Revealing the compressive and flow properties of novel bone scaffold structure manufactured by selective laser sintering technique

Author(s):  
S Rashia Begum ◽  
M Saravana Kumar ◽  
M Vasumathi ◽  
Muhammad Umar Farooq ◽  
Catalin I Pruncu

Additive manufacturing is revolutionizing the field of medical sciences through its key application in the development of bone scaffolds. During scaffold fabrication, achieving a good level of porosity for enhanced mechanical strength is very challenging. The bone scaffolds should hold both the porosity and load withstanding capacity. In this research, a novel structure was designed with the aim of the evaluation of flexible porosity. A CAD model was generated for the novel structure using specific input parameters, whereas the porosity was controlled by varying the input parameters. Poly Amide (PA 2200) material was used for the fabrication of bone scaffolds, which is a biocompatible material. To fabricate a novel structure for bone scaffolds, a Selective Laser Sintering machine (SLS) was used. The displacement under compression loads was observed using a Universal Testing Machine (UTM). In addition to this, numerical analysis of the components was also carried out. The compressive stiffness found through the analysis enables the verification of the load withstanding capacity of the specific bone scaffold model. The experimental porosity was compared with the theoretical porosity and showed almost 29% to 30% reductions when compared to the theoretical porosity. Structural analysis was carried out using ANSYS by changing the geometry. Computational Fluid Dynamics (CFD) analysis was carried out using ANSYS FLUENT to estimate the blood pressure and Wall Shear Stress (WSS). From the CFD analysis, maximum pressure of 1.799 Pa was observed. Though the porosity was less than 50%, there was not much variation of WSS. The achievement from this study endorses the great potential of the proposed models which can successfully be adapted for the required bone implant applications.

2014 ◽  
Vol 592-594 ◽  
pp. 836-841
Author(s):  
Kishore A. Arul ◽  
Begum S. Rashia ◽  
G. Arumaikkannu

Additive manufacturing (AM) is one the advanced process for building up a component layer by layer, with one layer of material was bonded to the previously laid layer using a 3D design data. In the field of medical science AM is very much useful in the development of Bone Scaffolds. The bone scaffold needs the good level of porosity for the cultivation of cells. In this work, an algorithm for a novel structure with the theme of flexible porosity was introduced. Scaffold models were developed using CATIA V5 for four different porosities. The novel structures made of Poly Amide (PA 2200) material were fabricated using a commercially available Selective Laser Sintering machine (SLS). The differences in scaffold theoretical and experimental porosities were investigated and the percentage of error was discussed.


2015 ◽  
Vol 22 (5) ◽  
pp. 1171-1178 ◽  
Author(s):  
Jianhua Zhou ◽  
Chengde Gao ◽  
Pei Feng ◽  
Tao Xiao ◽  
Cijun Shuai ◽  
...  

2013 ◽  
Vol 19 (5) ◽  
pp. 1345-1348
Author(s):  
Fwu-Hsing Liu ◽  
Sheng-Lih Yeh ◽  
Chil-Chyuan Kuo

2020 ◽  
Vol 1012 ◽  
pp. 278-283
Author(s):  
Henrique Schappo ◽  
Lya Piaia ◽  
Dachamir Hotza ◽  
Gean Vitor Salmoria

Human bone has a complex geometry, varying its structure and composition. Additive manufacturing processes, such as selective laser sintering (SLS), can produce bone scaffolds with a wide range of biomaterials. Through SLS a complex structure with highly interconnected porous can be fabricated from a combination of materials. Composites made from biopolymers and bioceramics have shown promising results for bone regeneration, although some properties still must be enhanced. Finding suitable processing parameters is mandatory to achieve required final properties. This review paper is focused on polymer/ceramics using SLS machines in the last 10 years.


NANO ◽  
2012 ◽  
Vol 07 (03) ◽  
pp. 1250015 ◽  
Author(s):  
CIJUN SHUAI ◽  
CHENGDE GAO ◽  
YI NIE ◽  
PENGJIAN LI ◽  
JINGYU ZHUANG ◽  
...  

Serious microcracks often occur on the surface of nanohydroxyapatite (n-HAP) artificial bone scaffolds prepared by selective laser sintering (SLS) technology. In this study, we found that appropriate preheating before sintering can reduce and attenuate the cracks. The microstructure and morphology of sintered n-HAP were tested at different preheating temperature and laser sintering speed with scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FT-IR). The experiments showed that the cracks gradually reduced and then disappeared when the preheating temperature increased from 0°C to 600°C while other parameters remain unchanged. The n-HAP particles gradually fused and grew up, while the grain size of sintered n-HAP will be attenuated with the increase of preheating temperature. As the thermal conductivity of n-HAP increases with increased preheating temperature, the temperature drops quickly, inhibiting greatly the grain growth of n-HAP. We obtained a group of optimum parameters when the sintered n-HAP still maintains nanostructure and possesses the optimal comprehensive performances, that is, laser power is 26 W, spot diameter is 4 mm, sintering speed is 200 mm/min, layer thickness is 0.4 mm, layer density is 852 kg/m3, and optimized preheating temperature is 600°C. These data illustrated that the cracks of sintered n-HAP can be eliminated at appropriate preheating temperature and sintering speed. This provided experimental optimal condition for the preparation of artificial bone scaffolds with nanohydroxyapatite ceramics.


BioResources ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. 1338-1353
Author(s):  
Jian Li ◽  
Aboubaker I. B. Idriss ◽  
Yanling Guo ◽  
Yangwei Wang ◽  
Zhiqiang Zhang ◽  
...  

Selective Laser Sintering (SLS) technology can be utilized to recycle residues from forestry and agriculture, thereby alleviating shortages of materials and reducing energy consumption by producing wood-plastic pieces for industrial application. The mechanical strength of wood-plastic SLS parts is low, which restricts the application of this technology. In this study, a novel type of sisal fiber/poly-(ether sulfone) (PES) composite was prepared using a polymer mixing method in order to improve the mechanical properties of SLS parts. Single-layer sintering method was adopted to determine the proper processing parameters. The mechanical properties of the parts with different ingredient ratios and different particle sizes of sisal fiber before and after post-processing were tested using a universal testing machine. The morphology was examined using scanning electron microscopy (SEM). Results showed that the mechanical properties of the printed parts were relatively enhanced; when the mixing ratio of composite powder was 10/90 wt/wt. In addition, the part fabricated by powder of particles size less than 0.105 mm (0.125 mm ≥ PS < 0.105mm) had the best mechanical strength. Moreover, the post-wax treatment significantly improved the strength of the parts, and the surfaces became smoother.


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