X70管线钢管环焊接头在低约束条件下的断裂韧性  

Fracture Toughness of X70 Steel Pipeline Girth Weld under Low Constraint Condition Joint

作　　者：唐家睿 陈宏远[2,3] 高惠临[1] 吉玲康[1,2] 

机构地区：[1]西安石油大学材料科学与工程学院,西安710065 [2]中国石油集团石油管工程技术研究院,西安710077 [3]西安交通大学材料科学与工程学院,西安710049

出　　处：《机械工程材料》2016年第3期27-30,34,共5页Materials For Mechanical Engineering

基　　金：中国石油科技创新基金资助项目(2013D-5006-0602)

摘　　要：针对基于应变设计的X70管线钢管,采用单边缺口拉伸试验对该钢钢管环焊缝金属及热影响区的裂纹尖端张开位移进行研究,获得了裂纹延性扩展过程的断裂阻力曲线,并对热影响区试样的试验结果进行了有效性验证。结果表明:热影响区试样的裂纹尖端距熔合线的距离在0.5mm以内,焊缝金属和热影响区试样的断裂阻力曲线分别为δ=1.395 78(Δa)0.783 35,δ=1.553 38(Δa)0.821 75;采用单边缺口拉伸试验能准确测出管线钢环焊接头在低约束条件下的断裂韧性;试验结果可以为管线基于应变设计和工程临界评价提供依据。The single-edge-notched-tensile（SENT）test was carried out on strain-based design of X70 steel pipeline to measure crack tip opening displacement of girth weld metal and heat affected zone.The fracture resistance curves during crack ductile extension process were obtained and tested results of heat affected zone sample were validated.The results show that the distance from crack tip of heat affected zone sample to fusion line was within 0.5 mm.Fracture resistance curves of weld metal and heat affected zone samples as followed：δ =1.395 78（Δa）0.783 35,δ=1.553 38（Δa）0.821 75.Fracture toughness of pipeline girth weld under low constraint condition can be accurately measured by SENT test.The tested results can provide evidence for strain-based design pipeline and engineering critical assessment.

关 键 词：X70管线钢 环焊接头 裂纹尖端张开位移 单边缺口拉伸试验 断裂阻力曲线 

分 类 号：TG404[金属学及工艺—焊接]