Growth behavior of hydrogen micropores in aluminum alloys during high-temperature exposure
Growth behavior of hydrogen micropores in aluminum alloys during high-temperature exposure
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DOI：
10.1016/j.actamat.2009.01.026
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发表时间：
2009-04
期刊：
影响因子：
9.4
通讯作者：
H. Toda;Tatsumasa Hidaka;M. Kobayashi;K. Uesugi;A. Takeuchi;K. Horikawa
中科院分区：
文献类型：
--
作者：
H. Toda;Tatsumasa Hidaka;M. Kobayashi;K. Uesugi;A. Takeuchi;K. Horikawa
利用X射线显微层析技术对几种铝合金中氢微孔及其高温生长行为进行了观察。高纯Al-Mg合金中观察到高密度的微孔，而纯铝中的微孔密度和体积分数要低得多。结果表明，微孔的生长行为主要受奥斯特瓦尔德熟化作用的控制。在低氢含量的Al-Mg合金中，约53%的氢被捕获在微孔中，使微孔成为主要的氢捕获场所。虽然总氢含量与合金中的氢含量相似，但纯铝中微孔中捕获的氢的比例低于7%。这种差异可归因于纯铝中氢沉淀位点的缺乏。虽然在位错和晶界的氢的总量是小的，在所有的材料中，这些陷阱网站的占有率被认为是非常高的。
X-ray microtomography was used to observe hydrogen micropores and their growth behavior at high temperatures in several aluminum alloys. High-density micropores were observed in high-purity Al–Mg alloys, but their density and volume fraction were much lower in pure aluminum. Our results have revealed that the growth behavior of micropores is dominated by Ostwald ripening. About 53% of hydrogen is trapped in micropores in Al–Mg alloy with low hydrogen content, making micropores the predominant hydrogen trap site. Although total hydrogen content is similar to that in the alloy, the ratio of hydrogen trapped in micropores is below 7% in pure aluminum. This difference is attributable to the lack of hydrogen precipitation sites in pure aluminium. Although the overall amounts of hydrogen at dislocations and grain boundaries are small in all the materials, the occupancies for these trap sites were concluded to be very high.