Effect of heat input welding on microstructure and mechanical property of welded joint in V-N-Ti and Nb-Ti ship buliding steel
SHI Zhong-ran1,2, ZHAO Qing-kai3, LIU Deng-hui3, WANG Tian-qi1, CHAI Feng1
1. Department of Structural Steels, Central Iron and Steel Research Institute, Beijing 100081, China; 2. National New Material Production and Application Demonstration Platform Advanced Marine Engineering and High-tech Ship Materials, Beijing 100081, China; 3. Tianjing Branch, Cnooc China Limited, Tianjin 300452, China
Abstract:The effect of the heat input welding of 100 kJ/cm on microstructure and mechanical properties of the welded joint in V-N-Ti and Nb-Ti steel was studied. The results showed that the yield strength, tensile strength and elongation of the two kinds of steel were equivalent, while the impact energy at -40 ℃ of V-N-Ti steel was high than that of Nb-Ti steel. The impact energy at -20 ℃ of the heat-affected zone(CGHAZ) was equivalent to the two kinds of industrial steel, but the impact energy of weld metal of V-N-Ti steel was low than that of Nb-Ti steel. The CGHAZ microstructure of V-N-Ti steel was ferrite and bainite, and the heat-affected zone was narrow. The CGHAZ microstructure of Nb-Ti steel was bainite with a small amount of grain boundary ferrite.
师仲然, 赵庆凯, 刘登辉, 王天琪, 柴锋. 线能量对V-N-Ti和Nb-Ti船板焊接接头组织性能的影响[J]. 中国冶金, 2021, 31(1): 25-30.
SHI Zhong-ran, ZHAO Qing-kai, LIU Deng-hui, WANG Tian-qi, CHAI Feng. Effect of heat input welding on microstructure and mechanical property of welded joint in V-N-Ti and Nb-Ti ship buliding steel[J]. China Metallurgy, 2021, 31(1): 25-30.
Strid J,Easterling K E. On the chemistry and stability of complex carbides and nitrides in microalloyed steels[J]. Acta Metallurgica,1985,33(11):2057.
[10]
Wang G R,Lau T W,Weatherly G C,et al. Weld thermal cycles and precipitation effects in Ti-V-containing HSLA steels[J]. Metallurgical Transaction:A,1989,20(10):2093.
[11]
SHI Zhong-ran,YANG Cai-fu,WANG Rui-zhen,et al. Effect of nitrogen on the microstructures and mechanical properties in simulated CGHAZ of vanadium microalloyed steel varied with different heat inputs[J]. Materials Science and Engineering:A,2016,649:270.
[12]
Varughese R,Pense A W. Microstructural development in the coarse-grained,heat-affected zone in titanium-vanadium microalloyed HSLA steels[J]. Materials Characterization,1993,30(1):35.
[13]
Loberg B,Nordgren A,Strid J,et al. The role of alloy composition on the stability of nitrides in Ti-microalloyed steels during weld thermal cycles[J]. Metallurgical Transactions:A,1984,15(1):33.