X80M高强韧性厚壁管线钢落锤撕裂试验试样异常断口形成原因及适用性分析  

Cause and Applicability Analysis on Abnormal Fracture of DWTT Sample of X80MHigh Strength and Toughness Thick Wall Pipeline Steel

作　　者：何小东 HE Xiaodong(CNPC Tubular Goods Research Institute,Xi’an 710077,China;State Key Laboratory of Service Behavior and Structure Safety for Petroleum Tubular Goods and Equipment Materials,Xi’an 710077,China)

机构地区：[1]中国石油集团石油管工程技术研究院,西安710077 [2]石油管材及装备材料服役行为与结构安全国家重点实验室,西安710077

出　　处：《理化检验（物理分册）》2020年第5期15-20,共6页Physical Testing and Chemical Analysis(Part A:Physical Testing)

基　　金：国家重点研发计划项目(2018YFC0310300)。

摘　　要：采用摆锤与落锤方式并配合高速摄像的方法,研究了X80M高强韧性厚壁管线钢落锤撕裂试验(DWTT)试样的断裂过程、吸收能量和断口形貌,并将DWTT试样断口与实物钢管爆破试验断口进行了对比。结果表明:对于X80M高强韧性厚壁管线钢,无论采取摆锤还是落锤锤击方式,在0℃时产生异常断口的几率相等;异常断口的形成原因是重锤的锤击作用使高强韧性厚壁管线钢产生了明显压缩塑性变形和形变硬化;异常断口不能真实表征材料性能,DWTT并不适用于高强韧性厚壁管线钢抗脆性断裂的能力评价。The fracture process,absorbed energy and fracture morphology of the sample of X80M high strength and toughness thick wall pipeline steel in drop weight tear test(DWTT)were studied by the method of using pendulum and drop hammer with high-speed camera,and the fracture of DWTT sample was compared with that of the real steel tube.The results show that for X80Mhigh strength and toughness thick wall pipeline steel,no matter the fracture was hammered by pendulum or drop hammer,the probability of abnormal fracture was equal at 0℃;the reason of abnormal fracture was that the impact of heavy hammer caused obvious compression plastic deformation and deformation hardening of high strength and toughness thick wall pipeline steel;the abnormal fracture couldn′t really characterize the material properties,and DWTT was not suitable for the evaluation of brittle fracture resistance of high strength and toughness thick wall pipeline steel.

关 键 词：管线钢 高强韧性 落锤撕裂试验 异常断口 压缩塑性变形 

分 类 号：TG335.5[金属学及工艺—金属压力加工]