基于光电信息的激光焊接等离子体研究
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摘要
激光焊接作为新型焊接技术,以其能量密度高、焊接热输入小、焊速高等优点日益受到重视。在激光焊接过程中,随着激光能量的增大,会产生激光焊接等离子体,它对焊接过程有着重要影响,甚至能够决定焊接的成功与否。因此,对激光焊接等离子体的检测研究具有重要意义;研究等离子体性质和内部作用机制,有助于深入理解激光焊接作用机理,改进激光焊接工艺。
等离子体的诊断与检测主要有声、光、电及光谱方面的方法,其中光谱和高速摄像等宏观研究方法使用较多,而电信号应用较少。国内外研究多采用单一检测方法,各信息结果孤立;而激光焊接等离子体波动变化剧烈,这就需要在较高时间分辨率下进行研究;对实时条件下激光等离子体波动现象的光谱诊断研究也尚不多见。
为此,本文自主设计了光谱信号、电信号以及高速摄像同步采集系统,对相同时刻下的激光焊接等离子体进行多维信息采集。通过分析等离子体特征参数以及波动特征,来研究激光焊接等离子体的能量与物质传输规律。
对激光焊接等离子体采集到的同步信号进行分析后,可以得出:光电采集系统能够全面获取等离子体特征信息,各信号参数特征明显,其变化规律与等离子体波动规律一致,可以全面表征等离子体特征及变化规律。
采用方波脉冲激光进行焊接实验,发现等离子体波动现象有两种表现形式。采集到的多维信号能够解释等离子体的波动性现象,且符合相关理论。对采用活性剂的激光焊接研究后发现,复合信号特征能很好的对应活性剂作用机理。
本文设计的多信息复合采集系统,可以对激光焊接等离子体进行多维信息分析,具有很好的实用性,为研究激光焊接本质提供了有效的方法。
Laser welding, as a new welding technology, is becoming highly valued. Laser welding has many advantages such as high energy density, small heat affected zone, high welding speed. In the welding process, plasma will be generated with more laser energy. It has an important impact on the welding process and even determines the success of welding. Therefore, the study of laser welding plasma is of great significance. The research of plasma properties and internal mechanism contributed to a better understanding of the mechanism of laser welding and the improvement of laser welding process.
The plasma diagnostics involve many methods, such as sound, light, electricity and spectral method. The spectral method and high-speed photograph are widely used, while the method of electric signal is seldom used. The domestic and international researches always adopt single detection method, research results are isolated. It requires a higher time resolution study that the laser welding plasma changes dramatically. There are few spectral investigations about wave phenomena of laser welding in real time.
Therefore, this thesis firstly designs a new data synchronous acquisition about spectrum signal, electric signal and high-speed photograph. This acquisition could collect multi-dimensional information of laser welding plasma at the same time. The paper studies propagation law of matter and energy in laser welding plasma, through analyzing the characteristics of the parameters and wave characteristics of plasma.
Results obtained from the study of multi-dimensional information are as follows: The optical and electrical synchronous acquisition system is able to obtain the whole feature information of plasma. The features of signals are characteristic and their changing rule is accorded with the variation law of plasma. The hybrid signals could fully characterize the variation of plasma.
In the experiment of squarewave pulse laser, two forms of wave phenomenon are found. Multi-dimensional signals can explain the volatility of plasma, and are in accordance with relevant theory. In the laser welding with activating flux, the features of hybrid signals correspond with the mechanism of activating flux.
The optical and electrical synchronous acquisition system could analysis the multi-dimensional information of laser welding plasma. It is practical with satisfactory results and provides a new way to research the laser welding deeply.
