Please wait a minute...
Acta Metall Sin  2017, Vol. 53 Issue (5): 631-640    DOI: 10.11900/0412.1961.2016.00263
Orginal Article Current Issue | Archive | Adv Search |
Numerical Simulation of Physical Characteristics of Variable Polarity Plasma Arc Welding
Shujun CHEN,Bin XU,Fan JIANG()
Engineering Research Center of Advanced Manufacturing Technology for Automotive Components, Ministry of Education, Beijing University of Technology, Beijing 100124, China
Cite this article: 

Shujun CHEN,Bin XU,Fan JIANG. Numerical Simulation of Physical Characteristics of Variable Polarity Plasma Arc Welding. Acta Metall Sin, 2017, 53(5): 631-640.

Download:  HTML  PDF(3720KB) 
Export:  BibTeX | EndNote (RIS)      
Abstract  

Variable polarity plasma arc (VPPA) is a kind of source to provide heat and force at welding process. It can remove the oxide layer with high melting point on the surface of base metal using the cleaning action of cathode spots (the special property of VPPA). So variable polarity plasma arc welding (VPPAW) is a very suitable method to join aluminum alloys which always have extremely tenacious surface oxides. It is great significant to understand clearly the physical characteristics of VPPA for predicting welding defects and making the welding process stable. Therefore, modeling and simulating VPPA are necessary and helpful to understand welding process theory and promote its application further. In this work, a three dimensional transient calculated model of VPPA was established. To describe the electrical characteristics of VPPA at different polarities, a sequential electric conducting model was proposed. With finite difference method, the temperature field, fluid flow and current density of VPPA were solved out. And the distribution of plasma arc pressure on the anode surface, as well as its evolution process as the time going on were analyzed. Arc pressure was measured experimentally to verify the calculated model. The results show that the arc temperature field of electrode negative (EN) is more compressed than that of electrode positive (EP). The range of high temperature at EN is a little larger. Arc pressure and current density of EN at central area are both higher than EP. Nonetheless, the magnitude of these values begins to reverse at a certain distance to center in radial direction. Moreover, the arc pressure rapidly responses to welding current. Pressure at EP is about 20% lower than that of EN. The pressure reduces to the lowest value when the current pass through 0. After that, while the current reaches to normal value, the pressure will immediately impact to a larger value, then quickly recover to an average value. Otherwise, to compare the experimental results with calculated results of arc images and arc pressure, they are in good agreement with each other.

Key words:  variable polarity plasma arc      three dimensional model      numerical simulation     
Received:  27 June 2016     
Fund: Supported by National Natural Science Foundation of China (No.51505008) and National Science and Technology Major Project of China (No.2014ZX04001-171)

URL: 

https://www.ams.org.cn/EN/10.11900/0412.1961.2016.00263     OR     https://www.ams.org.cn/EN/Y2017/V53/I5/631

