应力作用下医用镁合金及其器械的腐蚀降解行为与调控机制研究

项目名称： 应力作用下医用镁合金及其器械的腐蚀降解行为与调控机制研究

项目编号： No.51271117

项目类型： 面上项目

立项/批准年度： 2013

项目学科： 一般工业技术

项目作者： 张小农

作者单位： 上海交通大学

项目金额： 80万元

中文摘要： 调控医用镁的腐蚀降解速率和力学衰减达到临床要求是其实用化的关键问题，但目前针对医用镁的腐蚀降解研究还很少涉及到应力作用下的情况，这与医用镁实际使用中存在的复杂应力条件不相符合。由于镁合金是应力腐蚀敏感的材料，尤其在含有Cl-离子环境中，所以，未考虑应力作用下的腐蚀研究对人体这种富含Cl-离子的环境来说是很不充分的，结果科学性也值得怀疑。因此，系统开展应力作用下医用镁合金的腐蚀降解行为及其调控机制的研究就显得非常必要。本课题拟采用镁锌合金为研究组，研究不同应力作用下医用镁的体外降解速率和断裂模式，建立起应力与模拟体液中镁的腐蚀降解的关联数据曲线，优选出应力腐蚀敏感性最低的镁锌合金成分和显微结构，并确定其临界应力大小。对丝材和薄板类镁合金典型器械进行应力数值模拟计算，建立植入物应力分布图。进行镁合金植入物的动物体内植入实验，研究体内应力环境下的力学衰减和断裂模式，为相关器械设计提供理论依据。

中文关键词： 镁；应力；腐蚀；降解；断裂

英文摘要： Applications of magnesium alloys as biomedical implants are crucially dependent on the understanding and controling of the unexpected overfast biodegradation as well as loss of mechanical integrity. Although it's so important to draw attention, few research has been studied on the biodegradation behaviors of magnesium alloys under the action of stress. As a fact, the biodegradable magnesium implants will be surrounded by the complex stress distribution in the clinical appliations. It is well known that the industrial magnesium alloys are highly susceptible to stress corrosion cracking (SCC) especially in the environments containg Cl-. So it is insufficient to study the biodegradation behaviors of magnesium in biological system, which is also full of Cl- ions, without considering the stress condition. Therefore, it is nessesary to fully study and establish the relationship between stress and biodegradation behavior of magnesium. This project proposes to investigate the degradation rate and cracking behavior changes under different stress effects, using the MgZn alloy as the main research group. It foucus on building connections between the stress and the in vitro biodegradation of Mg by getting mechanical test results, e.g. critical stress, to select the appropriate alloy composition and better microstucture. Mea

英文关键词： Magnesium；stress；corrosion；biodegradation；fracture