论文部分内容阅读
本文扼要介绍了X射线微光束技术的原理和用途,以及利用这种技术测定了氢致恒载荷下的工业纯铁裂纹尖端处阴极充氢前后的点阵畸变,亚晶取向差及晶界过剩位错密度的变化。结果表明,充氢后在具有应力梯度的裂纹尖端的弹塑区增大,晶界过剩位错密度增加,越靠近裂纹尖端,晶界过剩位错密度变化越大。说明氢致塑能力随应力梯度的增加而增大,另外在裂纹尖端处点阵畸变不是变化最大点,而最大值在离开裂纹尖端的一定距离处。
This paper briefly introduced the principle and application of X-ray micro-beam technology, and used this technique to measure the lattice distortion, sub-crystal orientation difference and excessive grain boundary before and after hydrogen charging of the industrial pure iron under the hydrogen-induced constant load Dislocation density changes. The results show that after hydrogen charging, the elastic-plastic zone increases and the excess grain boundary dislocation density increases at the crack tip with stress gradient. The closer to the crack tip, the greater the change of grain boundary over-dislocation density. It shows that the hydrogen plasticity increases with the increase of the stress gradient. In addition, the lattice distortion is not the maximum point at the crack tip, and the maximum value is at a distance from the crack tip.