论文部分内容阅读
针对管线钢管先内焊后外焊工艺,采用Gleeble3500热模拟试验机研究了外焊不同峰值温度对X100管线钢及其内焊缝组织与性能的影响。结果表明:当外焊峰值温度为1300℃时,母材和内焊缝的韧性大幅下降,硬度上升,在粗晶区均出现了脆化现象,母材韧性损失42%,焊缝韧性损失84%,成为焊接接头韧性最差的区域。同时,在外焊峰值温度为860℃时,母材和内焊缝的韧性也有明显降低。组织分析表明,粗大的、链状M/A岛是韧性变差的主要原因。
Aiming at the first internal welding process of pipeline steel after internal welding, the influence of different peak temperature of external welding on microstructure and properties of X100 pipeline steel and its internal weld was studied by using Gleeble3500 thermal simulation testing machine. The results show that the toughness of base metal and internal weld decreases sharply when the peak temperature of external welding is 1300 ℃, and the hardness increases. The embrittlement occurs in the coarse grain region, the loss of toughness of base metal is 42% and the loss of toughness of weld is 84 %, Become the worst toughness of welded joints. At the same time, the toughness of the base metal and the internal weld is also significantly reduced at a peak temperature of 860 ° C. Tissue analysis showed that coarse, chain M / A island is the main reason for the deterioration of toughness.