Correlations between stress corrosion cracking, grain boundary precipitates and Zn content of Al-Mg-Zn alloys
Correlations between stress corrosion cracking, grain boundary precipitates and Zn content of Al-Mg-Zn alloys
复制标题
Al-Mg-Zn合金应力腐蚀开裂、晶界析出物与Zn含量的相关性
DOI：
10.1016/j.jallcom.2015.09.159
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发表时间：
2016-01-15
影响因子：
6.2
通讯作者：
Zhang, Jishan
中科院分区：
文献类型：
--
作者：
Meng, Chunyan;Zhang, Di;Zhang, Jishan
采用慢应变速率法研究了Zn改性的传统Al-Mg合金在空气和HCl酸化至pH 3的3.5wt%NaCl溶液中的应力腐蚀开裂敏感性。传统的铝镁合金对晶间应力腐蚀开裂表现出严重的敏感性，而锌改性的铝镁合金对晶间应力腐蚀开裂没有敏感性。结果表明，在酸化NaCl溶液中添加Zn显著提高了合金的抗应力腐蚀开裂性能，并使合金从脆性破坏向完全韧性破坏转变。Zn的加入改变了Al Mg合金中晶界析出相和晶界取向差的分布。传统Al Mg合金中析出相沿晶界沿着连续分布，而Zn改性合金中析出相在基体中呈均匀分布，沿晶界沿着呈不连续分布。小角度晶界具有良好的抗晶间应力腐蚀开裂性能，即使沿晶界连续沿着析出。(C)2015 Elsevier B. V.版权所有。
The stress corrosion cracking susceptibility of traditional Al-Mg alloys modified by Zn was studied by using slow strain rate test both in the air and in 3.5 wt% NaCl solution acidified with HCl to pH 3. Traditional Al Mg alloys showed serious susceptibility to intergranular stress corrosion cracking, while Zn modified alloy showed relatively no susceptibility. It suggested that stress corrosion cracking resistance was significantly improved by Zn additions in acidified NaCl solution coupled with a transition from brittle failure to completely ductile failure. Both the distributions of grain boundary precipitations and grain boundary misorientation were modified by Zn addition to the Al Mg alloys. Traditional Al Mg alloys showed a continuous distribution of precipitations along the grain boundary, while Zn modified alloy showed a homogeneous precipitation in the matrix and discontinuous precipitation along the grain boundary. The low-angle grain boundaries had good resistance to intergranular stress corrosion cracking even though continuously precipitated along the grain boundary. (C) 2015 Elsevier B.V. All rights reserved.