Microstructures and Plane Energy Spectra of X80 Pipeline Steel Welded Joints by Submerged Arc Automa

• 作 者: 孔德军 YE Cundong GUO Wei WU Yongzhong LONG Dan
• 机 构: College of Mechanical Engineering, Changzhou University,Jiangsu Key Laboratory of Materials Surface
• 出 处: Journal of Wuhan University of Technology(Materials Science
• 发表日期: 2014年06期
• 关键词: welded pipeline Pipeline Welding ferrite welding submerged sizes granular blocke

X80 pipeline steel was welded with submerged arc automatic welding, the microstructures, cavity sizes, fusion depths and plane scanning of chemical elements in the welded zone, fusion zone, heat affected zone and base steel were observed with OM(optical microscope) and SEM(scanning electron microscope), respectively. The experimental results show that there is main acicular ferrite in the base steel and welded zone, the microscopic structure of fusion zone is a blocked bainite, and the heat affected zone is composed of multilateral ferrite and pearlite. M-A unit of the welded zone is the main factor to strengthen the welded zone, composed of acicular ferrites. The percentage of cavities in the welded joint is less than that in the base steel, which is beneficial to increasing its mechanical performance and corrosion resistance. The fusion depth in the fusion zone and welded zone is 101.13 μm and 115.85 μm, respectively, and the distribution of chemical elements in the welded zone is uniform, no enrichment phenomena.

X80 pipeline steel was welded with submerged arc automatic welding, the microstructures, cavity sizes, fusion depths and plane scanning of chemical elements in the welded zone, fusion zone, heat affected zone and base steel were observed with OM (optical microscope) and SEM ( scanning electron microscope), respectively. The experimental results show there there is main acicular ferrite in the base steel and welded zone, the microscopic structure of fusion zone is a blocked bainite, and the heat affected zone is composed of ferrite and pearlite. MA unit of the welded zone is the main factor to strengthen the welded zone, composed of acicular ferrites. The percentage of cavities in the welded joint is less than that in the base steel, which is beneficial to increase its mechanical performance and corrosion resistance. fusion depth in the fusion zone and welded zone is 101.13 μm and 115.85 μm, respectively, and the distribution of chemical elements in the welded zone is uniform, no enrichment phenomena.