等离子体的诊断与检测主要有声、光、电及光谱方面的方法,其中光谱和高速摄像等宏观研究方法使用较多,而电信号应用较少。国内外研究多采用单一检测方法,各信息结果孤立;而激光焊接等离子体波动变化剧烈,这就需要在较高时间分辨率下进行研究;对实时条件下激光等离子体波动现象的光谱诊断研究也尚不多见。
为此,本文自主设计了光谱信号、电信号以及高速摄像同步采集系统,对相同时刻下的激光焊接等离子体进行多维信息采集。通过分析等离子体特征参数以及波动特征,来研究激光焊接等离子体的能量与物质传输规律。
对激光焊接等离子体采集到的同步信号进行分析后,可以得出:光电采集系统能够全面获取等离子体特征信息,各信号参数特征明显,其变化规律与等离子体波动规律一致,可以全面表征等离子体特征及变化规律。
采用方波脉冲激光进行焊接实验,发现等离子体波动现象有两种表现形式。采集到的多维信号能够解释等离子体的波动性现象,且符合相关理论。对采用活性剂的激光焊接研究后发现,复合信号特征能很好的对应活性剂作用机理。
本文设计的多信息复合采集系统,可以对激光焊接等离子体进行多维信息分析,具有很好的实用性,为研究激光焊接本质提供了有效的方法。
Laser welding, as a new welding technology, is becoming highly valued. Laser welding has many advantages such as high energy density, small heat affected zone, high welding speed. In the welding process, plasma will be generated with more laser energy. It has an important impact on the welding process and even determines the success of welding. Therefore, the study of laser welding plasma is of great significance. The research of plasma properties and internal mechanism contributed to a better understanding of the mechanism of laser welding and the improvement of laser welding process.
The plasma diagnostics involve many methods, such as sound, light, electricity and spectral method. The spectral method and high-speed photograph are widely used, while the method of electric signal is seldom used. The domestic and international researches always adopt single detection method, research results are isolated. It requires a higher time resolution study that the laser welding plasma changes dramatically. There are few spectral investigations about wave phenomena of laser welding in real time.
Therefore, this thesis firstly designs a new data synchronous acquisition about spectrum signal, electric signal and high-speed photograph. This acquisition could collect multi-dimensional information of laser welding plasma at the same time. The paper studies propagation law of matter and energy in laser welding plasma, through analyzing the characteristics of the parameters and wave characteristics of plasma.
Results obtained from the study of multi-dimensional information are as follows: The optical and electrical synchronous acquisition system is able to obtain the whole feature information of plasma. The features of signals are characteristic and their changing rule is accorded with the variation law of plasma. The hybrid signals could fully characterize the variation of plasma.
In the experiment of squarewave pulse laser, two forms of wave phenomenon are found. Multi-dimensional signals can explain the volatility of plasma, and are in accordance with relevant theory. In the laser welding with activating flux, the features of hybrid signals correspond with the mechanism of activating flux.
The optical and electrical synchronous acquisition system could analysis the multi-dimensional information of laser welding plasma. It is practical with satisfactory results and provides a new way to research the laser welding deeply.
引文
[1]肖荣诗,陈铠,陈继民等.CO2激光焊接光致等离子体屏蔽机制的实验研究[J].激光技术,2001,25 (3):238~241.
[2]潘际銮,郑军,屈岳波.激光焊技术的发展[J].焊接,2009(2):18~21.
[3]李力钧.现代激光加工及其装备[M].北京:北京理工大学出版社,1993.
[4]王家金.激光加工技术[M].北京:中国计量出版社,1992.
[5]张永康.激光加工技术[M].北京:化学工业出版社,2004.
[6]刘金合.高能密度焊[M].西安:西北工业大学出版社,1995.
[7]肖荣诗,陈涛,陈铠等.低碳CO2激光焊接光致等离子体屏蔽的实验研究[J].应用激光,1999,19(2):49~51.
[8] Wernecke S.J. Maximum entropy image reconstruction[J]. IEEE Trans Computer, 1977, C-26:351~364.
[9]肖荣诗,陈铠,陈继民等.CO2激光焊接光致等离子体屏蔽机制的实验研究[J].激光技术,2001,25(3):238~241.
[10]刘金合,张锋铭等.CO2激光焊接产生的等离子体对光束的影响分析[C].宜昌:第六届电子束、离子束学术年会,1995.
[11]陆建,倪晓武,贺安之.激光与材料相互作用物理学[M].北京:机械工业出版社,1996.
[12]张锋铭.大功率CO2激光焊接过程中产生的等离子体对激光传输影响的研究[D].西安:西北工业大学,1998.
