Engineering the elastic modulus of NiTi cellular structures fabricated by selective laser melting

Purpose This study aims to focus on the optimized design and mechanical properties of gradient triply periodic minimal surface cellular structures manufactured by selective laser melting. Design/methodology/approach Uniform and gradient IWP and primitive cellular structures have been designed by the optimized function in MATLAB, and selective laser melting technology was applied to manufacture these cellular structures. Finite element analysis was applied to optimize the pinch-off problem, and compressive tests were carried out for the evaluation of mechanical properties of gradient cellular structures. Findings Finite element analysis shows that the elastic modulus of IWP increased as design parameter b increased, and then decreased when parameter b is higher than 5.5. The highest elastic modulus of primitive increased by 89.2% when parameter b is 6. The compressive behavior of gradient IWP and primitive shows a layer-by-layer way, and elastic modulus and first maximum compressive strength of gradient primitive are higher than that of gradient IWP. The effective energy absorption of gradient cellular structures increased as the average porosity decreased, and the effective energy absorption of gradient primitive is about twice than that of gradient IWP. Originality/value This paper presents an optimized design method for the pinch-off problem of gradient triply periodic minimal surface cellular structures.

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Implant surface design for improved implant stability – A study on Ti6Al4V dense and cellular structures produced by Selective Laser Melting

Tribology International ◽

10.1016/j.triboint.2018.08.012 ◽

2019 ◽

Vol 129 ◽

pp. 272-282 ◽

Cited By ~ 12

Author(s):

F. Bartolomeu ◽

M.M. Costa ◽

J.R. Gomes ◽

N. Alves ◽

C.S. Abreu ◽

...

Keyword(s):

Selective Laser Melting ◽

Cellular Structures ◽

Implant Stability ◽

Laser Melting ◽

Implant Surface ◽

Surface Design

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Fracture behavior of cellular structures obtained by selective laser melting

Diagnostics Resource and Mechanics of materials and structures ◽

10.17804/2410-9908.2020.4.035-047 ◽

2020 ◽

pp. 35-47

Author(s):

I. S. Kamantsev ◽

◽

Yu. N. Loginov ◽

S. V. Belikov ◽

S. I. Stepanov ◽

...

Keyword(s):

Cyclic Loading ◽

Selective Laser Melting ◽

Fatigue Fracture ◽

Fracture Resistance ◽

Cellular Structure ◽

Fracture Behavior ◽

Cellular Structures ◽

Laser Melting ◽

Cellular Architecture ◽

Fatigue Fracture Resistance

An example of samples with a cellular architecture, obtained by selective laser melting, is used to study the influence of the building direction of cellular objects on the characteristics of fracture under cyclic loading. The origin of their fracture has been revealed. The mechanism providing increased fatigue fracture resistance of objects which, along with the cellular structure, have anisotropy of properties due to the technological features of their production has been determined.

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Influence of specimen size on the mechanical properties of microlattices obtained by selective laser melting

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406219869741 ◽

2019 ◽

pp. 095440621986974

Author(s):

Matteo Gavazzoni ◽

Laura Boniotti ◽

Stefano Foletti

Keyword(s):

Elastic Modulus ◽

Selective Laser Melting ◽

Test Procedure ◽

Specimen Size ◽

The Body ◽

Image Correlation ◽

Good Prediction ◽

Face Centered Cubic ◽

Body Centered Cubic ◽

Laser Melting

A detailed study of compression tests on lattice structures obtained by selective laser melting with AlSi7Mg powder is presented here. Two different cell topologies have been investigated: the body-centered cubic cell and the face centered cubic cell or 3D Warren structure. Specimens of different volume have been printed in order to investigate the effect of the size on the mechanical response and properties of the structure. Particular attention has been paid to the definition of the test procedure and the analysis of the data to properly characterize the microlattice. No remarkable effect of the specimen size has been found in terms of elastic modulus and yielding stress. On the contrary, the maximum stress and the failure mechanism are influenced by the size of the specimen; for the body-centered cubic cell, a detailed analysis has been performed through digital image correlation of the failure. Test results have been compared with the results of an elasto-plastic simulation performed on a single cell of lattice with periodic boundary conditions, showing a good prediction in terms of elastic modulus and yielding stress.

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Comparison of different cellular structures for the design of selective laser melting parts through the application of a new lightweight parametric optimisation method

Journal of Zhejiang University SCIENCE A ◽

10.1631/jzus.a1800422 ◽

2019 ◽

Vol 20 (2) ◽

pp. 117-132 ◽

Cited By ~ 2

Author(s):

Rubén Paz ◽

Mario D. Monzón ◽

Philippe Bertrand ◽

Alexey Sova

Keyword(s):

Selective Laser Melting ◽

Cellular Structures ◽

Laser Melting ◽

Parametric Optimisation

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Investigation of the influence of geometry and technological parameters of production on the structure and properties of spherical cellular structures obtained by selective laser melting

Journal of Physics Conference Series ◽

10.1088/1742-6596/1109/1/012043 ◽

2018 ◽

Vol 1109 ◽

pp. 012043

Author(s):

A Y Travyanov ◽

P V Petrovskiy ◽

V V Cheverikin ◽

P Yu Sokolov ◽

A A Davidenko

Keyword(s):

Selective Laser Melting ◽

Cellular Structures ◽

Structure And Properties ◽

Technological Parameters ◽

Laser Melting

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Influence of Scanning on Nano Crystalline β-Ti Alloys Fabricated by Selective Laser Melting and Their Applications in Biomedical Science

Journal of Nanoscience and Nanotechnology ◽

10.1166/jnn.2020.17340 ◽

2020 ◽

Vol 20 (3) ◽

pp. 1605-1612 ◽

Cited By ~ 5

Author(s):

Lamei Yan ◽

Jianghong Yu ◽

Yuxing Zhong ◽

Yan Gu ◽

Yunpeng Ma ◽

...

