Effects of the unit cell topology on the compression properties of porous Co-Cr scaffolds fabricated via selective laser melting

Emerald - Tập 23 Số 1 - Trang 16-27 - 2017
Changjun Han1, Chunze Yan1, Shifeng Wen1, Tian Xu1, Shuai Li1, Jie Liu1, Qingsong Wei1, Yusheng Shi1
1State Key Lab of Materials Processing and Die and Mould Technology, Huazhong University of Science and Technology, Wuhan, China

Tóm tắt

Purpose Selective laser melting (SLM) is an additive manufacturing process suitable for fabricating metal porous scaffolds. The unit cell topology is a significant factor that determines the mechanical property of porous scaffolds. Therefore, the purpose of this paper is to evaluate the effects of unit cell topology on the compression properties of porous Cobalt–chromium (Co-Cr) scaffolds fabricated by SLM using finite element (FE) and experimental measurement methods. Design/methodology/approach The Co-Cr alloy porous scaffolds constructed in four different topologies, i.e. cubic close packed (CCP), face-centered cubic (FCC), body-centered cubic (BCC) and spherical hollow cubic (SHC), were designed and fabricated via SLM process. FE simulations and compression tests were performed to evaluate the effects of unit cell topology on the compression properties of SLM-processed porous scaffolds. Findings The Mises stress predicted by FE simulations showed that different unit cell topologies resulted in distinct stress distributions on the bearing struts of scaffolds, whereas the unit cell size directly determined the stress value. Comparisons on the stress results for four topologies showed that the FCC unit cell has the minimum stress concentration due to its inclined bearing struts and horizontal arms. Simulations and experiments both indicated that the compression modulus and strengths of FCC, BCC, SHC, CCP scaffolds with the same cell size presented in a descending order. These distinct compression behaviors were correlated with the corresponding mechanics response on bearing struts. Two failure mechanisms, cracking and collapse, were found through the results of compression tests, and the influence of topological designs on the failure was analyzed and discussed. Finally, the cell initial response of the SLM-processed Co-Cr scaffold was tested through the in vitro cell culture experiment. Originality/value A focus and concern on the compression properties of SLM-processed porous scaffolds was presented from a new perspective of unit cell topology. It provides some new knowledge to the structure optimization of porous scaffolds for load-bearing bone implants.

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Tài liệu tham khảo

1998, Reconstructing the human body using biomaterials, JOM, 50, 31, 10.1007/s11837-998-0064-5

2014, Mechanical behavior of regular open-cell porous biomaterials made of diamond lattice unit cells, Journal of the Mechanical Behavior of Biomedical Materials, 34, 106, 10.1016/j.jmbbm.2014.02.003

2008, Porosity and the fatigue behavior of hypoeutectic and hypereutectic aluminum-silicon casting alloys, International Journal of Fatigue, 30, 1024, 10.1016/j.ijfatigue.2007.08.012

2008, Corrosion aspects of metallic implants – An overview, Materials and Corrosion, 59, 855, 10.1002/maco.200804173

2009, Application of laser engineered net shaping (LENS) to manufacture porous and functionally graded structures for load bearing implants, Journal of Materials Science: Materials in Medicine, 20, 29

1999, Tissue response to porous tantalum acetabular cups: a canine model, The Journal of Arthroplasty, 14, 347, 10.1016/S0883-5403(99)90062-1

2012, Compression deformation behavior of Ti-6Al-4V alloy with cellular structures fabricated by electron beam melting, Journal of the Mechanical Behavior of Biomedical Materials, 16, 153, 10.1016/j.jmbbm.2012.10.005

EOS, 2006, 1

2011, Osteoinduction of porous Ti implants with a channel structure fabricated by selective laser melting, Acta Biomaterialia, 7, 2327, 10.1016/j.actbio.2011.01.037

2012, Effects of materials of cementless femoral stem on the functional adaptation of bone, Journal of Bionic Engineering, 9, 66, 10.1016/S1672-6529(11)60098-X

2013, Static mechanical behaviours of stainless steel micro-lattice structures under different loading conditions, Materials Science and Engineering: A, 586, 392, 10.1016/j.msea.2013.07.070

2013, Evaluation of the stiffness characteristics of square pore CoCrMo cellular structures manufactured using laser melting technology for potential orthopaedic applications, Materials & Design, 51, 949, 10.1016/j.matdes.2013.05.009

1983, A constitutive model and data for metals subjected to large strains, high strain rates and high temperatures, Proceedings of the 7th International Symposium on Ballistics, 21, 541

2014, Deformation behaviour of stainless steel microlattice structures by selective laser melting, Materials Science and Engineering: A, 614, 116, 10.1016/j.msea.2014.07.015

