摘要
采用疲劳试验、腐蚀实验、SEM及EDS等分析测试手段,研究2E12铝合金标准中心裂纹试件在加速腐蚀环境谱下的疲劳裂纹扩展,该谱的1个周期包括温湿、热冲击、室温疲劳和盐雾4个环境块。利用修正的Paris公式分析,发现试样在加速谱环境下合金的疲劳裂纹扩展较实验室环境明显加速。合金的疲劳裂纹扩展主要呈现腐蚀疲劳特征。讨论了加速谱对合金疲劳裂纹扩展的影响,其中盐雾、湿热环境下的氢脆导致塑性区脆化及腐蚀诱导的阳极溶解是导致裂纹扩展、性能降低的主要原因。
Experiments with CCT specimens of 2E12-T4 aluminum alloy were conducted under accelerated test environment spectrum,which was composed of hot-humid environment,thermal impingement,room temperature fatigue and salt spray,and the results were analyzed by scanning electron microscopy（SEM） and X-ray energy-dispersive spectroscopy（EDS）.The growth rates of fatigue crack under lab air and the spectrum environments were analyzed and compared with modified Paris equation.It＇s found the fatigue crack growth（FCG） speeds up markedly under the spectrum and the alloy mainly presents corrosion fatigue feature.The effects and mechanism related with the spectrum on FCG of 2E12 were discussed.The increased crack growth rate is mainly due to a combination of hydrogen embrittlement and anodic dissolution at the crack tip under the salt spray and hot-humid environment.
出处
《材料科学与工程学报》
CAS
CSCD
北大核心
2009年第5期770-773,共4页
Journal of Materials Science and Engineering
基金
国家973重点基础研究发展规划资助项目(2005CB623705)
关键词
2E12铝合金
疲劳裂纹扩展
加速腐蚀环境谱
2E12 aluminum alloy
corrosion
fatigue crack growth
accelerated corrosive environment spectrum
