基于微观结构的航空铝合金点蚀扩展行为研究

点蚀是航空铝合金材料在服役环境下常见的损伤形式,在疲劳载荷作用下容易形成裂纹,缩短结构的疲劳寿命。为了深入研究点蚀对航空铝合金结构腐蚀疲劳寿命的影响,基于铝合金电化学腐蚀机理和铝合金微观结构,以点蚀蚀坑尺寸为研究参量,对航空铝合金点蚀扩展行为进行建模研究,并将模型计算结果与LY12CZ铝合金点蚀试验结果进行对比分析。结果表明:所构建的铝合金点蚀扩展模型较为合理地反映了铝合金点蚀蚀坑尺寸参数的变化规律。

Research of Aero Aluminum Alloys Pitting Corrosion Growth Behavior Based on Microstructure

Pitting corrosion is a typical damage of aircraft aluminum alloys structure in the service environment which could initiate crack under the fatigue load and shorten the structure fatigue life.In order to fully understand the function mehcanism of the pitting corrosion to the corrsion fatigue life ,the growth behavior of aluminum alloy pitting corrosion should be studied.Based on the electrochemical corrosion mechanism and the microstructure, the size of corrosion pit was chosen as research parameter, the model of aluminum alloy pitting corrosion growth behavior was researched, and the result between model calculating and the LY12CZ pitting corrosion test was comparatively analyzed, which showed that the established model could reasonably reflect the evolution rule of aluminum alloy corrosion pit size parameter.