【摘要】 为了探究X80M管线钢环焊缝填充层出现裂纹的原因,从焊材复验、焊接接头检测、裂纹分析以及模拟现场焊接试验等方面,采用化学成分、力学性能、扩散氢、硬度、光镜、扫描电镜等检测手段,对裂纹的产生原因展开了分析。结果发现,铜对裂纹的产生有重要影响。模拟现场焊接试验证实,现场焊接扩散氢含量要高于实验室所测扩散氢含量。通过一系列检测分析,最终明确焊缝中存在两种形式的裂纹,一种是铜导致的热裂纹,另一种是铜氢共同作用导致的冷裂纹。更多还原

【Abstract】 In order to explore the causes of cracks in the filler layer of X80 M pipeline steel girth welds, the crack production causes were analyzed by testing means of chemical composition analysis, mechanical property, diffusible hydrogen, hardness, optical microscopy and scanning electron microscope, etc.from the aspects of welding consumables re-inspection, welded joint detection, crack analysis and simulated on-site welding test.As a result, it was found that copper has an important influence on production of cracks.The on-site field welding experiment confirmed that the diffusible hydrogen content of on-site welding was higher than that measured in the laboratory.Through a series of testing and analysis, it is finally determined that there are two types of cracks in the weld.One is the hot cracks caused by copper, and the other is cold cracks caused by the combined action of copper and hydrogen.更多还原