[13]刘金合,朱石刚.CO2激光焊接等离子体高速摄影照片图像处理[J].应用激光,2002,22(3):342~344.
[14] A J H Donne.等离子体诊断介绍(火花译)[M].万方数据库,67~72.
[15]王建平.激光焊接等离子体三维图像重建的计算机模拟研究[D].西安:西安交通大学,2001.
[16] Giovanni Tani,Luca Tomesani,Giampaolo Campana.Evaluation of molten pool geometry with induced plasma plume absorption in laser-material interaction zone[J]. International Journal of Machine Tools and Manufacture.2007,47(5):971~977.
[17]段爱琴,陈俐,王亚军.CO2激光焊接不锈钢光致等离子体动态特性分析[J].焊接学报,2005,26(11):17~20.
[18]骆红,胡伦骥,黄树槐等.激光焊接中的等离子体振荡[J].应用激光, 1997,17(2):77~78.
[19] Griem H R. Plasma Spectroscopy [M]. New York:McGraw-Hill,1964.
[20] Lochte-Holtgreven, W. Plasma Diagnostics[M]. Amsterdam:North-Holland Publishing Co., 1968.
[21] Michele Ferrara, Antonio Ancona, Pietro Mario L.et al. On-line quality monitoring of welding processes by means of plasma optical spectroscopy[J]. Proceedings of SPIE,2000,3888(2000):750~758.
[22] T.Sibillano, A.Ancona, V.Berardi et al. Real-time monitoring of laser welding by correlation analysis: The case of AA5083[J].Optics and Laser in Engineering, 2007,45(2007):1005~1009.
[23]唐霞辉,朱海红,朱国富等.高功率激光焊接光致等离子体的检测[J].激光技术,1996,20(5):312~316.
[24]苏彦东.大功率激光焊接光致等离子体的光谱分析[J].中国机械工程,2000,11(12):1389~1392.
[25]祁俊峰,丁鹏,张冬云等.工艺参数对铝合金CO2激光焊接光致等离子体温度的影响[J].焊接学报,2008,29(6):97~100.
[26] Liming Liu, Ruisheng Huang, Gang Song. Behavior and Spectrum Analysis of Welding Arc in Low-Power YAG-Laser-MAG Hybrid-welding Process[J]. IEEE Transactions on Plasma Science,2008,36(4):1937~1943.
[27]刘黎明,黄瑞生,曹运明.低功率YAG激光-熔化极气体弧焊复合焊接电弧等离子体行为研究[J].中国激光,2009,36(12):3167~3173.
[28] T. Sibillano, A. Ancona et al. Correlation analysis in laser welding plasma[J]. Optics Communications, 2005, 251(1):139-148.
[29]张屹,李力钧.激光深熔焊接小孔效应的传热性研究[J].中国激光, 2004,31(12):1538~1542.
[30]张屹,陈根余,李力钧.基于实测小孔的激光深熔焊接三维传热模型[J].焊接学报,2008,29(2):27~30.
[31]张屹.基于“三明治”新方法的激光深熔焊接小孔效应的模拟研究[D].长沙:湖南大学,2005.
[32] Grill A. Cold plasma in materials fabrication: from fundamentals to applications[J]. New York: IEEE Press, 1994.
[33]许根慧,姜恩永,盛京等.等离子体技术与应用[M].北京:化学工业出版社, 2006.
[34]郝新锋.低功率YAG激光+TIG复合热源焊接技术研究[D].大连:大连理工大学,2010.
[35]杨运强,李俊岳,李桓等.发展中的焊接电弧光谱测控技术[J].焊接, 2001(6):11~15.
[36]杨运强,宋永伦,李俊岳.铝焊接电弧物理特性的研究[J].湘潭大学自然科学学报,1995,17(4):107~110.
[37]卢亚静,胡绳荪,单平等.等离子鞘层在等离子弧焊中的应用[J].天津大学学报,36(5):562~566.
[38] C. Ursu, S. Gurlui, C. Focsa. ea tl. Space-and time-resolved optical diagnosis for the study of laser ablation plasma dynamics [J].Nuclear Instruments and Methods in Physics Research B, 2009(267):446~450.
