Transmission electron microscopy observations on the microstructure of naturally aged Al–Mg–Si alloy AA6022 processed with an electric field
Transmission electron microscopy observations on the microstructure of naturally aged Al–Mg–Si alloy AA6022 processed with an electric field
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DOI：
10.1007/s10853-006-0840-y
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发表时间：
2006-09
影响因子：
4.5
通讯作者：
H. Conrad;S. Ramachandran;K. Jung;J. Narayan
中科院分区：
文献类型：
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作者：
H. Conrad;S. Ramachandran;K. Jung;J. Narayan
采用透射电子显微镜和选区电子衍射测定了AA 6022在固溶热处理过程中和随后的短期初始自然老化过程中施加的电场对自然老化长时间（2-3年）后析出物性质的影响。沉淀物呈球形，直径2 ~ 40 nm，平均7.9nm。它们的平均尺寸大于未经磁场处理的试样（4.9 nm），且其尺寸分布中dp> 1.3 nm的沉淀物数量较多。此外，它们的晶体结构不同于未经磁场处理的样品。电场处理使析出相尺寸增大，晶体结构发生变化，从而使析出相与位错之间的相互作用力增大，从而使屈服应力增大。
The influence of an electric field applied during the solution heat treatment and during a short subsequent initial natural aging of AA6022 on the nature of the precipitates which occurred after natural aging for a long time (2–3 years) was determined employing transmission electron microscopy and selected area electron diffraction. The precipitates were spherical in shape ranging from 2 nm to 40 nm in diameterdpwith an average of 7.9 nm. Their average size was larger than that (4.9 nm) in a specimen processed without field and their size distribution had a greater number of precipitates withdp>∼3 nm. Moreover, their crystal structure differed from that in specimens processed without a field. The increase in yield stress which occurred with the electric field treatments is attributed to an increase in the interaction force between the precipitates and dislocations, which resulted from the larger size and different crystal structure of the precipitates by the field.