Q345桥梁钢超长寿命疲劳性能研究
首发时间:2009-04-21
摘要:本文采用超声振动疲劳技术研究了波纹钢腹板的主要材料Q345qC钢的高周与超高周疲劳性能。实验在常温下进行,实验应力比R=-1,系统共振频率20kHz,采用沙漏形试样。实验获得了Q345qC钢在105~109范围内的S-N曲线,并用电子显微镜分析了疲劳断口形貌特征。结果发现S-N曲线未出现水平渐近线,而是呈现连续下降,在107周次以后,试样仍然发生疲劳破坏,并不存在传统意义上的疲劳极限。超声疲劳断口的扫描电子显微分析结果表明,Q345qC钢材疲劳损伤时裂纹起源于构件表面或试样内部缺陷。
关键词: 波形钢腹板 Q345qC 超声振动疲劳 S-N曲线 断口特征
For information in English, please click here
uper Long Life Fatigue Behaviors of Q345 Bridge Steel
Abstract:Q345qC steel is widely used in corrugated steel web. In this paper, the fatigue behavior of Q345qC steel between 105~109 was studied using the ultrasonic fatigue testing technique, with a loading frequency of about 20 kHz. The fracture surfaces of specimens were investigated with scanning electron microscopy (SEM). The experimental results show that the S-N curve of Q345qC steel continues to decrease with the increase of the number of cycles between 105 and 109 cycles and does not generally exhibit a plateau beyond 107 cycles. The observation of fracture surface shows that the mechanism of fatigue failure is similar in both case of ultrasonic fatigue and conventional fatigue in long life regime. Cracks initiate from a mass defect of specimen surface or an interior inclusion.
Keywords: Corrugated steel web Q345qC Ultrasonic fatigue test S-N curve Fracture surface
论文图表:
引用
No.3160146356712403****
同行评议
共计0人参与
勘误表
Q345桥梁钢超长寿命疲劳性能研究
评论
全部评论0/1000