[39]柳刚.熔化极气体保护焊熔滴过渡的光谱信息及其检测的研究[D].天津:天津大学,1998.
[40]辛仁轩等.离子体发射光谱分析[M].北京:化学工业出版社,2004,12~42.
[41]过增元,赵文华.电弧和热等离子体[M].北京:科学出版社,1986,296~302.
[42]傅育文,胡绳荪,易小林等.等离子云信号检测与影响因素分析[J].焊接学报, 2003,24(5):29~32.
[43] Bittencourt J A. Fundamentals of Plasma Physics[M]. New York: Pergamon Press, 1986.
[44]杨璟.铝合金激光深熔焊接过程行为与缺陷控制研究[D].北京:北京工业大学,2011.
[45] Jun Wang, Chunming Wang, Xuanxuan Meng ea tl. Study on the periodic oscillation of plasma/vapour induced during high power fibre laser penetration welding [J].Optics & Laser Technology, 2012(44):67~70.
[46]樊艳峰,刘金合,罗晓娜等.活性剂对低功率脉冲激光焊接不锈钢的影响[J].金属铸锻焊技术,2008,37(23):77~80.
[47] Kuo M,Sun Z,Pan D, Laser welding with activating flux[J].Science and Technology of Welding and Joining, 2001, 6(1):17~22.
[48] Heiple C R,Roper J R,Mechanism for minior element effect on TIG fusion zone geometry[J].Welding Joutnal, 1982, 61(4):97~102.
[2]潘际銮,郑军,屈岳波.激光焊技术的发展[J].焊接,2009(2):18~21.
[3]李力钧.现代激光加工及其装备[M].北京:北京理工大学出版社,1993.
[4]王家金.激光加工技术[M].北京:中国计量出版社,1992.
[5]张永康.激光加工技术[M].北京:化学工业出版社,2004.
[6]刘金合.高能密度焊[M].西安:西北工业大学出版社,1995.
[7]肖荣诗,陈涛,陈铠等.低碳CO2激光焊接光致等离子体屏蔽的实验研究[J].应用激光,1999,19(2):49~51.
[8] Wernecke S.J. Maximum entropy image reconstruction[J]. IEEE Trans Computer, 1977, C-26:351~364.
[9]肖荣诗,陈铠,陈继民等.CO2激光焊接光致等离子体屏蔽机制的实验研究[J].激光技术,2001,25(3):238~241.
[10]刘金合,张锋铭等.CO2激光焊接产生的等离子体对光束的影响分析[C].宜昌:第六届电子束、离子束学术年会,1995.
[11]陆建,倪晓武,贺安之.激光与材料相互作用物理学[M].北京:机械工业出版社,1996.
[12]张锋铭.大功率CO2激光焊接过程中产生的等离子体对激光传输影响的研究[D].西安:西北工业大学,1998.
[13]刘金合,朱石刚.CO2激光焊接等离子体高速摄影照片图像处理[J].应用激光,2002,22(3):342~344.
[14] A J H Donne.等离子体诊断介绍(火花译)[M].万方数据库,67~72.
[15]王建平.激光焊接等离子体三维图像重建的计算机模拟研究[D].西安:西安交通大学,2001.
[16] Giovanni Tani,Luca Tomesani,Giampaolo Campana.Evaluation of molten pool geometry with induced plasma plume absorption in laser-material interaction zone[J]. International Journal of Machine Tools and Manufacture.2007,47(5):971~977.
[17]段爱琴,陈俐,王亚军.CO2激光焊接不锈钢光致等离子体动态特性分析[J].焊接学报,2005,26(11):17~20.
[18]骆红,胡伦骥,黄树槐等.激光焊接中的等离子体振荡[J].应用激光, 1997,17(2):77~78.
[19] Griem H R. Plasma Spectroscopy [M]. New York:McGraw-Hill,1964.
[20] Lochte-Holtgreven, W. Plasma Diagnostics[M]. Amsterdam:North-Holland Publishing Co., 1968.
