Hybrid Dry Cutting - Finish Burnishing of Novel Biodegradable Magnesium-Calcium Implants for Superior Corrosion Performance

该奖项的研究目的是验证一个假设，即优越的表面完整性能够显著提高新型可生物降解矫形镁钙植入物的耐腐蚀性。研究方法是采用一种新型的干式切削-精加工混合抛光工艺来调节镁钙植入体的表面完整性。具体方法包括：(1)通过钙合金化和动态力学行为和微观结构表征制造可生物降解，生物相容性和轻质镁钙合金；(2)通过新型混合干切-精加工工艺与声发射过程监测创造所需的植入物表面完整性；(3)开发微尺度有限元分析模型，以提供对工艺力学和表面完整性的基本理解；(4)表征过程诱导的表面完整性及其对模拟体液中生物降解性能的影响。研究结果将通过解决与商业永久性金属植入物相关的应力屏蔽和手术干预等紧迫问题，推动生物可降解骨科植入物的发展。它将为骨科植入物的工艺参数，表面完整性和生物降解性能之间的基本关系提供见解。对社会的好处包括改善受影响个人的生活质量和减轻经济负担。生物可降解镁钙植入物的社会经济效益也将有助于提高蓬勃发展的医疗器械制造业的竞争力。

The research objective of this award is to test the hypothesis that superior surface integrity enables a significant increase of corrosion resistance of novel biodegradable orthopedic magnesium-calcium implants. The research approach is to adjust surface integrity of magnesium-calcium implants by a new hybrid dry cutting-finish burnishing process. The specific methodology includes: (1) fabrication of biodegradable, biocompatible, and lightweight magnesium calcium alloys via calcium alloying and characterization of dynamic mechanical behaviors and microstructures, (2) creation of desired surface integrity of implants through the novel hybrid dry cutting-finish burnishing process with acoustic emission process monitoring, (3) development of a microscale finite element analysis model to provide a fundamental understanding on the process mechanics and surface integrity, and (4) characterization of process-induced surface integrity and its effect on biodegradation performance in simulated body fluids.The research results will enable progress in biodegradable orthopedic implants via solving the pressing issues of stress shielding and surgical interventions associated with commercial permanent metallic implants. It will provide an insight into the basic relationships between process parameters, surface integrity, and biodegradation performance of orthopedic implants. The benefits to society include the improved life quality and reduced financial burden of the affected individuals. The socioeconomic benefits of biodegradable magnesium-calcium implants will also help boost the competitiveness of the booming medical device manufacturing industry.