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

0437345Sehitoglu这个为期三年的奖项支持美国和意大利合作研究“连接变形材料中的变形长度尺度”，涉及伊利诺伊大学香槟分校的Huseyin Sehitoglu和米兰理工大学的Piermaria Davoli。 滑移的存在是材料转化中的一个主要问题。 它限制了转化应变和转化可逆性。 拟议的研究将实验和开发力学模型，以了解相变应力如何随温度和循环载荷而变化。 此外，拟议的合作将模拟解孪对整体可恢复菌株的贡献。 最后，PI将关注剪切载荷，以了解应力状态对断裂和转变行为的作用。米兰理工大学拥有世界一流的多轴应力状态实验设施。 这种设备的操作费用很高，而且需要一流的实验人员。 因此，世界上只有少数几个机构的能力与它们相当。 MPU的这些能力与PI的能力之间有很强的协同作用，PI参与了循环变形和疲劳，重点是转换材料。 拟议中的研究预计将导致在执行器，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.