Huang Zhihua, Allison John E, Misra Amit
Department of Materials Science and Engineering, University of Michigan, Ann Arbor, United States.
Sci Rep. 2018 Feb 23;8(1):3570. doi: 10.1038/s41598-018-20629-1.
The unit processes of precipitate-dislocation interaction in dilute Mg-Nd alloys are elucidated through in situ indentation experiments in TEM. Results suggest that pinned dislocations can glide along the broad facets of extended β precipitates, a common strengthening phase in Mg- rare earth (RE) alloys. A dislocation-theory based analysis suggests that the shape, spacing and orientation (with respect to the glide plane) of β precipitates may favor glide of pinned dislocations along interfaces as opposed to the classical mechanism of bowing and looping around the precipitate.
通过透射电子显微镜（TEM）原位压痕实验阐明了稀Mg-Nd合金中沉淀-位错相互作用的单元过程。结果表明，被钉扎的位错可以沿着扩展β相沉淀的宽平面滑动，β相沉淀是Mg-稀土（RE）合金中常见的强化相。基于位错理论的分析表明，β相沉淀的形状、间距和取向（相对于滑移面）可能有利于被钉扎的位错沿界面滑动，这与位错在沉淀周围弯曲和形成环的经典机制相反。
