论文标题
通过微压和并发的声发射实验研究了辐照诱导的应变定位和应变爆发抑制
Irradiation-induced strain localization and strain burst suppression investigated by microcompression and concurrent acoustic emission experiments
论文作者
论文摘要
微观样本的塑性变形的特征是由脱位雪崩引起的较大的间歇性应变爆发。在这里，我们研究了单个滑动单晶体可塑性期间如何影响离子辐射对此现象的影响。为此，在SEM中进行了以基底滑动为导向的Zn微柱的原位压缩。独特的实验设置还允许在变形过程中同时记录样品中从样品中发出的声学信号（AE）。结果表明，辐照引入了基础位错环的均匀分布，从而导致样品硬化以及由于较大菌株的脱位通道而引起的应变软化。由于通道，发现使用的变形方案应变爆发尺寸减小。同时记录的AE事件与应变爆发相关，其分析提供了集体错位动力学细节的其他信息。发现AE事件的发生率在照射后显着降低，但是，其他统计特性没有改变。这归因于一种新型塑料事件的外观，该事件由AE传感器无法检测到的短距离错位相互作用主导。
Plastic deformation of microsamples is characterised by large intermittent strain bursts caused by dislocation avalanches. Here we investigate how ion irradiation affects this phenomenon during single slip single crystal plasticity. To this end, in situ compression of Zn micropillars oriented for basal slip was carried out in a SEM. The unique experimental setup also allowed the concurrent recording of the acoustic emission (AE) signals emitted from the sample during deformation. It was shown that irradiation introduced a homogeneous distribution of basal dislocation loops that lead to hardening of the sample as well as strain softening due to dislocation channeling at larger strains. With the used deformation protocol strain burst sizes were found to be decreased due to channeling. The concurrently recorded AE events were correlated with the strain bursts and their analysis provided additional information of the details of collective dislocation dynamics. It was found that the rate of AE events decreased significantly upon irradiation, however, other statistical properties did not change. This was attributed to the appearance of a new type of plastic events dominated by short-range dislocation-obstacle interactions that cannot be detected by AE sensors.
