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前一篇论文[1]讨论了根部缺陷对用AlMg(NG61)和AlSi(NG21)两种焊丝材料焊接的Al-Zn-Mg合金十字形角焊缝疲劳性能的影响。根据擅自规定的不同的施工质量水平——这些质量水平被规定为S-N曲线图中的某区域——推导出许可的缺陷尺寸。因为一般认为焊接接头的疲劳寿命主要由裂纹的部分扩展而不是由裂纹的起始部分构成,故Paris Erdogan律已被用于预测寿命,而且特别被推荐为一种确定临界缺陷尺寸的合理的方法;据此,对这些以前引用过的结果[1]进行了这类适用的分析,只是还必须在测量疲劳裂纹扩展速率方面进一步做些试验工作,从而确定这种断裂力学方法在预测中强度AlZnMg合金角焊缝疲劳性能和根部缺陷的影响方面的有效性。
The previous paper [1] discussed the effect of root defects on the fatigue properties of Al-Zn-Mg alloy cross-fillet welds welded with two wire materials AlMg (NG61) and AlSi (NG21). Depending on the different levels of construction quality that are prescribed without authorization - these levels of quality are specified as a region in the S-N graph - the permitted defect size is derived. The Paris Erdogan law has been used to predict life expectancy because it is generally considered that the fatigue life of a weld joint is primarily caused by the partial expansion of the crack rather than the initial portion of the crack and is especially recommended as a reasonable method of determining the critical defect size ; Accordingly, a suitable analysis of these previously cited results [1] has been made except that further testing of the fatigue crack growth rate has to be done to confirm that this fracture mechanics method is predictive of the strength of AlZnMg The effectiveness of the fillet weld fatigue properties and root defects.