Zhang Shuchang, Wang Honghong, Wang Yangwen, Cao Liang
College of Science, Wuhan University of Science and Technology, Wuhan 430081, China.
The State Key Laboratory of Refractories and Metallurgy, Wuhan University of Science and Technology, Wuhan 430081, China.
Materials (Basel). 2023 Mar 16;16(6):2381. doi: 10.3390/ma16062381.
The novel high-Mn austenitic steel is becoming a promising steel for cryogenic applications of LNG tanks. The welded joints take a critical role in cryogenic service for storage tanks. In this work, we developed well-matched high-Mn welding consumables and prepared the welded joints by shielded metal arc welding (SMAW), submerged arc welding (SAW) and gas tungsten arc welding (GTAW). The detailed welding parameters were proposed first, then the welding quality, mechanical properties, and microstructure were investigated. The results show that good welding quality, excellent mechanical properties, and stable levels of mechanical properties were obtained for high-Mn steel welded joints using similar welding consumables, the solid core of electrodes, and solid welding wires. Notably, the lowest cryogenic absorbed energy was found at 5 mm away from the fusion line rather than at the fusion line. The hardness of the welded joints was detected to be less than 280 HV due to the whole austenitic microstructure.
新型高锰奥氏体钢正成为一种有望用于液化天然气储罐低温应用的钢材。焊接接头在储罐的低温服役中起着关键作用。在这项工作中，我们开发了匹配良好的高锰焊接材料，并通过手工电弧焊（SMAW）、埋弧焊（SAW）和钨极气体保护电弧焊（GTAW）制备了焊接接头。首先提出了详细的焊接参数，然后研究了焊接质量、力学性能和微观结构。结果表明，使用相似的焊接材料、实心焊条和实心焊丝对高锰钢焊接接头进行焊接，可获得良好的焊接质量、优异的力学性能以及稳定的力学性能水平。值得注意的是，最低的低温吸收能量出现在距熔合线5mm处，而非熔合线处。由于整个奥氏体微观结构，焊接接头的硬度检测值小于280HV。
