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材料结构,第3部分:液晶、缺陷和扩散

Structure of Materials, Part 3: Liquid Crystals, Defects, and Diffusion
课程网址: https://openlearninglibrary.mit.edu/courses/course-v1:MITx+3.012S...  
主讲教师: Silvija Gradečak
开课单位: 麻省理工学院
开课时间: 2019-01-01
课程语种: 英语
中文简介:
结构在很大程度上决定了一种材料:它的特性、潜在应用以及在这些应用中的性能。本课程是麻省理工学院材料科学与工程系的三部分系列课程的最后一部分,该系列课程探索了当前工程应用中各种材料的结构。综上所述,这三门课程提供了与麻省理工学院二年级材料结构课程相似的内容。 第3部分首先探讨准晶体、塑料晶体和液晶。接下来,我们将了解材料的性能是如何受到结构缺陷的影响和修改的。我们将展示在有限温度下所有晶体中都存在点缺陷,以及它们的存在如何控制材料中的扩散。接下来,我们将探索材料中的位错。我们将介绍用于描述位错的描述符,我们将了解位错运动,并考虑位错如何显著地影响材料的强度。最后,我们将探讨如何利用缺陷来强化材料,并将了解其他结构缺陷的特性,如层错和晶界。
课程简介: Structure determines so much about a material: its properties, its potential applications, and its performance within those applications. This course is the finale in a three-part series from MIT’s Department of Materials Science and Engineering that explores the structure of a wide variety of materials with current-day engineering applications. Taken together, these three courses provide similar content to MIT’s sophomore-level materials structure curriculum. Part 3 begins with an exploration of quasi-, plastic, and liquid crystals. Next, we will learn how properties of materials are influenced and can be modified by structural defects. We will show that point defects are present in all crystals at finite temperatures and how their presence governs diffusion in materials. Next, we will explore dislocations in materials. We will introduce the descriptors that are used to describe dislocations, we will learn about dislocation motion and consider how dislocations dramatically affect the strength of materials. Finally, we will explore how defects can be used to strengthen materials, and we will learn about the properties of other structural defects such as stacking faults and grain boundaries.
关 键 词: 晶体; 塑料晶体; 液晶; 结构缺陷
课程来源: 麻省理工学院公开课
数据采集: 2021-10-12:nkq
最后编审: 2021-10-12:nkq
阅读次数: 72