X65管线钢焊接接头CTOD断裂韧度  

CTOD fracture toughness of welded joints of X65 pipeline steel

作　　者：邓彩艳[1] 张玉凤[1] 霍立兴[1] 白秉仁[2] 李小巍[2] 曹军[2] 

机构地区：[1]天津大学材料科学与工程学院,天津300072 [2]海洋石油工程股份有限公司,天津塘沽300452

出　　处：《焊接学报》2003年第3期13-16,共4页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目 ( 5 9975 0 66);中国海洋石油工程股份有限公司资助项目

摘　　要：根据BS74 4 8断裂韧度试验标准 ,对X6 5管线钢焊接接头的低温 (0℃ )裂纹尖端张开位移 (CTOD)进行了测试。取尺寸为B× 2B(B为试样厚度 )、缺口方向为NP的试样进行三点弯曲试验 ,然后由所得到的 0℃下母材、焊缝和热影响区 (HAZ)的P -V曲线来计算CTOD值 ,并对试验结果进行了讨论和总结。对显微组织的分析表明 ,共有3个HAZ试件不满足裂纹尖端不超过熔合线 0 .5mm且落在粗晶区内的要求。该结果恰好与P -V曲线和所得的CTOD值相一致 ,从而解决了试验值分散性大的问题 ,同时为ECA评估提供了重要依据 ,验证了BS74 4 8标准的合理性并体现了它的优越性。In accordance with the BS 7448, fracture toughness test standard, CTOD (crack tip opening displacement) tests were conducted at 0°C in welded joints of X65 pipeline steel. According to the requirements of the standard, the specimen is of standard three-point bending shape that has a rectangular section of B×2B and notch orientation of NP. The results were calculated by using the P-V curves of parent material, weld metal and HAZ (heat affected zone). It indicates by the microstructure that there are 3 HAZ specimens of which the fatigue crack lip is not more than 0.5 mm from the fusion line with coarse grain zone. The test results are in consistence with the P-V curves and CTOD values, explaining the dispersity of the test values, providing reliable evidence for engineering critical assessment and validate the BS7448 and its superiority.

关 键 词：X65管线钢 焊接接头 裂纹尖端张开位移 断裂韧度 CTOD 海底油气管道 

分 类 号：TE973.3[石油与天然气工程—石油机械设备] TG404[金属学及工艺—焊接]