Plasticity and Fracture

通过这项研究，我们寻求对科学和工程感兴趣的材料的力学行为的基本理解。这项工作的目的是完整地描述材料对变形和断裂的抵抗力。这一领域的研究必然是跨学科的，其活动跨越了从基础理论，通过实验和观察，到详细的建模和模拟的范围。理论研究为讨论现象和假设材料变形和断裂的物理机制提供了框架，并提供了应该测量的物理量的定义。另一方面，实验研究提供了识别复杂物质现象学的手段，并提供了理论工作中确定的物理量的定量信息。为了完成这个循环，分析建模和计算机模拟提供了检验理论概念有效性的手段，并得出了不能直接从实验数据推断出的关于材料行为的结论。如果要做出重大的基础性贡献，就必须将这些要素中的每一个都纳入一个全面的研究计划。本研究的主要主题包括：(1)速率和温度对非弹性变形机制和断裂行为的影响；(2)建立微观微观结构机制与宏观行为之间的定量联系；(3)探索界面在变形断裂机制中的作用；(4)研究不稳定和局部变形，特别是作为破坏的直接前兆。

Through this research we seek a fundamental understanding of the mechanical behavior of materials of scientific and engineering interest. The objective underlying the work is a complete characterization of the resistance of material to deformation and fracture. Research in this area is necessarily interdisciplinary with activities that span the spectrum from basic theory, through experiment and observation, to detailed modelling and simulation. Theoretical studies provide the framework for discussing phenomena and for postulating physical mechanisms of materials deformation and fracture as well as provide definitions of physical quantities that should be measured. Experimental studies, on the other hand, provide the means of identifying complex material phenomenology and provide quantitative information on the physical quantities identified in theoretical work. To complete the loop, analytical modelling and computer simulation provide the means to examine the validity of theoretical concepts and to draw conclusions about the behavior of materials that could not be inferred directly from experimental data. It is essential that each of these ingredients be included in a comprehensive research program if significant fundamental contributions are to be made. Major themes of this research include: (1) the effects of rate and temperature on inelastic deformation mechanisms and fracture behavior; (2) the establishment of quantitative links between microscopic microstructural mechanisms and macroscopic behavior; (3) exploration of the role of interfaces on the mechanisms of deformation and fracture; and (4) the study of unstable and localized deformation, especially as a direct precursor to failure.