US-Italy Cooperative Research: Linking Deformation Length Scales in Transforming Materials

0437345Sehitoglu这一为期三年的奖项支持美国和意大利在“变形材料中的连接变形长度尺度”方面的合作研究，参与研究的有伊利诺伊香槟大学的Husedin Sehitoglu和米兰理工大学(MPU)的Piermaria Davoli。滑移的存在是材料转化中的一个主要问题。它限制了相变应变和相变可逆性。这项拟议的研究将试验和开发力学模型，以了解相变应力如何随温度和循环加载而变化。此外，拟议的合作将模拟对总体可恢复菌株的去孪生贡献。最后，PI将侧重于剪切加载，以了解应力状态对断裂和转变行为的作用。米兰理工大学拥有在多轴应力状态下进行实验的世界级设备。这样的设施运营成本很高，而且需要一流的实验者。因此，他们的能力在世界上只有少数几个机构能与之匹敌。MPU的这些能力与PI的能力有很强的协同作用，PI一直参与循环变形和疲劳，专注于转化材料。这项拟议的研究有望获得有关在执行器、传感器和其他工程应用中使用半脆性材料的信息。这些材料很可能用于太空或生物应用。

0437345SehitogluThis three-year award supports US-Italy cooperative research on "Linking Deformation Length Scales in Transforming Materials," involving Huseyin Sehitoglu of the University of Illinois-Champaign and Piermaria Davoli of the Milan Polytechnic University (MPU). The presence of slip is a major issue in transforming materials. It limits transformation strains and transformation reversibility. The proposed research will experiment and develop mechanics models to understand how the transformation stress changes with temperature and cyclic loading. In addition, the proposed collaboration will model the detwinning contribution to overall recoverable strains. Finally, the PIs will focus on shear loading to understand the role of stress states on fracture and transformation behavior. The Milan Polytechnic University has world-class facilities in conducting experiments in multiaxial stress states. Such facilities are expensive to operate, and require first-rate experimentalists. Consequently their capabilities are matched in only a few institutions in the world. There is strong synergy between these capabilities at MPU and that of the PI, who has been involved in cyclic deformation and fatigue focusing on transforming materials. The proposed research is expected to result in information regarding the use of semi-brittle materials in actuators, in sensors, and other engineering applications. It is likely that these materials could be used in space or in bioapplications.