Fig.1  Measure system of arc pressure and image of variable polarity plasma arc (VPPA)
Fig.2  Schematic of VPPA at different polarities (EN—electrode negative, EP—electrode positive)
Fig.3  Solution area and boundary conditions
Boundary v / (ms-1) T / K ? / V A / (Wbm-1)
ABC ?v?n=0 1000 ?=?VPPA ?A?n=0
APOTXUQLGFEDC, APNSWVRMHIJKB ?v?n=0 ?T?n=0 ???n=0 ?A?n=0
LGHM, XTONSW, UQLMRV, FGHI, DEJK - 1000 ???n=0 ?A?n=0
OPN - 3000 Eqs.(10)~(13) ?A?n=0
UXWV, EFIJ v=vconstant 1000 ???n=0 ?A?n=0
CBKD ?(ρv)?n=0 1000 ???n=0 0
Table 1  Boundary conditions
Fig.4  Temperature and flow field distributions of VPPA at EN (a) and EP (b)
Fig.5  Radial temperature distributions of VPPA (x=7 mm)
Fig.6  Radial pressure distributions of VPPA (x=7 mm)
Fig.7  Plasma velocity distributions of VPPA at the axis
Fig.8  Radial current density distributions of different polarities at work-piece surface
Fig.9  Surface morphology of aluminum alloy
Fig.10  Images of VPPA at EN (a) and EP (b)
Fig.11  Evolution of arc pressure at the center of VPPA
[1] Jenney C L, O'Brien A. Welding Handbook[M]. 2nd Ed., Miami: American Welding Society, 2001: 309
[2] Nunes A C Jr, Bayless E O Jr, Jones C S III, et al. Variable polarity plasma arc welding on the space shuttle external tank[J]. Weld. J., 1984, 63: 27
[3] Chen Q, Sun Z G, Sun J W, et al.Closed-loop control of weld penetration in keyhole plasma arc welding[J]. Trans. Nonferrous Met. Soc. China, 2004, 14: 116
[4] Dong C L, Zhu Y F, Zhang H, et al.Study on front side arc light sensing in keyhole mode plasma arc welding[J]. China Mech. Eng., 2001, 37(3): 30
[4] (董春林, 朱轶峰, 张慧等. 穿孔等离子弧焊正面弧光传感技术研究[J]. 机械工程学报, 2001, 37(3): 30)
[5] Satoru S.Sensing technology for the welding process[J]. Weld. Int., 2006, 20: 183
[6] Thornton M F.Spectroscopic determination of temperature distributions for a TIG arc[J]. J. Phys. Appl. Phys., 1993, 26D: 1432
[7] Haidar J, Farmer A J D. Temperature measurements for high-current free-burning arcs in nitrogen[J]. J. Phys. Appl. Phys., 1993, 26D: 1224
[8] Zhang Y M, Zhang S B, Liu Y C.A plasma cloud charge sensor for pulse keyhole process control[J]. Meas. Sci. Technol., 2001, 12: 1365
[9] Fanara C.Sweeping electrostatic probes in atmospheric pressure arc plasmas——Part II: Temperature determination[J]. IEEE Trans. Plasma Sci., 2005, 33: 1082
[10] Chen S J, Jiang F, Lu Z Y, et al.Measurement and analysis of the welding arc current density and pressure distribution based on split anode method [A]. Proceedings of International Conference on Mechatronics and Automation[C]. Beijing: IEEE, 2011: 1544
[11] Schwedersky M B, Gon?alves e Silva R H, Dutra J C, et al. Two-dimensional arc stagnation pressure measurements for the double-electrode GTAW process[J]. Sci. Technol. Weld. Join., 2016, 21: 275
[12] Han Y Q, Lü Y H, Chen S J, et al.Influence of variable polarity plasma arc shape on arc force[J]. Trans. China Weld. Inst., 2005, 26(5): 49
[12] (韩永全, 吕耀辉, 陈树君等. 变极性等离子电弧形态对电弧力的影响[J]. 焊接学报, 2005, 26(5): 49)
[13] Saad E, Wang H J, Kovacevic R.Classification of molten pool modes in variable polarity plasma arc welding based on acoustic signature[J]. J. Mater. Process. Technol., 2006, 174: 127
[14] Wang Y W, Zhao P S.Noncontact acoustic analysis monitoring of plasma arc welding[J]. Int. J. Pressure Vessels Piping, 2001, 78: 43
[15] Yuan X Q, Li H, Zhao T Z, et al.Study of the characteristic of D.C. arc plasma torch[J]. Acta Phys. Sin., 2004, 53: 3806
[15] (袁行球, 李辉, 赵太泽等. 直流电弧等离子体炬的特性研究[J]. 物理学报, 2004, 53: 3806)
[16] Tian J G, Deng J, Li Y J, et al.Numerical simulation for a free-burning argon arc with MHD model[J]. Chin. J. Theor. Appl. Mech., 2011, 43: 32
[16] (田君国, 邓晶, 李要建等. 自由燃烧电弧的磁流体动力学数值模拟[J]. 力学学报, 2011, 43: 32)
[17] Shi Y, Guo C B, Huang J K, et al.Numerical simulation of pulsed current tungesten inert gas (TIG) welding arc[J]. Acta Phys. Sin., 2011, 60: 048102
[17] (石玗, 郭朝博, 黄健康等. 脉冲电流作用下TIG电弧的数值分析[J]. 物理学报, 2011, 60: 048102)
