外加可控磁场对电阻点焊熔核组织的影响
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摘要
采用外加磁场的方法改善点焊熔核组织、提高点焊质量已为以往的研究所证实。但是,以往均采用永磁体作为磁场源,其可控性和实用性很差。本课题探讨了用电磁线圈产生可控磁场改善点焊接头组织的新方法。
为了了解外加可控磁场对点焊接头组织的影响,本文以普通低碳钢和马氏体不锈钢为研究对象,详细地分析了外加径向和横向磁场对不同钢种的电阻点焊接头结晶组织的影响。
本文首先根据电阻点焊机的实际情况设计了电磁线圈,并通过解析法和ANSYS数值模拟的方法详细计算了电磁线圈所产生的磁感应强度;为了验证计算结果的正确性,利用霍尔传感器设计了磁场测量装置,并对其进行标定,以保证所得到的磁感强度的准确性。实验测量结果与两种计算方法结果吻合良好。
其次,探讨了外加径向和横向可控磁场对点焊熔核一次结晶组织的影响,发现在正常点焊时,钢点焊熔核的凝固组织为单一的粗大柱状晶组织;在外加径向磁场作用下,与无外加磁场相比,点焊熔核组织没有明显变化。主要原因是励磁线圈所产生的径向磁感强度过小。在外加足够强度的横向磁场作用下,点焊熔核为柱状晶和等轴晶组织,晶粒更加均匀,有明显细化;并详细分析了外加横向磁场作用下熔核的结晶特点和导致组织形态变化、晶粒细化的原因。外加磁场作用使熔核中的液态金属的流动速度增大,导致合金元素的分布更加均匀。
实验结果证明,选择合适的磁场参数,外加可控磁场可改变晶粒的结晶方向,细化一次组织,提高焊缝的机械性能,是一种很有发展前景的点焊质量控制方法。
The crystallization and the quality in the nugget are improved by external controllable magnetic field in this paper. The permanent magnets was adopted as the magnetic field source in the study before, which had poor practicability and controllability. This paper discusses a new method that the crystallization be improved by controllable magnetic field produced by the electromagnetic coils.
This paper proposes a new method that controls the crystallization of spot welded joints by external controllable constant magnetic field which produced by electromagnetic coil. Taking spot weld of low carbon steel and stainless steel for example, this paper systematically analyzes the effects of external radial and transverse constant magnetic field on spot welding crystallization of low carbon steel and stainless steel.
Firstly, the electromagnetic coils are designed and produced according to practice case of the welding machine. The magnetic induction intensity is calculated by analytical method and ANSYS numerical simulation. Hall sensor is designed to measure the magnetic induction intensity. The results of three methods conform to each other very well.
Secondly, the effects of external radial and constant magnetic field on crystallization in nugget are studied. The nugget of both of steels is made up of coarse columnar crystals under general spot weld process. Comparing with the case which without external magnetic field, the microstructure has no evident change under the effect of external radial magnetic field. It is because the radial magnetic induction intensity is not strong enough. However, with the effects of external transverse constant magnetic field, the nugget is made up of refined“columnar + equiaxial”crystals, and the microstructure is more uniformly. So the reason is analyzed for which change take place. And the effects of external constant magnetic field on phase composition and microstructure are studied too. Because of the effects of external constant magnetic field, the distribution of elements is homogeneous in nugget controlled by magnetic field. The crack in the spot welded joint of stainless steel could be eliminated by external transverse constant magnetic field. So the mechanical properties of spot welded joints can improve.
It is obvious that external constant magnetic field can modify the direction of crystallization, refine grain, and improve the mechanical properties of spot welded joints. So this method has unexceptionable prospect in spot welding quality control.
