裂纹片

当裂纹与片层界面的夹角不同时，γ相所表现的两种截然不同的断裂方式表明在TiAl合金的脆性本质中包含有位错动力学的因素。

As the angle between tensile axis and lamellar interface varies , that two kinds of different fracture modes existed in γ phase indicates that dislocation dynamics may be an important reason on embrittlement of TiAl alloys .

首先介绍了直流电位法&裂纹扩展片检测裂纹的方法和原理。

The principle and method for testing surface crack through direct current potential difference are introduced .

避免发生芯片裂纹的倒装片BGA技术概述

Research for Flip - Chip BGA Technology to Avoid Cracking

SEM观察表明，裂纹偏转、片晶桥接是主要增韧机理，片晶拔出、基体细化等亦对断裂韧性的增加作出贡献，其作用与晶须增韧的机理相似。

SEM observation shows that crack deflection and platelet bridging are the main toughing mechanisms , and platelet pull-out and reinforcement of the matrix grains also contributed to the improvement in the fracture toughness , which is similar to that of whisker toughening .

[001]籽晶生长的晶体中很少发现裂纹、聚片孪晶等宏观缺陷。

Macro defects like cracks and lamellar twins were seldom observed in the seed grown crystals .

利用裂纹扩展阻力曲线法预测了预裂纹试验片的疲劳门槛值条件，所预测的值与试验结果相当吻合。

The resistance curve measurement for crack extension is applied to predict the fatigue threshold conditions of the pre-crack specimens . The result agrees well with that of the experiment .

在TEM下原位观察了双相TiAl层状组织对裂纹扩展的影响，发现裂纹尖端的钝化以及裂纹的扩展方式与裂纹和片层界面的夹角有关。

In situ TEM technique was employed to observe the influence of lamellar structure on the crack propagation in duplex TiAl alloy . It has been found that both crack tip blunting and crack propagating have connected with the angle included between crack growth and lamellar direction .