论文部分内容阅读
等效缺口应力法作为焊接疲劳分析的一种局部方法,不仅克服了焊接结构名义应力难以确定和焊根结构应力无法定义的困难,而且能够反映焊接局部后处理对焊接接头疲劳强度的影响,因此近年来备受关注。该文建立了典型焊接接头的三维缺口应力模型,对焊趾根部的缺口应力集中系数进行了求解;通过对对接接头和纵向角接头在焊后未处理(AS-weld)和超声喷丸处理(UPT)两种状态下的疲劳试验数据进行分析处理,获得了两种焊接接头在缺口应力系统下统一的S-N曲线,并与目前国际焊接学会所推荐的具有相同存活率的疲劳寿命曲线(IIW:m=3,FAT=225)进行比较,结果表明,该曲线具有更高的疲劳等级和更低的斜度。
As a local method of welding fatigue analysis, the equivalent notch stress method not only overcomes the difficulty of determining the nominal stress of the welded structure and the uncertainty of the root structure stress, but also reflects the influence of the welding post-processing on the fatigue strength of the welded joint In recent years, much attention. In this paper, a three-dimensional notch stress model of a typical welded joint is established, and the notch stress concentration coefficient at the root of the weld toe is solved. The AS-weld and ultrasonic shot peening UPT), the uniform SN curve of two kinds of welded joints under the notch stress system was obtained and compared with the fatigue life curve (IIW: m = 3, FAT = 225). The results show that the curve has a higher level of fatigue and a lower slope.