为了了解外加可控磁场对点焊接头组织的影响,本文以普通低碳钢和马氏体不锈钢为研究对象,详细地分析了外加径向和横向磁场对不同钢种的电阻点焊接头结晶组织的影响。
本文首先根据电阻点焊机的实际情况设计了电磁线圈,并通过解析法和ANSYS数值模拟的方法详细计算了电磁线圈所产生的磁感应强度;为了验证计算结果的正确性,利用霍尔传感器设计了磁场测量装置,并对其进行标定,以保证所得到的磁感强度的准确性。实验测量结果与两种计算方法结果吻合良好。
其次,探讨了外加径向和横向可控磁场对点焊熔核一次结晶组织的影响,发现在正常点焊时,钢点焊熔核的凝固组织为单一的粗大柱状晶组织;在外加径向磁场作用下,与无外加磁场相比,点焊熔核组织没有明显变化。主要原因是励磁线圈所产生的径向磁感强度过小。在外加足够强度的横向磁场作用下,点焊熔核为柱状晶和等轴晶组织,晶粒更加均匀,有明显细化;并详细分析了外加横向磁场作用下熔核的结晶特点和导致组织形态变化、晶粒细化的原因。外加磁场作用使熔核中的液态金属的流动速度增大,导致合金元素的分布更加均匀。
实验结果证明,选择合适的磁场参数,外加可控磁场可改变晶粒的结晶方向,细化一次组织,提高焊缝的机械性能,是一种很有发展前景的点焊质量控制方法。
The crystallization and the quality in the nugget are improved by external controllable magnetic field in this paper. The permanent magnets was adopted as the magnetic field source in the study before, which had poor practicability and controllability. This paper discusses a new method that the crystallization be improved by controllable magnetic field produced by the electromagnetic coils.
This paper proposes a new method that controls the crystallization of spot welded joints by external controllable constant magnetic field which produced by electromagnetic coil. Taking spot weld of low carbon steel and stainless steel for example, this paper systematically analyzes the effects of external radial and transverse constant magnetic field on spot welding crystallization of low carbon steel and stainless steel.
Firstly, the electromagnetic coils are designed and produced according to practice case of the welding machine. The magnetic induction intensity is calculated by analytical method and ANSYS numerical simulation. Hall sensor is designed to measure the magnetic induction intensity. The results of three methods conform to each other very well.
Secondly, the effects of external radial and constant magnetic field on crystallization in nugget are studied. The nugget of both of steels is made up of coarse columnar crystals under general spot weld process. Comparing with the case which without external magnetic field, the microstructure has no evident change under the effect of external radial magnetic field. It is because the radial magnetic induction intensity is not strong enough. However, with the effects of external transverse constant magnetic field, the nugget is made up of refined“columnar + equiaxial”crystals, and the microstructure is more uniformly. So the reason is analyzed for which change take place. And the effects of external constant magnetic field on phase composition and microstructure are studied too. Because of the effects of external constant magnetic field, the distribution of elements is homogeneous in nugget controlled by magnetic field. The crack in the spot welded joint of stainless steel could be eliminated by external transverse constant magnetic field. So the mechanical properties of spot welded joints can improve.
It is obvious that external constant magnetic field can modify the direction of crystallization, refine grain, and improve the mechanical properties of spot welded joints. So this method has unexceptionable prospect in spot welding quality control.
引文
1李永兵,林忠钦.电阻点焊熔核形成过程磁流体动力学分析.焊接学报. 2006, 27(7): 41
2赵熹华,程亭杰.点焊熔核的孕育处理研究.焊接学报. 1995, 16(4): 244~247
3李双明.交变电磁场下金属熔体的电磁约束连续成形与凝固.材料导报. 2001, 15(3): 10
4周根树.深过冷Ni基合金在电磁场中的凝固.稀有金属材料科学与工程. 1996, 25(2): 38
5 Asai S. Birth and Resent Activities of Eletromagnetic Processing of Materials. ISIJ Int, 1989, 29(12): 981.
6 Asai S. Recent Development and Prospect of Electromagnetic Processing of Materials. Science and Technology of Advanced Materials, 2000, 1(4):191-200.
7 El-Bassyouni T A. Effect of Electromagnetic Force on Aluminum Cast Structure. Welding Journal. 1983, 33(12): 733
8刑书明.电场和磁场作用下的金属凝固.特种铸造及有色合金. 1998, (6): 37
9王建元.磁场作用下的金属凝固研究进展.材料导报. 2006, 5(20): 5
10 Charls Vives. Elaboration of Semisolid Alloys by Means of New Electromagnetic Rheocasting Processes. Metal.transB.1992, 23B:189-206.
11常云龙,杨旭.焊接磁搅拌装置的研制及其应用.焊接. 2006(5): 37
12 Tseng C F, Savage W F. The Effect of Arc Oscillation in Either the Transverse or Longitudinal Direction Has a Beneficial Effect to the Fusion Zone Microstructure and Tends to Reduce Sensitivity to Hot Cracking [J]. Welding Journal. 1971, 50(12):777-785.
13 Brown D C. The Effect of Electromagnetic Stirring and Mechanical Vibration on Arc Welding. Welding Journal. 1962, 41(2):241~250.