[18] Hsu K C, Etemadi K, Pfender E.Study of the free-burning high-intensity argon arc[J]. J. Appl. Phys., 1983, 54: 1293
[19] Hsu K C, Pfender E.Two-temperature modeling of the free-burning, high-intensity arc[J]. J. Appl. Phys., 1983, 54: 4359
[20] Kovitya P, Lowke J J.Two-dimensional analysis of free burning arcs in argon[J] J. Phys. Appl. Phys., 2000, 18D: 53
[21] McKelliget J, Szekely J. Heat transfer and fluid flow in the welding arc[J]. Metall. Trans., 1986, 17A: 1139
[22] Wu C S, Ushio M, Tanaka M.Analysis of the TIG welding arc behavior[J]. Comput. Mater. Sci., 1997, 7: 308
[23] Kim Y J, Lee J C.Numerical analysis of free-burning argon arcs based on the local thermodynamic equilibrium model at various electrical currents[J]. Thin Solid Films, 2013, 547: 28
[24] Lago F, Gonzalez J J, Freton P, et al.A numerical modelling of an electric arc and its interaction with the anode: part III. Application to the interaction of a lightning strike and an aircraft in flight[J]. J. Phys. Appl. Phys., 2006, 39D: 2294
[25] Blais A, Proulx P, Boulos M I.Three-dimensional numerical mode-lling of a magnetically deflected dc transferred arc in argon[J]. J. Phys. Appl. Phys., 2003, 36D: 488
[26] Xu G, Hu J, Tsai H L.Three-dimensional modeling of the plasma arc in arc welding[J]. J. Appl. Phys., 2008, 104: 103301
[27] Tanaka M, Terasaki H, Ushio M, et al.A unified numerical mode-ling of stationary tungsten-inert-gas welding process[J]. Metall. Mater. Trans., 2002, 33A: 2043
[28] Tanaka M, Terasaki H, Ushio M, et al.Numerical study of a free-burning argon arc with anode melting[J]. Plasma Chem. Plasma Process., 2003, 23: 585
[29] Tanaka M, Ushio M, Lowke J J.Numerical study of gas tungsten arc plasma with anode melting[J]. Vacuum, 2004, 73: 381
[30] Wang X X, Fan D, Huang J K, et al.A unified model of coupled arc plasma and weld pool for double electrodes TIG welding[J]. J. Phys. Appl. Phys., 2014, 47D: 275202
[31] Wang X X, Fan D, Huang J K, et al.Numerical simulation of coupled arc in double electrode tungsten inert gas welding[J]. Acta Phys. Sin., 2013, 62: 228101
[31] (王新鑫, 樊丁, 黄健康等. 双钨极耦合电弧数值模拟[J]. 物理学报, 2013, 62: 228101)
[32] Wang X X, Fan D, Huang J K, et al.Numerical simulation of heat transfer and fluid flow in double electrodes TIG arc-weld pool[J]. Acta Matall. Sin., 2015, 51: 178
[32] (王新鑫, 樊丁, 黄健康等. 双钨极TIG电弧-熔池传热与流动数值模拟[J]. 金属学报, 2015, 51: 178)
[33] Fan D, Huang Z C, Huang J K, et al.Three-dimensional numerical analysis of interaction between arc and pool by considering the behavior of the metal vapor in tungsten inert gas welding[J]. Acta Phys. Sin., 2015, 64: 108102
[33] (樊丁, 黄自成, 黄健康等. 考虑金属蒸汽的钨极惰性气体保护焊电弧与熔池交互作用三维数值分析[J]. 物理学报, 2015, 64: 108102)
[34] Lowke J J, Tanaka M.'LTE-diffusion approximation' for arc calculations[J]. J. Phys. Appl. Phys., 2006, 39D: 3634
[35] Tashiro S, Miyata M, Tanaka M.Numerical analysis of AC tungsten inert gas welding of aluminum plate in consideration of oxide layer cleaning[J]. Thin Solid Films, 2011, 519: 7025
[36] McKellige J, Szekely J, Vardelle M, et al. Temperature and velocity fields in a gas stream exiting a plasma torch. A mathematical model and its experimental verification[J]. Plasma Chem. Plasma Process., 1982, 2: 317
[37] Westhoff R, Szekely J.A model of fluid, heat flow, and electromagnetic phenomena in a nontransferred arc plasma torch[J]. J. Appl. Phys., 1991, 70: 3455
[38] Bauchire J M, Gonzalez J J, Gleizes A.Modeling of a DC plasma torch in laminar and turbulent flow[J]. Plasma Chem. Plasma Proc., 1997, 17: 409
[39] Yin F L, Hu S S, Yu C L, et al.Computational simulation for the constricted flow of argon plasma arc[J]. Comput. Mater. Sci., 2007, 40: 389
[40] Zhou Q H, Li H, Xu X, et al.Comparative study of turbulence models on highly constricted plasma cutting arc[J]. J. Phys. Appl. Phys., 2009, 42D: 015210
