Hydrogen-environment Embrittlement in High-purity Al-Zn-Mg(-Cu) Alloys
From the viewpoint of a both practical and basic understanding on hydrogen-environment embrittlement (HEE) of high-strength aluminum alloys, high-purity Al-Zn-Mg(-Cu) alloys having contents of primary alloying elements comparable to 7075 alloy are subjected to slow strain rate tensile (SSRT) tests in a high-pressure hydrogen gas and atmospheric air with a controlled relative humidity. The characteristics of HEE have been studied as a function of aging stage, strain rate and test temperature. From the test results on the Al-Zn-Mg ternary alloy in the underaged (UA) with a high sensitivity to HEE, it is confirmed that humid air is so severer than highpressure gaseous hydrogen to cause embrittlement in aluminum alloys. An increase in each of humidity and temperature of atomospheric air increases the susceptibility to HEE, leading to a remarkable intergranular cracking. The copper-bearing alloy having a higher tensile strength in the peak-aging (PA) state than the ternary alloy exhibits a superiority in the HEE resistance too. For the overaged (OA) cupper-bearing alloy, the higher humidity of air produces the higher elongation and a transgranular dimple fracture, which suggest that the void formation becomes easier by hydrogen trapping at coarsened precipitate particles within grains.
Al-Zn-Mg-(Cu) alloy Hydrogen embrittlement Hydrogen gas Humid air SSRT test
Shogo Itonaga Shigeyuki Haruyama Ken Kaminishi Shuhei Osaki
Graduate school of Science and Engineering, Yamaguchi University, Ube-shi, Yamaguchi Graduate school of Management of Technology, Yamaguchi University, Ube-shi, Yamaguchi
国际会议
The 8th International Conference on Innovation and Management(第八届创新与管理国际会议 ICIM 2011)
日本福冈
英文
269-272
2011-11-30（万方平台首次上网日期，不代表论文的发表时间）