Keyword(s):

Mechanical Properties ◽

Elastic Modulus ◽

Selective Laser Melting ◽

Biomedical Science ◽

The Novel ◽

Laser Melting ◽

Bioactive Properties ◽

Nano Crystalline ◽

Deformation Textures ◽

The Cross

The present study focuses on the microstructural and bioactive properties evolution in selective laser melting (SLM) β titanium alloys. We have applied cross-scan strategy for improving mechanical properties and lower elastic modulus of SLMed Ti–20Mg–5Ta alloys which has been shown to be altering the microstructure and refining the grain size. The cross-scan strategy can refine the microstructure and induce various deformation textures in contrast to the conventional scan strategy. The microstructures of Ti–20Mg–5Ta alloys indicate that the cross-scan strategy will yield the best mechanical properties and lower elastic modulus. The corrosion behavior of the Ti–20Mg–5Ta alloys was studied during immersion in an acellular simulated body fluid (SBF) at 37±0.50 °C for 28 days. Both the mechanical and bioactive properties showed that the novel Ti–20Mg–5Ta alloys should be ideal for bone implants.

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Mechanical property of octahedron Ti6Al4V fabricated by selective laser melting

REVIEWS ON ADVANCED MATERIALS SCIENCE ◽

10.1515/rams-2021-0080 ◽

2021 ◽

Vol 60 (1) ◽

pp. 894-911

Author(s):

Yun Zhai ◽

Sibo He ◽

Lei Lei ◽

Tianmin Guan

Keyword(s):

Mechanical Property ◽

Elastic Modulus ◽

Selective Laser Melting ◽

Mechanical Performance ◽

Lattice Structure ◽

Stress Shielding ◽

Human Bone ◽

Shielding Effect ◽

Basic Unit ◽

Laser Melting

Abstract The stress shielding effect is a critical issue for implanted prosthesis due to the difference in elastic modulus between the implanted material and the human bone. The adjustment of the elastic modulus of implants by modification of the lattice structure is the key to the research in the field of implanted prosthesis. Our work focuses on the basic unit structure of octahedron Ti6Al4V. The equivalent elastic modulus and equivalent density of porous structure are optimized according to the mechanical properties of human bone tissue by adjusting the edge diameter and side length of octahedral lattice. Macroscopic long-range ordered arrangement of lattice structures is fabricated by selective laser melting (SLM) technology. Finite element simulation is performed to calculate the mechanical property of octahedron Ti6Al4V. Scanning electronic microscopy is applied to observe the microstructure of octahedron alloy and its cross section morphology of fracture. Standard compression test is performed for the stress–strain behavior of the specimen. Our results show that the octahedral lattice with the edge diameter of 0.4 mm and unit cell length of 1.5 mm has the best mechanical property which is close to the human bone. The value of equivalent elastic modulus increases with the increase in the edge diameter. The SLM technology proves to be an effective processing way for the fabrication of complex microstructures with porosity. In addition, the specimen exhibits isotropic mechanical performance and homogeneity which significantly meet the requirement of implanted prosthetic medical environment.

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Mechanical Properties and Metal-Ceramic Bond Strength of Co-Cr Alloy Manufactured by Selective Laser Melting

Materials ◽

10.3390/ma13245745 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5745

Author(s):

Joon-Ki Hong ◽

Seong-Kyun Kim ◽

Seong-Joo Heo ◽

Jai-Young Koak

Keyword(s):

Mechanical Properties ◽

Elastic Modulus ◽

Flexural Strength ◽

Yield Strength ◽

Bond Strength ◽

Selective Laser Melting ◽

Laser Melting ◽

Three Point Bending ◽

Ceramic Bond ◽

Metal Ceramic

Cobalt–chromium (Co-Cr) metal is one of the widely used biomaterials in the fabrication of dental prosthesis. The purpose of this study was to investigate whether there are differences in the properties of metals and bond strength with ceramics depending on the manufacturing methods of Co-Cr alloy. Co-Cr alloy specimens were prepared in three different ways: casting, milling, and selective laser melting (SLM). The mechanical properties (elastic modulus, yield strength, and flexural strength) of the alloys were investigated by flexure method in three-point bending mode, and microstructures of the specimens were analyzed. After application of the veneering ceramic through the three-point bending test, bond strength of the Metal-Ceramic was investigated. The cracked surfaces were observed by means of energy dispersive X-ray (EDX) spectroscopy and scanning electron microscopy (SEM) with backscattered electron (BSE) images. In mechanical properties, the elastic modulus was highest for the casting group, and the yield strength and flexural strength were lowest for the milling group. The SLM group showed finer homogeneous crystalline-microstructure, and a layered structure was observed at the fractured surface. After the ceramic bond strength test, all groups showed a mixed failure pattern. The casting group showed the highest bond strengths, whereas there was no significant difference between the other two groups. However, all groups have met the standard of bond strength according to international standards organization (ISO) with the appropriate passing rate. The results of this study indicate that the SLM manufacturing method may have the potential to replace traditional techniques for fabricating dental prosthesis.

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