[41] Zhou Q H, Li H, Liu F, et al.Effects of nozzle length and process parameters on highly constricted oxygen plasma cutting arc[J]. Plasma Chem. Plasma Process., 2008, 28: 729
[42] Zhou Q H, Yin H T, Li H, et al.The effect of plasma-gas swirl flow on a highly constricted plasma cutting arc[J]. J. Phys. Appl. Phys., 2009, 42D: 095208
[43] Zhou Q H, Guo W K, Li H.Numerical simulation on the effect of shielding gas on the plasma cutting arc[J]. Acta Phys. Sin., 2011, 60: 025214
[43] (周前红, 郭文康, 李辉. 保护气对切割弧特性影响的模拟研究[J]. 物理学报, 2011, 60: 025214)
[44] Jian X X, Wu C S.Numerical analysis of the coupled arc-weld pool-keyhole behaviors in stationary plasma arc welding[J] Int. J. Heat Mass Transf., 2015, 84: 839
[45] Jian X X, Wu C S, Zhang G K, et al.A unified 3D model for an interaction mechanism of the plasma arc, weld pool and keyhole in plasma arc welding[J]. J. Phys. Appl. Phys., 2015, 48D: 465504
[1] BI Zhongnan, QIN Hailong, LIU Pei, SHI Songyi, XIE Jinli, ZHANG Ji. Research Progress Regarding Quantitative Characterization and Control Technology of Residual Stress in Superalloy Forgings[J]. 金属学报, 2023, 59(9): 1144-1158.
[2] WANG Chongyang, HAN Shiwei, XIE Feng, HU Long, DENG Dean. Influence of Solid-State Phase Transformation and Softening Effect on Welding Residual Stress of Ultra-High Strength Steel[J]. 金属学报, 2023, 59(12): 1613-1623.
[3] ZHANG Kaiyuan, DONG Wenchao, ZHAO Dong, LI Shijian, LU Shanping. Effect of Solid-State Phase Transformation on Stress and Distortion for Fe-Co-Ni Ultra-High Strength Steel Components During Welding and Vacuum Gas Quenching Processes[J]. 金属学报, 2023, 59(12): 1633-1643.
[4] XIA Dahai, DENG Chengman, CHEN Ziguang, LI Tianshu, HU Wenbin. Modeling Localized Corrosion Propagation of Metallic Materials by Peridynamics: Progresses and Challenges[J]. 金属学报, 2022, 58(9): 1093-1107.
[5] HU Long, WANG Yifeng, LI Suo, ZHANG Chaohua, DENG Dean. Study on Computational Prediction About Microstructure and Hardness of Q345 Steel Welded Joint Based on SH-CCT Diagram[J]. 金属学报, 2021, 57(8): 1073-1086.
[6] LI Zihan, XIN Jianwen, XIAO Xiao, WANG Huan, HUA Xueming, WU Dongsheng. The Arc Physical Characteristics and Molten Pool Dynamic Behaviors in Conduction Plasma Arc Welding[J]. 金属学报, 2021, 57(5): 693-702.
[7] WANG Fuqiang, LIU Wei, WANG Zhaowen. Effect of Local Cathode Current Increasing on Bath-Metal Two-Phase Flow Field in Aluminum Reduction Cells[J]. 金属学报, 2020, 56(7): 1047-1056.
[8] LIU Jizhao, HUANG Hefei, ZHU Zhenbo, LIU Awen, LI Yan. Numerical Simulation of Nanohardness in Hastelloy N Alloy After Xenon Ion Irradiation[J]. 金属学报, 2020, 56(5): 753-759.
[9] WANG Bo,SHEN Shiyi,RUAN Yanwei,CHENG Shuyong,PENG Wangjun,ZHANG Jieyu. Simulation of Gas-Liquid Two-Phase Flow in Metallurgical Process[J]. 金属学报, 2020, 56(4): 619-632.
[10] XU Qingyan,YANG Cong,YAN Xuewei,LIU Baicheng. Development of Numerical Simulation in Nickel-Based Superalloy Turbine Blade Directional Solidification[J]. 金属学报, 2019, 55(9): 1175-1184.
[11] Peiyuan DAI,Xing HU,Shijie LU,Yifeng WANG,Dean DENG. Influence of Size Factor on Calculation Accuracy of Welding Residual Stress of Stainless Steel Pipe by 2D Axisymmetric Model[J]. 金属学报, 2019, 55(8): 1058-1066.
[12] LU Shijie, WANG Hu, DAI Peiyuan, DENG Dean. Effect of Creep on Prediction Accuracy and Calculating Efficiency of Residual Stress in Post Weld Heat Treatment[J]. 金属学报, 2019, 55(12): 1581-1592.
[13] ZHANG Qingdong, LIN Xiao, LIU Jiyang, HU Shushan. Modelling of Q&P Steel Heat Treatment Process Based on Finite Element Method[J]. 金属学报, 2019, 55(12): 1569-1580.
[14] Jun LI, Mingxu XIA, Qiaodan HU, Jianguo LI. Solutions in Improving Homogeneities of Heavy Ingots[J]. 金属学报, 2018, 54(5): 773-788.
[15] Zheng LIU, Zhiping CHEN, Tao CHEN. Effects of Crucible Size and Electromagnetic Frequency on Flow During Fabrication of Semisolid A356 Al Alloy Slurry[J]. 金属学报, 2018, 54(3): 435-442.
No Suggested Reading articles found!