - Accepted Author Manuscript
PY - 2018
Y1 - 2018
N2 - Advances in additive manufacturing (AM) techniques have enabled fabrication of highly porous titanium implants that combine the excellent biocompatibility of bulk titanium with all the benefits that a regular volume-porous structure has to offer (e.g. lower stiffness values comparable to those of bone). Clinical application of such biomaterials requires thorough understanding of their mechanical behavior under loading. Computational models have been therefore developed by various groups for prediction of their quasi-static mechanical properties. The fatigue behavior of AM porous biomaterials is, however, not well understood. In particular, computational models predicting the fatigue response of these structures are rare. That is primarily due to the fact that geometrical features present in computational model of fully porous structures span over multiple length scales. This makes the problem formidably expensive to solve computationally. Here, we propose a multi-scale modeling approach to alleviate this problem and solve the problem of crack propagation in AM porous biomaterials. In this approach, the area around the crack tip is modelled at the micro-scale (using beam elements) while the area far from the crack tip is modeled at the macro-scale (using volumetric elements). Compact-tension notched specimens were fabricated using a selective laser melting machine for validating the results of the presented modeling approach. The multi-scale computational model was found to be capable of predicting the fatigue response observed in experiments.
AB - Advances in additive manufacturing (AM) techniques have enabled fabrication of highly porous titanium implants that combine the excellent biocompatibility of bulk titanium with all the benefits that a regular volume-porous structure has to offer (e.g. lower stiffness values comparable to those of bone). Clinical application of such biomaterials requires thorough understanding of their mechanical behavior under loading. Computational models have been therefore developed by various groups for prediction of their quasi-static mechanical properties. The fatigue behavior of AM porous biomaterials is, however, not well understood. In particular, computational models predicting the fatigue response of these structures are rare. That is primarily due to the fact that geometrical features present in computational model of fully porous structures span over multiple length scales. This makes the problem formidably expensive to solve computationally. Here, we propose a multi-scale modeling approach to alleviate this problem and solve the problem of crack propagation in AM porous biomaterials. In this approach, the area around the crack tip is modelled at the micro-scale (using beam elements) while the area far from the crack tip is modeled at the macro-scale (using volumetric elements). Compact-tension notched specimens were fabricated using a selective laser melting machine for validating the results of the presented modeling approach. The multi-scale computational model was found to be capable of predicting the fatigue response observed in experiments.
KW - Additive manufacturing
KW - Fatigue properties
KW - Multi-scale model
KW - Numerical modeling
KW - Porous biomaterial
UR - http://resolver.tudelft.nl/uuid:57dcd88b-c04f-400c-af58-709f03a6bd95
UR - http://www.scopus.com/inward/record.url?scp=85046707575&partnerID=8YFLogxK
U2 - 10.1016/j.ijfatigue.2018.05.006
DO - 10.1016/j.ijfatigue.2018.05.006
M3 - Article
AN - SCOPUS:85046707575
SN - 0142-1123
VL - 113
SP - 416
EP - 427
JO - International Journal of Fatigue
JF - International Journal of Fatigue
ER -