摘要
目的研究飞机某结构模拟试样加速腐蚀试验与自然暴露试验的相关性。方法选取飞机某结构模拟试样分别进行实验室加速腐蚀试验和海南西沙外场自然暴露试验,以宏/微观形貌、失光率、色差等级、腐蚀产物成分等作为评价指标,对试样表面涂层的腐蚀损伤情况进行长期观测和对比研究,对加速腐蚀2个周期和户外暴露2年的疲劳试样疲劳寿命和疲劳断口形貌进行对比分析。结果加速腐蚀试验2个周期和自然暴露试验2年试样的试验过程色差变化规律一致,色差变化等级均为2级,光泽度变化规律一致,加速腐蚀试验后为3级,户外自然暴露户外为4级、棚下为3级,在螺钉边缘均出现面漆剥落现象。7B04铝合金试样疲劳寿命断口的韧窝和孔洞的数量都没有发生明显的变化,在显著度为0.05时,两组疲劳寿命的t检验量为1.6971,疲劳寿命无显著差异。结论加速腐蚀试样表面涂层的腐蚀程度介于户外和棚下暴露试样之间,这一结果与加速环境谱的编制原则相一致,也进一步表明加速试验环境谱正确性。疲劳寿命无显著差异,表明加速腐蚀试验可以较好地模拟飞机实际工作环境对试样疲劳性能造成的影响。
The paper aims to study the correlation between accelerated corrosion test and natural exposure test of an aircraft structural simulation test specimen. Accelerated corrosion tests in laboratory and natural exposure tests in outfield of Xisha, Hainan province were carried out on a simulated aircraft structure. The macro/micro morphology, gloss reduction, chromatic aberration grade and composition of corrosion products were taken as evaluation indexes to compare the corrosion damage of surface coatings for a long time. The fatigue life and fracture morphology of fatigue specimens with two cycles of accelerated corrosion test and two years of outdoor exposure were compared and analyzed. The change rule of chromatic aberration in two cycles of accelerated corrosion test was consistent with that in two years of natural exposure test, and the change grade after test was 2. The gloss change regularity of the test process was the same, and the grade of gloss reduction was 3 after accelerated corrosion test. It was 4 in outdoor exposure and 3 under roof. Topcoat peeling occurred at screw edges. The number of dimples and holes of fatigue fracture of 7 B04 aluminium alloy specimens did not change significantly. When the significance was 0.05, the t-test value of fatigue life of the two groups was 1.6971, and there was no significant difference in fatigue life between the two groups. The corrosion degree of the topcoat of accelerated corrosion test specimens is between that of exposed test specimens in outdoor and under roof, which is consistent with the principle of accelerated environmental spectrum compiling. It further indicates the correctness of accelerated environmental spectrum. There is no significant difference in fatigue life, which indicates that accelerated corrosion test can properly simulate the impact of the actual working environment on the fatigue performance of aircraft specimens.
作者
卞贵学
张杨广
张勇
陈跃良
BIAN Gui-xue;ZHANG Yang-guang;ZHANG Yong;CHEN Yue-liang(Qingdao Campus of Naval Aviation University,Qingdao 266041,China;Unit 32102 of PLA,Yantai 265200,China)
出处
《装备环境工程》
CAS
2020年第5期25-32,共8页
Equipment Environmental Engineering
基金
国家自然科学基金资助项目(51375490)
山东省高等学校“青创科技计划”资助项目(2020KJA014)。
关键词
加速腐蚀
自然暴露
疲劳寿命
失光率
色差等级
accelerated corrosion
natural exposure
fatigue life
gloss reduction
chromatic aberration grade
