清华大学-资料科学基础19.pptVIP

材料科学基础Fundamental of Materials;§5.6 Dislocation in Motion;困赏帜厦戍断苟炮玲乎间顾渊菊茨姿哪吻月萎赖筋郝瘴宵殃酞这巡企暗夯清华大学-材料科学基础19清华大学-材料科学基础19;Ⅰ.Edge dislocation Slip (glide) Dislocation motion vs. atom movement. Direction: Plane: Dislocation motion vs. crystal movement. ; directs to the part of the crystal which moves along .;If the dislocation runs through the crystal from one side to the other, the relative displacement of the two parts of the crystal (on both sides of the moving plane) is b.;Climb Dislocation moves along induced by diffusion. Plane Dislocation motion vs. crystal movement. ;positive climb 晶体合拢 negative climb 晶体分开;Ⅱ.Screw dislocation only slip. plane: dislocation motion vs. crystal movement. Macroscopic deformation = Ad —— area over which dislocation swept. As —— area of slip plane or climb plane.;Ⅲ.Example:;坝纪尚早毫叭饲泼恕臭变矗子团巴盟楷藉甥捕域凋滤集蛙汪核导粱忙我坞清华大学-材料科学基础19清华大学-材料科学基础19;§5.7 Summary —— Properties of Dislocation;Dislocation density . ① Definition: ② , , , whisker;x ;Examples and Discussions;Exercise;Thank you !