摘要
前起收放作动筒接头耳片损伤容限试验45 000次疲劳循环后,从预制缺口处第一次检测出裂纹,此时裂纹已接近穿透耳片厚度,未能采集到损伤容限数据。通过外观观察、断口宏微观观察及断口定量分析、金相组织观察、硬度和化学成分检测等手段,对接头耳片进行失效分析,并对检测方案进行改进。结果表明:接头耳片为疲劳开裂,裂纹萌生寿命为11 717循环周次,在裂纹萌生之后的扩展阶段至少4次渗透漏检;建议后期增加涡流无损检测配合渗透检测或选择在线检测,可有效地完成接头耳片的损伤容限试验。
A crack was detected at the pre-existing notch of the actuating cylinder joint lug during damage tolerance test after 45000 cycles. The crack had propagated through the wall thickness,and no effective damage tolerance data were obtained. In the present work,macro and micro observation,and quantitative analysis on fracture surface were carried out. In addition,hardness testing,metallurgical structure examination and chemical composition analysis were also performed. The results show the failure mode of the lug was fatigue cracking,and the crack initiation life was 11 717 cycles. The crack hadn＇t been found for at least 4 times during penetration testing. It is suggested that eddy current testing should be added or on-line detection should be applied so that damage tolerance testing can be effectively carried out.
出处
《失效分析与预防》
2015年第4期221-225,共5页
Failure Analysis and Prevention
关键词
作动筒接头耳片
损伤容限
渗透检测
断口定量分析
漏检
actuating cylinder joint lug
damage tolerance design
penetration testing
quantitative analysis
missing detection
