危险蚀坑评判及疲劳寿命计算  

JUDGMENT OF CRITICAL PITS AND CALCULATION OF FATIGUE LIFE

作　　者：张川[1] 姚卫星[1] 

机构地区：[1]南京航空航天大学飞行器先进设计技术国防重点学科实验室,南京210016

出　　处：《机械强度》2013年第2期207-213,共7页Journal of Mechanical Strength

摘　　要：通过对在EXCO(exfoliation corrosion)溶液中加速腐蚀不同时间后的LC4CS试件表面腐蚀形貌进行观测,得到不同腐蚀时间下试件表面蚀坑深度及底部曲率半径。通过分析给出张开角的定义,并以此确定危险蚀坑及预测预腐蚀件的疲劳寿命。研究结果表明:张开角可以合理地确定危险蚀坑以及初始裂纹的等效尺寸。通过算例分析,用张开角来确定危险蚀坑可以较好地预测预腐蚀件的疲劳寿命。The corrosion morphology of specimens of aluminum alloy LC4CS soaked in EXCO （exfoliation corrosion） solution were examined by microscope to obtain depth of pits and radius of curvature at the bottom of pits with different pre-corrosion times. The definition of opening angle was proposed by analyzing experimental results, so the critical pits was determined and the pre-corrosion fatigue life was predicted based on the opening angle. Calculated life for example showed that opening angle could determine the critical pits and the equivalent dimension of initial crack. Examined by calculating an example, the critical pits determined by opening angle could be used to predict the pre-corrosion fatigue life reasonably.

关 键 词：预腐蚀 张开角 危险蚀坑 疲劳寿命 

分 类 号：TG146.21[一般工业技术—材料科学与工程] TG115.9[金属学及工艺—金属材料]