14 YANG Cheng-gang, GUO Xu-ming, HONG Zhang-fei. Effect of Electromagnetical Stirring on the Structure and Mechanical Properties of Weld Metal of 2219A1-Cu Alloy. Acta Metallurgica Sinica. 2005, 41(10):1071-1081
15马铁军. 12Cr17Mn9Ni4A耐蚀钢的磁控交流缝焊技术.航空制造技术. 2004, (9):70-75
16杨思乾,马铁军.多脉冲点焊与磁控制点缝焊技术及其现状.电焊机. 2005, 35(12): 36-38
17尹孝辉.外加径向恒定磁场对高强钢点焊质量的影响.哈尔滨工业大学硕士论文. 2002: 15-18
18 [苏]阿勃拉洛夫M A ,阿勃杜拉赫曼诺夫P Y著.电磁作用焊接技术.韦福水,路登平译.北京:机械工业出版社, 1988: 1-60
19 C. Brown. The Effect of Electromagnetic Stirring and Mechanical Vibration on Arc Welding. Welding Journal. 1962, 41(2): 241-250
20 C. F. Tseng, W. F. Savage. The Effect of Arc Oscillation in either the Transverse or Longitudinal Direction has a Beneficial Effect on the Fusion Zone Microstructure and Tends to Reduce Sensitivity to Hot Cracking. Welding Journal. 1971, 50(12): 777-785
21 Yu Jianrong, Zhang Jiaying. Contracted Effect of Bell-Shade Shape Welding Arc and Accompanied Magnetic Field with Spiral Pipe Shape. Transactions of Nonferrous Metals Society of China (English Edition). 1997, 7(2): 95-98
22 S. Kou, Y. Le. Improve Weld Quality by Low Frequency Arc Oscillation. Welding Journal. 1985, 64(3): 51-55
23 Malinowski-Brodnicka, W. J. Vink. Effect of Electromagnetic Stirring on GTA Welds in Austenitic Stainless Steel. Welding Journal. 1990, 69(2): 52-59
24 Liu Jinhe, Zhang Fengming. Effect of External a Magnetic Field on the Penetration of Laser Beam Welding. Proceedings of SPIE- The International Society for Optical Engineering. 1996, 2888(6-7): 364-367
25卢烨,周万盛,雅文萃.磁控电弧摆动对铝合金焊缝结晶裂纹的影响.焊接学报. 1991, 12(2): 65-71
26国旭明,钱百年,薛小怀.电磁搅拌对管线钢埋弧焊熔敷金属低温韧性的影响.金属学报. 2000, 36(2): 177-180
27 H. C. Tse, H. C. Man, T. M. Yue. Effect of Electric and Magnetic Fields on Plasma Control during CO2 Laser Welding. Optics and Lasers in Engineering. 1999, 32(1): 55-63
28 H. C. Tse, H. C. Man, T. M. Yue. Effect of Magnetic Field on Plasma Controlduring CO2 Laser Welding. Optics and Laser Technology. 1999, 31(5): 363-368
29 J. C. Villafuerte, H. W. Kerr. Electromagnetic Stirring and Grain Refinement in Stainless Steel GTA Welds. Welding Journal. 1990, 69(1): 1-13
30 S. Kou, Y. Le. Nucleation Mechanical and Grain Refining of Weld Metal. Welding Journal. 1986, 65(12): 305-313
31 F. Tang, A. L. Lu. Research on Residual Stress Reduction by a Low Frequency Alternating Magnetic Field. Journal of Materials Processing Technology. 1998, 74(2): 255-258
32 S. Asai. Recent Development and Prospect of Electromagnetic Processing of Materials. Science and Technology of Advanced Materials. 2000, 1(4): 191-200
33常云龙,贺优优,杜怀周,等.纵向磁场对低碳钢MIG焊焊缝组织及性能的影响.沈阳工业大学学报. 2007, 29(4): 387
34魏国. CO2气体保护焊飞溅产生的原因及减少措施.机械工人热加工. 2006, (6): 47-48
35陈埒涛.外加纵向磁场对CO2焊短路过渡飞溅影响的研究.电焊机. 2005,
35(4): 34
36杨成刚,国旭明,洪张飞,等.电磁搅拌对2219AL-Cu合金焊缝组织及力学性能的影响.金属学报. 2005, 41(10):1081
37贾昌申,罗键.外加间歇交变纵向磁场对GTAW焊缝中气孔的抑制.航空工艺技术. 1999, 42(3): 26-28
38汤光平,陈金明.电磁搅拌技术在焊接中的应用.焊接技术. 2006, 35(5): 3-4
39 Primo Podraj, Ivan Polajnar. Expulsion Detection System for Resistance Spot Welding Based on a Neural Network. Measurement Science and Technology. 2004, 15(5):592-598
40 Wu P, Zhang W, Bay N. Characterization of Dynamic Mechanical Properties of Resistance Welding Machines. Welding Journal. 2005, 84(1):17-21
41武佩,马彦华.电阻点焊电磁力的试验分析.焊接学报. 2006, 27(10): 4-6
42张三慧.电磁学.清华大学出版社. 1999: 245-249
43周昌玉,贺小华.有限元分析的基本方法及工程应用.化学工业出版社. 2006:103-121.
