Effects of polarisation on mechanical properties and stress corrosion cracking susceptibility of 7050 aluminium alloy

作者：Qi X; Song R G^*; Qi W J; Jin J R; Wang C; Li H

来源：Corrosion Engineering, Science and Technology, 2014, 49(7): 643-650.

DOI：10.1179/1743278214Y.0000000162

• 7050 aluminium alloy
• Mechanical properties
• Stress corrosion cracking
• Polarisation
• Slow strain rate test

The effects of polarisation (including cathodic and anodic polarisation) on mechanical properties and stress corrosion cracking (SCC) susceptibility (I-SCC) of 7050 aluminium alloy have been investigated by means of polarisation and slow strain rate test. The results of cathodic polarisation experiments showed that the I-SCC increased with shifting negatively the polarisation potential when the cathodic potential E-C >= -1100 mV(SCE), while it decreased with shifting negatively the polarisation potential when the cathodic potential E-C < -1100 mV(SCE). Anodic polarisation experiments demonstrated that the I-SCC increased severely with increasing the polarisation potential. In addition, the extents for the effect of polarisation potential on I-SCC were different among the 7050 aluminium alloy under various aging states. Polarisation was of the biggest effect on the I-SCC of under aged state, the smallest effect of over aged state and the middle effect of peak aged state. The SCC mechanism of aluminium alloy was a combination of anodic dissolution and hydrogen embrittlement, and the effects of hydrogen on SCC increased with increasing the hydrogen concentration.

• 出版日期2014-10
• 单位常州大学