Vacancies and carbon impurities inα- iron: Electron irradiation
Vacancies and carbon impurities inα- iron: Electron irradiation
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DOI：
10.1103/physrevb.25.762
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发表时间：
1982-01
影响因子：
3.7
通讯作者：
A. Vehanen;P. Hautojärvi;J. Johansson;J. Yli-kauppila;P. Moser
中科院分区：
文献类型：
--
作者：
A. Vehanen;P. Hautojärvi;J. Johansson;J. Yli-kauppila;P. Moser
本文报道了电子辐照高纯α-铁和掺杂可控量碳杂质的铁的正电子寿命测量结果。我们发现，在纯铁单空位是移动的在第三阶段约220 K造成空缺成小的三维团聚体集群。这些团簇在500至600 K之间退火。在掺碳铁中，竞争机制是在200 K下形成高度不对称的碳空位对。这些对在490 K左右解离，导致晶格中的自由空位的另一次释放。在早期的调查空缺性质的争议方面进行了讨论。
Positron-lifetime measurements are reported on electron-irradiated high-purity α-iron and on iron doped with controlled amounts of carbon impurities. We show that in pure iron monovacancies are mobile at stage III around 220 K causing vacancy clustering into small three-dimensional agglomerates. These clusters anneal out between 500 and 600 K. In carbon-doped iron a competing mechanism is the formation of a highly asymmetric carbon-vacancy pair at 200 K. These pairs dissociate around 490 K, resulting in another release of free vacancies in the lattice. Controversial aspects on vacancy properties in earlier investigations are discussed.