44雷银照.轴对称线圈磁场计算.中国计量出版社. 1991: 4-99
45蒋大林,高工. AD22151线性输出磁场传感器的原理及应用.电子技术应用. 1999(5): 70-72
46野笃美.金属凝固学.唐彦斌,张正德译.机械工业出版社, 1983: 50-71
47赵熹华,姜以宏.薄件点焊熔核凝固组织分析.焊接学报. 1994, 15(2): 89-93
48吉林工业大学.焊接冶金与金属焊接性.吉林大学出版社. 1980: 100
2赵熹华,程亭杰.点焊熔核的孕育处理研究.焊接学报. 1995, 16(4): 244~247
3李双明.交变电磁场下金属熔体的电磁约束连续成形与凝固.材料导报. 2001, 15(3): 10
4周根树.深过冷Ni基合金在电磁场中的凝固.稀有金属材料科学与工程. 1996, 25(2): 38
5 Asai S. Birth and Resent Activities of Eletromagnetic Processing of Materials. ISIJ Int, 1989, 29(12): 981.
6 Asai S. Recent Development and Prospect of Electromagnetic Processing of Materials. Science and Technology of Advanced Materials, 2000, 1(4):191-200.
7 El-Bassyouni T A. Effect of Electromagnetic Force on Aluminum Cast Structure. Welding Journal. 1983, 33(12): 733
8刑书明.电场和磁场作用下的金属凝固.特种铸造及有色合金. 1998, (6): 37
9王建元.磁场作用下的金属凝固研究进展.材料导报. 2006, 5(20): 5
10 Charls Vives. Elaboration of Semisolid Alloys by Means of New Electromagnetic Rheocasting Processes. Metal.transB.1992, 23B:189-206.
11常云龙,杨旭.焊接磁搅拌装置的研制及其应用.焊接. 2006(5): 37
12 Tseng C F, Savage W F. The Effect of Arc Oscillation in Either the Transverse or Longitudinal Direction Has a Beneficial Effect to the Fusion Zone Microstructure and Tends to Reduce Sensitivity to Hot Cracking [J]. Welding Journal. 1971, 50(12):777-785.
13 Brown D C. The Effect of Electromagnetic Stirring and Mechanical Vibration on Arc Welding. Welding Journal. 1962, 41(2):241~250.
14 YANG Cheng-gang, GUO Xu-ming, HONG Zhang-fei. Effect of Electromagnetical Stirring on the Structure and Mechanical Properties of Weld Metal of 2219A1-Cu Alloy. Acta Metallurgica Sinica. 2005, 41(10):1071-1081
15马铁军. 12Cr17Mn9Ni4A耐蚀钢的磁控交流缝焊技术.航空制造技术. 2004, (9):70-75
16杨思乾,马铁军.多脉冲点焊与磁控制点缝焊技术及其现状.电焊机. 2005, 35(12): 36-38
17尹孝辉.外加径向恒定磁场对高强钢点焊质量的影响.哈尔滨工业大学硕士论文. 2002: 15-18
18 [苏]阿勃拉洛夫M A ,阿勃杜拉赫曼诺夫P Y著.电磁作用焊接技术.韦福水,路登平译.北京:机械工业出版社, 1988: 1-60
19 C. Brown. The Effect of Electromagnetic Stirring and Mechanical Vibration on Arc Welding. Welding Journal. 1962, 41(2): 241-250
20 C. F. Tseng, W. F. Savage. The Effect of Arc Oscillation in either the Transverse or Longitudinal Direction has a Beneficial Effect on the Fusion Zone Microstructure and Tends to Reduce Sensitivity to Hot Cracking. Welding Journal. 1971, 50(12): 777-785
21 Yu Jianrong, Zhang Jiaying. Contracted Effect of Bell-Shade Shape Welding Arc and Accompanied Magnetic Field with Spiral Pipe Shape. Transactions of Nonferrous Metals Society of China (English Edition). 1997, 7(2): 95-98
