Department of Mechanical Engineering, Indian Institute of Technology Delhi, New Delhi 110016, India.
Department of Mechanical Engineering, Indian Institute of Technology Delhi, New Delhi 110016, India.
Mater Sci Eng C Mater Biol Appl. 2019 Oct;103:109776. doi: 10.1016/j.msec.2019.109776. Epub 2019 May 22.
Porous iron (Fe) has shown promising capabilities to be used as biodegradable material. However, to achieve the desired rate of degradation in porous Fe, there exists a need to develop a model explaining the effect of variation in morphology of the porous structure on the corrosion rate. Hence, in the present study, an empirical model for the prediction of the corrosion rate of porous Fe scaffold samples possessing different levels of porosity and pore morphology has been developed. To develop the model, Fe scaffold samples having random porous microporous structure and designed topologically ordered porous structures were fabricated using 3D printing and pressureless microwave sintering. Potentiodynamic polarization tests were performed to assess the corrosion properties of fabricated porous Fe scaffold samples in simulated body fluid solution at 37 °C. It was found that with an increase in random microporosity and the reduction in the size of the designed macropores, an increase in corrosion rate was obtained. Mathematical relationships between governing factors affecting corrosion rate (i.e. corrosion current and exposed surface area) and porosity were deduced. The developed model was validated with the experimental results and good agreement of predicted values with the experimental values was obtained with a maximum error of 6.97%.
多孔铁 (Fe) 已显示出作为可生物降解材料的应用潜力。然而，为了使多孔 Fe 达到所需的降解速率，需要开发一种模型来解释多孔结构形态变化对腐蚀速率的影响。因此，本研究开发了一种预测具有不同孔隙率和孔形态的多孔 Fe 支架样品腐蚀速率的经验模型。为了开发该模型，使用 3D 打印和无压微波烧结技术制备了具有随机多孔微孔结构和设计拓扑有序多孔结构的 Fe 支架样品。在 37°C 的模拟体液溶液中进行了动电位极化测试，以评估所制备的多孔 Fe 支架样品的腐蚀性能。结果发现，随着随机微孔率的增加和设计大孔尺寸的减小，腐蚀速率增加。推导出了影响腐蚀速率（即腐蚀电流和暴露表面积）的控制因素与孔隙率之间的数学关系。用实验结果验证了所开发的模型，预测值与实验值吻合良好，最大误差为 6.97%。
