Microstructure and Mechanical Property of High-nitrogen Steel with GMAW Welding Wires with Different Nitrogen Contents

doi:10.3969/j.issn.1000-1093.2021.06.021

Abstract

Abstract: In order to study the structures and properties of high-nitrogen steel welds with different nitrogen content welding wires, three kinds of welding wires with different nitrogen contents of 0.46［N］,0.61［N］ and 0.84［N］ were used in gas metal arc welding (GMAW) tests of high-nitrogen steel, and the nitrogen fixation effect, porosity, microstructure and mechanical properties of the welds were tested and analyzed. The results show that, as the nitrogen content of welding wire increases, the nitrogen content of weld increases, and the porosity tendency increases; the microstructures of three welding wires are composed of austenite and ferrite, the microstructure of weld is mainly determined by the solidification mode of weld, which is determined by the joint action of various alloying elements in the weld; and the mechanical properties of welds are mainly affected by the content and distribution of ferrite. The higher the ferrite content and the distribution along the grain are, the higher the hardness and strength of the weld are, and the worse the toughness is. When the weld solidification mode is A or AF, the nitrogen content of the weld is higher, the tensile property of the weld is better. The pore defect mainly affects the impact toughness of the weld, and the increase in pores reduces the impact toughness of the weld.

Key words: high-nitrogensteelweldingwire, gasmetalarcwelding, nitrogencontent, microstructuremechanicalpropertiy, mechnicalproperty

CLC Number:

TG422.3

MA Liangchao, WANG Dafeng, MA Bing, CHEN Donggao, ZHANG Yingying. Microstructure and Mechanical Property of High-nitrogen Steel with GMAW Welding Wires with Different Nitrogen Contents[J]. Acta Armamentarii, 2021, 42(6): 1303-1311.

References

［1］ STEIN G, HUCKLENBROICH I. Manufacturing and applications of high nitrogen steels[J]. Materials and Manufacturing Processes, 2004,19(1): 7-17.
[2］ KAPUTKINA L M, SVAZHIN A G, SMARYGINA I V, et al. Corrosion and cavitation resistance of high-strength austenitic nitrogen stainless steels in seawater[J]. Steel in Translation, 2019, 49(1): 13-19.
[3］ BAYOUMI F M, GHANEM W A. Effect of nitrogen on the corrosion behavior of austenitic stainless steel in chloride solutions[J]. Materials Letters, 2005, 59(26): 3311-3314.
[4］ LI J, LI H, LIANG Y, et al. The microstructure and mechanical properties of multi-strand, composite welding-wire welded joints of high nitrogen austenitic stainless steel[J]. Materials, 2019, 12(18): 2944.
[5］ HOSSEINI V A, WESSMAN S, HURTIG K, et al. Nitrogen loss and effects on microstructure in multipass TIG welding of a super duplex stainless steel[J]. Materials & Design, 2016, 98: 88-97.
[6］胡秋月. 铬镍奥氏体不锈钢的焊接质量问题及对策[J]. 装备制造技术, 2016(3): 109-110.
HU Q Y .Welding quality problems and countermeasures of chromium nickel austenitic stainless steel[J]. Equipment Manufacturing Technology, 2016(3): 109-110.（in Chinese）
[7］荆皓, 王克鸿, 强伟，等. 氮含量对高氮钢PMIG焊接头组织和性能的影响[J]. 焊接学报, 2017, 38(4):95-98.
JING H, WANG K H, QIANG W, et al. Influence of N-content on microstructure and mechanical properties of PMIG welding joints of high nitrogen steel[J]. Transactions of the China Welding Institution, 2017, 38(4):95-98. （in Chinese）
[8］ KAMIYA O, CHEN Z W, KIKUCHI Y. Microporosity formation in partially melted zone during welding of high nitrogen austenitic stainless steels[J]. Journal of Materials Science, 2002, 37(12):2475-2481.
[9］ ZHAO L, TIAN Z L, PENG Y, et al. Influence of nitrogen and heat input on weld metal of gas tungsten arc welded high nitrogen steel[J]. Journal of Iron and Steel Research, International, 2007, 14(5):259-262.
[10］刘昂. 高氮钢MIG焊焊缝增氮及接头组织性能研究[D]. 哈尔滨:哈尔滨工业大学,2015.
LIU A. Research of adding nitrogen to welded metal and microstructure and properties of high nitrogen steel MIG welded joint[D]. Harbin: Harbin Institute of Technology, 2015. （in Chinese）
[11] 颜泽钢. 高氮奥氏体不锈钢氮氩混合气保焊焊接工艺试验研究[D]. 南京：南京理工大学，2016.
YAN Z G. Researching on welding process of high nitrogen austenitic stainless steel with N-Ar mixed protecting gas[D]. Nanjing: Nanjing University of Science and Technology，2016.（in Chinese）
[12］崔博, 张宏, 刘双宇, 等. 高氮钢复合焊接接头氮含量和气孔控制方法研究[J]. 兵工学报, 2019,40(11):2311-2318.
CUI B, ZHANG H, LIU S Y, et al. Research on control method of nitrogen content and porosity in hybrid welding joint of high nitrogen steel[J].Acta Armamentarii, 2019,40(11):2311-2318. （in Chinese）
[13］明珠，王克鸿，王伟，等. 焊丝含氮量及焊接电流对高氮钢焊缝组织和性能影响[J]. 焊接学报, 2019, 40(1): 104-108.
MING Z, WANG K H, WANG W, et al. Effects of nitrogen content and welding current on microstructure and properties of the weld of high nitrogen austenite steel[J]. Transactions of the China Welding Institution, 2019, 40(1):104-108. （in Chinese）
[14］明珠，王克鸿，王伟，等. 冷却速率对高氮钢焊缝组织和性能的影响[J]. 焊接学报, 2019, 40(10): 31-35.
MING Z, WANG K H, WANG W, et al. Effect of cooling rate on the microstructure and mechanical properties of high nitrogen stainless steel weld metal [J]. Transactions of the China Welding Institution,2019, 40(10):31-35.（in Chinese）
[15］辛秀成. 复合焊接的焊丝氮元素熔池过渡机理研究[D].长春：长春理工大学,2018.
XIN X C. Effect of the different nitrogen content in welding wire on microstructure and mechanism for hybrid welding[D].Changchun：Changchun University of Science and Technology, 2018. （in Chinese）
[16］ WOO I, KIKUCHI Y. Weldability of high nitrogen stainless steels[J]. ISIJ International, 2002, 42(12): 1334-1343.
[17］ SCHINO A D, MECOZZI M G, BARTERI M, et al. Solidification mode and residual ferrite in low-Ni austenitic stainless steels[J]. Journal of Materials Science, 2000, 35(2):375-380.