2010, Fabrication and compressive properties of Ti6Al4V implant with honeycomb-like structure for biomedical applications, Rapid Prototyping Journal, 16, 44, 10.1108/13552541011011703

2007, Structural and mechanical evaluations of a topology optimized titanium interbody fusion cage fabricated by selective laser melting process, Journal of Biomedical Materials Research Part A, 83, 272

1977, Metals in medicine and surgery, International Metals Reviews, 22, 119, 10.1179/imtr.1977.22.1.119

2009, Selective laser melting: a regular unit cell approach for the manufacture of porous, Titanium, bone in-growth constructs, suitable for orthopedic applications, Journal of Biomedical Materials Research Part B: Applied Biomaterials, 89, 325

2010, Selective laser melting: a unit cell approach for the manufacture of porous, titanium, bone in-growth constructs, suitable for orthopedic applications: II. Randomized structures, Journal of Biomedical Materials Research Part B: Applied Biomaterials, 92, 178

2010, Mechanical evaluation of porous titanium (Ti6Al4V) structures with electron beam melting (EBM), Journal of the Mechanical Behavior of Biomedical Materials, 3, 249, 10.1016/j.jmbbm.2009.10.006

2010, Investigation of high cycle and very-high-cycle fatigue behaviors for a structural steel with smooth and notched specimens, Engineering Failure Analysis, 17, 1517, 10.1016/j.engfailanal.2010.06.002

2015, Influence of processing conditions on strut structure and compressive properties of cellular lattice structures fabricated by selective laser melting, Materials Science and Engineering: A, 628, 188, 10.1016/j.msea.2015.01.031

1975, The elastic and ultimate properties of compact bone tissue, Journal of Biomechanics, 8, 393, 10.1016/0021-9290(75)90075-5

2008, Porous titanium scaffolds fabricated using a rapid prototyping and powder metallurgy technique, Biomaterials, 29, 3625, 10.1016/j.biomaterials.2008.05.032

1998, The effects of cell face curvature and corrugations on the stiffness and strength of metallic foams, Acta Materialia, 46, 3929, 10.1016/S1359-6454(98)00072-X

2013, Finite element modelling of the compressive response of lattice structures manufactured using the selective laser melting technique, International Journal of Mechanical Sciences, 67, 28, 10.1016/j.ijmecsci.2012.12.004

2013, Mechanical properties of a Ti6Al4V porous structure produced by selective laser melting, Materials & Design, 49, 545, 10.1016/j.matdes.2013.01.038

2013, Microstructures and mechanical properties of Co-29Cr-6Mo alloy fabricated by selective laser melting process for dental applications, Journal of the mechanical Behavior of Biomedical Materials, 21, 67, 10.1016/j.jmbbm.2013.01.021

2011, Micro-CT-based improvement of geometrical and mechanical controllability of selective laser melted Ti6Al4V porous structures, Materials Science and Engineering: A, 528, 7423, 10.1016/j.msea.2011.06.045

2012, The effect of pore geometry on the in vitro biological behavior of human periosteum-derived cells seeded on selective laser-melted Ti6Al4V bone scaffolds, Acta Biomaterialia, 8, 2824, 10.1016/j.actbio.2012.04.001

2013, Selective laser melting-produced porous titanium scaffolds regenerate bone in critical size cortical bone defects, Journal of Orthopaedic Research, 31, 792, 10.1002/jor.22293

2013, Study on the designing rules and processability of porous structure based on selective laser melting (SLM), Journal of Materials Processing Technology, 213, 1734, 10.1016/j.jmatprotec.2013.05.001

2008, On the mechanisms of biocompatibility, Biomaterials, 29, 2941, 10.1016/j.biomaterials.2008.04.023

2012, Evaluations of cellular lattice structures manufactured using selective laser melting, International Journal of Machine Tools and Manufacture, 62, 32, 10.1016/j.ijmachtools.2012.06.002

2015, Microstructure and mechanical properties of aluminium alloy cellular lattice structures manufactured by direct metal laser sintering, Materials Science and Engineering: A, 628, 238, 10.1016/j.msea.2015.01.063

2007, How tough is bone? Application of elastic–plastic fracture mechanics to bone, Bone, 40, 479, 10.1016/j.bone.2006.08.013

2011, Numerical investigation of the effect of porous titanium femoral prosthesis on bone remodeling, Materials & Design, 32, 1776, 10.1016/j.matdes.2010.12.042

2001, Structure, metallurgy, and mechanical properties of a porous tantalum foam, Journal of Biomedical Materials Research, 58, 180, 10.1002/1097-4636(2001)58:2<180::AID-JBM1005>3.0.CO;2-5

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Emerald

Tập 23 Số 1

16-27

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