Rashia Begum S, Saravana Kumar M, Vasumathi M, Umar Farooq Muhammad, Pruncu Catalin I
Department of Mechanical Engineering, College of Engineering, Anna University, Chennai, Tamil Nadu, India.
Department of Production Engineering, National Institute of Technology, Tiruchirappalli, Tamil Nadu, India.
Proc Inst Mech Eng H. 2022 Jan 11:9544119211070412. doi: 10.1177/09544119211070412.
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.
增材制造通过其在骨支架开发中的关键应用，正在彻底改变医学科学领域。在支架制造过程中，要实现良好的孔隙率以提高机械强度极具挑战性。骨支架应兼具孔隙率和承载能力。在本研究中，设计了一种新颖的结构，旨在评估灵活的孔隙率。使用特定输入参数为该新颖结构生成了CAD模型，而孔隙率则通过改变输入参数来控制。聚酰胺（PA 2200）材料被用于制造骨支架，这是一种生物相容性材料。为制造骨支架的新颖结构，使用了选择性激光烧结机（SLS）。使用万能试验机（UTM）观察压缩载荷下的位移。除此之外，还对部件进行了数值分析。通过分析得出的压缩刚度能够验证特定骨支架模型的承载能力。将实验孔隙率与理论孔隙率进行比较，结果表明与理论孔隙率相比，实验孔隙率降低了近29%至30%。通过改变几何形状，使用ANSYS进行了结构分析。使用ANSYS FLUENT进行计算流体动力学（CFD）分析，以估计血压和壁面剪应力（WSS）。从CFD分析中，观察到最大压力为1.799 Pa。尽管孔隙率小于50%，但WSS的变化不大。本研究的成果证实了所提出模型的巨大潜力，这些模型能够成功地应用于所需的骨植入应用。
