摘要
采用恒载荷全浸腐蚀拉伸、断口扫描和室温拉伸等方法研究了拉应力对两种热处理状态6061铝合金(6061-T4和6061-T6)应力腐蚀行为的影响。结果表明,在O2和Cl-共存环境中,6061-T4铝合金的应力腐蚀敏感性很低,力学性能降低主要受腐蚀介质的电化学腐蚀影响;6061-T6铝合金的应力腐蚀开裂敏感性高于6061-T4铝合金,其应力腐蚀开裂倾向受腐蚀影响为主,力学因素影响为辅;应力腐蚀后,6061-T4和6061-T6铝合金表层腐蚀区域为沿晶脆断,次表层为准解离断裂,中心为穿晶断裂;在腐蚀介质与应力同时作用下,6061-T4铝合金由点蚀发展为晶间腐蚀,并随应力增大变为剥落腐蚀;6061-T6铝合金点蚀不明显,但晶间腐蚀深度随应力增大而加深。
The effect of tensile stress on stress corrosion properties of aluminum alloy at different heat-treatment states(6061-T4 and 6061-T6)were studied by means of constant load full immersion corrosion tensile,fracture scanning and room temperature tensile methods.The results showed that in the coexistence of O2 and Cl-,the stress corrosion sensitivity of 6061-T4 aluminum alloy was very low,and the degradation of mechincal properties was mainly affected by the electrochemical corrosion of corrosive medium.The stress corrosion cracking sensitivity of the 6061-T6 aluminum alloy was higher than that of the 6061-T4 aluminum alloy,and the stress corrosion cracking tendency of the 6061-T6 aluminum alloy were mainly affected by corrosion and supplemented by mechanical factors.The surface corrosion areas of both aluminum alloys after stress corrosion were intergranular brittle fracture,the subsurfaces were quasi-dissociative fracture,and the centers were transgranular fracture.Under the simultaneous action of corrosive medium and stress,the corrosion of 6061-T4 aluminum alloy developed from pitting corrosion to intergranular corrosion,and finally became exfoliation corrosion as the stress increased.Pitting corrosion in 6061-T6 aluminum alloy was not obvious,but the depth of intergranular corrosion increased with stress.
作者
何祯
拜斌
张小明
孟嘉琳
HE Zhen;BAI Bing;ZHANG Xiaoming;MENG Jialin(AVIC The First Aircraft Institute,Xi'an 710000,China;The Naval Armaments Department Military Representative Office in Xi'an Area,Xi'an 710000,China)
出处
《腐蚀与防护》
CAS
CSCD
北大核心
2023年第2期64-69,共6页
Corrosion & Protection
关键词
6061铝合金
应力腐蚀
恒载荷
热处理状态
6061 aluminum alloy
stress corrosion
constant load
heat treatment state