22 S. Kou, Y. Le. Improve Weld Quality by Low Frequency Arc Oscillation. Welding Journal. 1985, 64(3): 51-55
23 Malinowski-Brodnicka, W. J. Vink. Effect of Electromagnetic Stirring on GTA Welds in Austenitic Stainless Steel. Welding Journal. 1990, 69(2): 52-59
24 Liu Jinhe, Zhang Fengming. Effect of External a Magnetic Field on the Penetration of Laser Beam Welding. Proceedings of SPIE- The International Society for Optical Engineering. 1996, 2888(6-7): 364-367
25卢烨,周万盛,雅文萃.磁控电弧摆动对铝合金焊缝结晶裂纹的影响.焊接学报. 1991, 12(2): 65-71
26国旭明,钱百年,薛小怀.电磁搅拌对管线钢埋弧焊熔敷金属低温韧性的影响.金属学报. 2000, 36(2): 177-180
27 H. C. Tse, H. C. Man, T. M. Yue. Effect of Electric and Magnetic Fields on Plasma Control during CO2 Laser Welding. Optics and Lasers in Engineering. 1999, 32(1): 55-63
28 H. C. Tse, H. C. Man, T. M. Yue. Effect of Magnetic Field on Plasma Controlduring CO2 Laser Welding. Optics and Laser Technology. 1999, 31(5): 363-368
29 J. C. Villafuerte, H. W. Kerr. Electromagnetic Stirring and Grain Refinement in Stainless Steel GTA Welds. Welding Journal. 1990, 69(1): 1-13
30 S. Kou, Y. Le. Nucleation Mechanical and Grain Refining of Weld Metal. Welding Journal. 1986, 65(12): 305-313
31 F. Tang, A. L. Lu. Research on Residual Stress Reduction by a Low Frequency Alternating Magnetic Field. Journal of Materials Processing Technology. 1998, 74(2): 255-258
32 S. Asai. Recent Development and Prospect of Electromagnetic Processing of Materials. Science and Technology of Advanced Materials. 2000, 1(4): 191-200
33常云龙,贺优优,杜怀周,等.纵向磁场对低碳钢MIG焊焊缝组织及性能的影响.沈阳工业大学学报. 2007, 29(4): 387
34魏国. CO2气体保护焊飞溅产生的原因及减少措施.机械工人热加工. 2006, (6): 47-48
35陈埒涛.外加纵向磁场对CO2焊短路过渡飞溅影响的研究.电焊机. 2005,
35(4): 34
36杨成刚,国旭明,洪张飞,等.电磁搅拌对2219AL-Cu合金焊缝组织及力学性能的影响.金属学报. 2005, 41(10):1081
37贾昌申,罗键.外加间歇交变纵向磁场对GTAW焊缝中气孔的抑制.航空工艺技术. 1999, 42(3): 26-28
38汤光平,陈金明.电磁搅拌技术在焊接中的应用.焊接技术. 2006, 35(5): 3-4
39 Primo Podraj, Ivan Polajnar. Expulsion Detection System for Resistance Spot Welding Based on a Neural Network. Measurement Science and Technology. 2004, 15(5):592-598
40 Wu P, Zhang W, Bay N. Characterization of Dynamic Mechanical Properties of Resistance Welding Machines. Welding Journal. 2005, 84(1):17-21
41武佩,马彦华.电阻点焊电磁力的试验分析.焊接学报. 2006, 27(10): 4-6
42张三慧.电磁学.清华大学出版社. 1999: 245-249
43周昌玉,贺小华.有限元分析的基本方法及工程应用.化学工业出版社. 2006:103-121.
44雷银照.轴对称线圈磁场计算.中国计量出版社. 1991: 4-99
45蒋大林,高工. AD22151线性输出磁场传感器的原理及应用.电子技术应用. 1999(5): 70-72
46野笃美.金属凝固学.唐彦斌,张正德译.机械工业出版社, 1983: 50-71
47赵熹华,姜以宏.薄件点焊熔核凝固组织分析.焊接学报. 1994, 15(2): 89-93
48吉林工业大学.焊接冶金与金属焊接性.吉林大学出版社. 1980: 100