CAREER: Fundamental Problems in Dynamic Fracture Mechanics

这项研究的目的是深入了解均质材料和双材料系统在高剪切载荷作用下动态断裂的基本现象。剪切主导裂纹沿界面扩展的最新实验证据表明，超音速裂纹速度和裂纹面接触的发展。此外，理论证据预测，即使在均质材料中，在高剪切载荷下，如果均质材料表现出内聚型破坏响应，超音速也是如此。在这里，将进行实验和数值分析，以仔细检查接触区的物理细节和双材料界面和均匀材料系统中的极限裂纹速度。将特别强调接触过程中的裂纹面摩擦和随后的加热问题。该提案的教育部分描述了一项改进现有课程和增强的本科实验室的教学实践的计划，包括生动的课堂演示以及反直觉动力系统的实物演示。

The objective of the proposed research is the thorough understanding of fundamental phenomena in dynamic fracture of homogeneous and bimaterial systems subjected to high shearing loads. Recent experimental evidence during shear dominated crack propagation along interfaces, has shown the development of supersonic crack speeds and crack face contact. In addition, theoretical evidence predicts supersonic speeds even in homogeneous materials, under high shear loading, if the homogeneous material exhibits a cohesive type failure response. Here, experimental and numerical analysis will be conducted to scrutinize the physical details of the contact zone and of limiting crack speedsin bimaterial interface and homogeneous material systems. Special emphasis will be placed on the issue of crack face friction and subsequent heating during contact. The educational part of this proposal describes a plan for improvement of teaching practices in current courses and enhanced undergraduate laboratories, including animated classroom presentations as well as physical demonstrations of counter-intuitive dynamical systems.