Investigation of Solid State Reaction by Means of Direct Observation of Atomistic Structural Changes

直接观察缺陷反应的最好方法是利用高压电子显微镜中的高能电子辐照：(A)系统地研究了溶质添加对缺陷结构演变的影响，(B)通过叠加电子辐照建立了一种识别中子辐照材料中小点缺陷团簇性质的方法，并将其应用于代表性材料，(C)阐明了位错周围应变场对级联缺陷的影响，(D)成功地在电子辐照诱导位错环的生长过程中检测到了点缺陷反应过程的随机波动，(E)用新设计的间歇辐照技术测量了短松弛现象。关于高能中子辐照引起的缺陷微观结构：(F)电子显微镜下不可见的小缺陷团簇在铁中的作用被阐明了…系统地研究了溶质元素对缺陷组织演变的影响；(I)研究了中子辐照过程中缺陷随温度变化的机理。无位错晶体金属的塑性变形是本研究项目中最重要和最新的课题：(J)通过在电子显微镜上直接观察变形过程，证实了位错操作的缺失；(K)通过动态观察点缺陷簇的出现和消失，得出结论：点缺陷是作为分散的点缺陷引入的，而不是点缺陷簇；(L)通过塑性变形析出物的变形成功地测量了局部应变，(M)用含有各种二次缺陷的样品研究了变形模式，(N)所有这些实验结果都提出了在极高的内应力条件下，以滑移元素取代位错的新的形变机制。对高速变形的研究表明，应变速率为10^7/S，当应变速率超过10^5/S时，(O)缺陷组织发生剧烈变化。

The most superior method of direct observation of defect reactions is to utilize high energy electron irradiation in a high-voltage electron microscope : (a) A systematic investigation has been performed on the effect of solute addition to defect structure evolution, (b) A method of the identification of the nature of small point defect clusters in neutron irradiated materials was established by superimposing electron irradiation and applied to representative materials, (c) Effect of strain field around dislocation on cascade defects was elucidated, (d) Detection of stochastic fluctuation of point defect reaction processes was successfully made during the growth of electron irradiation-induced dislocation loops, (e) Measurement of short relaxation phenomena was made by newly designed intermittent irradiation technique. As for the defect microstructures induced by high energy neutron irradiation : (f) The role of electron microscopically invisible small defect clusters in iron was eluci … More dated, (g) Relation between the destination of cascade collision induced point defects and the microstructure evolution was studied, (h) Effect of solute elements to the defect microstructure evolution was systematically investigated, (i) The mechanism of defect reaction during neutron irradiation with temperature variation was also studied. Plastic deformation of crystalline metals without dislocation was the most important and new subject in this research project : (j) Absence of the operation of dislocations was confirmed by direct observation of the progress of deformation in an electron microscope, (k) From the dynamic observation of the appearance and disappearance of point defect clusters, point defects are concluded to be introduced as dispersed point defects, but not as point defect clusters, (l) Local strain was successfully measured by the deformation of plastically deformable precipitates, (m) Deformation mode was examined by using samples containing various kinds of secondary defects, (n) all of these experimental results lead to the proposal of a new mechanism of deformation with glide elements which replace dislocations, under the condition of extremely high internal stress. Investigation of high-speed deformation achieved the strain rate of 10^7/s, and (o) Defect structures were found to change drastically by the deformation with strain rate over 10^5/s. Less