不同环境压力下X65管线钢焊接接头的组织及硬度  

Microstructure and Hardness of Welding Joints of X65 Pipeline Steel Under Different Environmental Pressures

作　　者：王瑜[1] 黄继强[2] 薛龙[2] 张忠明[1] 

机构地区：[1]西安理工大学材料科学与工程学院,陕西西安710048 [2]北京石油化工学院光机电装备技术北京市重点实验室,北京102617

出　　处：《铸造技术》2016年第10期2193-2196,共4页Foundry Technology

基　　金：国家自然科学基金(51275051);光机电装备技术北京市重点实验室开放课题基金(KF2013-01)资助项目

摘　　要：对API X65管线钢进行模拟高压干法水下焊接,对不同环境压力条件下(0.1,0.3,0.5,0.7 MPa)焊接接头的显微组织及硬度进行测试,分析环境压力对焊接接头组织和性能的影响。结果表明:X65管线钢的组织由铁素体、珠光体和上贝氏体组成。不同环境压力下焊缝的显微组织均为铁素体、珠光体和少量的碳化物;热影响区的组织均为针状铁素体和少量的珠光体。热影响区熔合线附近的硬度较高,远离融合线处硬度降低,并逐渐接近母材金属的硬度。环境压力对焊接接头的显微组织及硬度的影响不大。A X65 pipeline steel was welded by simulated underwater hyperbaric dry welding.The microstructure and hardness of welded joints in different environmental pressures were studied.The results show that the microstructure of the X65 pipeline steel consists of ferrite,pearlite and upper bainite.The microstructures of the weld seam under different environmental pressures consists of ferrite,pearlite and a few carbides.The microstructure of the HAZ is composed of acicular ferrite and a small amount of pearlite.The hardness near the weld bond of HAZ is higher and decreases away from it,and gradually approaching to the hardness of the base metal.The environmental pressure has little effect on the microstructure and hardness of the welded joints.

关 键 词：X65管线钢 高压干法水下焊接 环境压力 显微组织 硬度 

分 类 号：TG456.5[金属学及工艺—焊接]