The application of the bifurcation theory to the microstructure change and its stability.

分岔理论在微观结构变化及其稳定性中的应用

基本信息

批准号：
02452245
负责人：
MIYAZAKI Toru
金额：
$ 4.35万
依托单位：
Nagoya Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1990
资助国家：
日本
起止时间：
1990 至 1991
项目状态：
已结题

项目摘要

Several interesting phenomena for the formation of microstructure have recently been observed when the alloys, ceramics and semiconductors are elastically constrained. Particularly, the extraordinary behavior, in the precipitate coarsening ; deceleration of particle coarsening, stopping the particle coarsening and splitting of a particle into plural small particles are typical examples. These phenomena have theoretically supported by "bifurcation diagram", proposed by us. In the practical point of view, this phenomena imply an existence of non-overaging materials even if heated at high temperature for atom to diffuse. The purpose of the present work is to get a more wide range of experimental examinations and also to give more accurate theoretical back ground.The experimental results obtained for this academic year are written below.(1) Hitherto the splitting of particle was recognized in Ni-base alloys such as Ni-Al, Ni-Si and so on. However, the splitting has first been observed in I … More ron base Fe-Al-Co ternary alloys. This examination fact clearly shows that the splitting of particles is not special but common in the elastically constrained system.(2) In the Fe-Al-Ge system which has a small eigenstrain the precipitates increase their sizes L with aging time t in accordance with LSW theory, that is L=k ・t^<1/3>. In the Fe-Al-V system having a large eigenstrain, however, the uniformalization of particle size and the deceleration of particle coarsening were experimentally recognized. Inevitability of such the characteristic coarsening is theoretically discussed on the basis of the bifurcation diagram.(3) New parameters showing the 3-dimensional distribution of particles are introduced to classify the microstructures(4) In the conventional bifurcation disgrain the microstructure consisting two particles vas adopted as the most simple case of the many body microstructure. In this research, the many body microstructure is taken into the calculation of bifurcation diagram so as to analyze more accurate behavior of the particle coarsening. Less

当合金，陶瓷和半导体受到弹性限制时，最近观察到了微观结构形成的几种有趣现象。特别是在珍贵的浓缩中的非凡行为；粒子变硬的减速，阻止粒子粗化和将粒子分裂为复数小颗粒的碎片是典型的例子。这些现象通过我们提出的“分叉图”具有理论上的支持。从实际的角度来看，即使在高温下加热原子以扩散，这种现象也意味着存在非掩盖材料。本工作的目的是获得更广泛的实验检查，并提供更准确的理论背景。（1）迄今为止，在Ni-Base合金中识别了粒子的分裂，例如Ni-Al，Ni-Si等。但是，首先在I…更多的Ron Base Fe-Al-Co三元合金中观察到了分裂。该检查事实清楚地表明，颗粒的分裂不是特殊的，但在弹性约束的系统中很常见。（2）在Fe-Al-GE系统中，具有较小的特征性的Fe-Al-GE系统中，降水量会随着LSW理论的衰老时间t增加了尺寸L，即L = K t^<1/3>。然而，在具有较大本征膜的Fe-Al-V系统中，粒径的均匀化和颗粒变质的减速是在实验中识别的。理论上讨论了这种特征变质的必然性。（3）引入了介绍颗粒的3维分布的新参数，以对传统的分支中的微观结构（4）分类，以使传统的分支误解了将两个颗粒vas的微观结构误解，这些微观结构将两个粒子vas vas组成最简单的案例。在这项研究中，将许多身体微观结构用于分叉图的计算，以分析颗粒更粗化的更准确的行为。较少的