同济大学：《结构力学》课程教学资源（教案讲稿，打印版）07 Elastic Deflections（弹性变形）of Trusses and Frameworks

第一节 点缺陷 POINT DEFECTS 点缺陷的形成 点缺陷的浓度 点缺陷的运动 点缺陷与材料行为 第二节 位错的基本概念 PRIMARY CONCEPT OF DISLOCATION 位错学说的产生 位错的基本类型和特征 位错的运动 第三节 位错的弹性性质 THE ELASTIC NATURE OF 位错的应力场 位错的应变能 作用在位错上的力 位错的线张力 位错与点缺陷的交互作用 位错间的交互作用力 第四节 位错的增殖 位错的密度 位错的增殖 第五节 实际晶体结构中的位错 THE DISLOCATION IN ACTUAL CRYSTAL STRUCTURE 实际晶体 结构中的 伯氏矢量 堆垛层错 不全位错 位错反应 面心立方 第五节 表面与界面 外表面 晶界与亚 晶界 孪晶界 相界

4-1-1 材料的力学状态 mechanical states of matrials 4-1-2 应力和应变 stress-strain 4-1-3和4-1-4 材料的形变 Deformation of Materials 4－1－3 弹性形变 Elastic deformation 4-1-4永久变形(permanent deformation)

Interference Constraints Capacity and CAC Power Control Scheduling Elastic Transfers Summary

1. Standards and Calibration 2. Basic methods of Force Measurement 3. Characteristics of Elastic Force Transducers 4. Resolution of Vector Forces and Moments into Rectangular Components 5. Torque Measurement on Rotating Shafts 6. Shaft Power Measurement (Dynamometers) 7. Vibrating-Wire Force Transducers

TEM in situ tensile tests of 310 stainless steel show that a dislocation free zone (DFZ) forms if the displacement keeps constant after dislocations are emitted from a crack tip. The elastic DFZ is gradually thinned and the stress in the DFZ will reach the cohesive strength, resulting in nucleation of nanocracks in it and their bluntness into voids. If continuously tensioning, the inhomogeneously thinning ahead of the crack tip, initiat-ing and connecting of microcracks or microvoids will be observed rather than a DFZ, nanocracks' initiation and bluntness into voids. The inverse pile-up ahead of a loaded crack tip can move back to the crack tip when unloading

西安建筑科技大学：《材料物理性能》课程教学资源（授课教案）第一章 材料的弹性变形 Elastic deformation of materials

1 完全弹性碰撞(complete elastic collision) 系统内动量和机械能均守恒 2 非弹性碰撞(Inelastic collision ) 系统内动量守恒，机械能不守恒 3 完全非弹性碰撞(Complete inelastic collision ) 系统内动量守恒，机械能不守恒

Elastic Demand Shows Large￾Quantity Response to Price Change

一、碰撞(collision) 碰撞两物体互相接触时间极短而互作用力较大的相 互作用∵F<