[21] Michele Ferrara, Antonio Ancona, Pietro Mario L.et al. On-line quality monitoring of welding processes by means of plasma optical spectroscopy[J]. Proceedings of SPIE,2000,3888(2000):750~758.
[22] T.Sibillano, A.Ancona, V.Berardi et al. Real-time monitoring of laser welding by correlation analysis: The case of AA5083[J].Optics and Laser in Engineering, 2007,45(2007):1005~1009.
[23]唐霞辉,朱海红,朱国富等.高功率激光焊接光致等离子体的检测[J].激光技术,1996,20(5):312~316.
[24]苏彦东.大功率激光焊接光致等离子体的光谱分析[J].中国机械工程,2000,11(12):1389~1392.
[25]祁俊峰,丁鹏,张冬云等.工艺参数对铝合金CO2激光焊接光致等离子体温度的影响[J].焊接学报,2008,29(6):97~100.
[26] Liming Liu, Ruisheng Huang, Gang Song. Behavior and Spectrum Analysis of Welding Arc in Low-Power YAG-Laser-MAG Hybrid-welding Process[J]. IEEE Transactions on Plasma Science,2008,36(4):1937~1943.
[27]刘黎明,黄瑞生,曹运明.低功率YAG激光-熔化极气体弧焊复合焊接电弧等离子体行为研究[J].中国激光,2009,36(12):3167~3173.
[28] T. Sibillano, A. Ancona et al. Correlation analysis in laser welding plasma[J]. Optics Communications, 2005, 251(1):139-148.
[29]张屹,李力钧.激光深熔焊接小孔效应的传热性研究[J].中国激光, 2004,31(12):1538~1542.
[30]张屹,陈根余,李力钧.基于实测小孔的激光深熔焊接三维传热模型[J].焊接学报,2008,29(2):27~30.
[31]张屹.基于“三明治”新方法的激光深熔焊接小孔效应的模拟研究[D].长沙:湖南大学,2005.
[32] Grill A. Cold plasma in materials fabrication: from fundamentals to applications[J]. New York: IEEE Press, 1994.
[33]许根慧,姜恩永,盛京等.等离子体技术与应用[M].北京:化学工业出版社, 2006.
[34]郝新锋.低功率YAG激光+TIG复合热源焊接技术研究[D].大连:大连理工大学,2010.
[35]杨运强,李俊岳,李桓等.发展中的焊接电弧光谱测控技术[J].焊接, 2001(6):11~15.
[36]杨运强,宋永伦,李俊岳.铝焊接电弧物理特性的研究[J].湘潭大学自然科学学报,1995,17(4):107~110.
[37]卢亚静,胡绳荪,单平等.等离子鞘层在等离子弧焊中的应用[J].天津大学学报,36(5):562~566.
[38] C. Ursu, S. Gurlui, C. Focsa. ea tl. Space-and time-resolved optical diagnosis for the study of laser ablation plasma dynamics [J].Nuclear Instruments and Methods in Physics Research B, 2009(267):446~450.
[39]柳刚.熔化极气体保护焊熔滴过渡的光谱信息及其检测的研究[D].天津:天津大学,1998.
[40]辛仁轩等.离子体发射光谱分析[M].北京:化学工业出版社,2004,12~42.
[41]过增元,赵文华.电弧和热等离子体[M].北京:科学出版社,1986,296~302.
[42]傅育文,胡绳荪,易小林等.等离子云信号检测与影响因素分析[J].焊接学报, 2003,24(5):29~32.
[43] Bittencourt J A. Fundamentals of Plasma Physics[M]. New York: Pergamon Press, 1986.
[44]杨璟.铝合金激光深熔焊接过程行为与缺陷控制研究[D].北京:北京工业大学,2011.
[45] Jun Wang, Chunming Wang, Xuanxuan Meng ea tl. Study on the periodic oscillation of plasma/vapour induced during high power fibre laser penetration welding [J].Optics & Laser Technology, 2012(44):67~70.
[46]樊艳峰,刘金合,罗晓娜等.活性剂对低功率脉冲激光焊接不锈钢的影响[J].金属铸锻焊技术,2008,37(23):77~80.
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