TC4钛合金扫描电子束焊接温度场数值模拟
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摘要
建立了TC4钛合金扫描电子束焊接三维温度场的数学模型.采用电子束光斑半径较大的焊接工艺,开展了椭圆扫描/无扫描电子束焊接的试验和数值模拟研究.模拟结果与试验结果吻合良好.结果表明,电子束扫描可使高温熔池的深度减小、宽度增加、提前进入稳态,并且显著降低熔池最高温度和冷却速度.对加速电压为60 kV、电子束流为10 mA、焊接速度为0.9 m/min的电子束焊接工艺,频率为500 Hz的电子束椭圆扫描可使熔池最高温度降低近1 900 K、冷却速度每秒降低近100 K.
A three dimension mathematical model was proposed to calculate the temperature field during scanning electron beam welding.Adopting reasonable welding technology to obtain the large spot radius of electron beam,the simulations and experiments on scanning/normal electron beam welding of TC4 titanium alloy were carried out.The simulated results agree well with that of experiments.The research shows that electron beam scanning can increase the weld pool width,decrease the weld pool depth,make the weld pool being steady state earlier,and obviously decrease the maximum temperature and the cooling rate of the weld pool.For the electron beam welding process(U=60 kV,Ib=100 mA,V=0.9 m/min) with a 500 Hz ellipsoid beam scanning,the maximum temperature of weld pool can decrease by 1 900 K and the cooling rate decreases by 100 K/s.
A three dimension mathematical model was proposed to calculate the temperature field during scanning electron beam welding.Adopting reasonable welding technology to obtain the large spot radius of electron beam,the simulations and experiments on scanning/normal electron beam welding of TC4 titanium alloy were carried out.The simulated results agree well with that of experiments.The research shows that electron beam scanning can increase the weld pool width,decrease the weld pool depth,make the weld pool being steady state earlier,and obviously decrease the maximum temperature and the cooling rate of the weld pool.For the electron beam welding process(U=60 kV,Ib=100 mA,V=0.9 m/min) with a 500 Hz ellipsoid beam scanning,the maximum temperature of weld pool can decrease by 1 900 K and the cooling rate decreases by 100 K/s.
引文
[1]张喜燕,赵永庆,白晨光.钛合金及应用[M].北京:化学工业出版社,2005.
[2]Mayer R,Dietrich W,Sundermeyer D.New high-speed beamcurrent control and deflection systems improve electron beamwelding applications[J].Welding Journal,1977,56(6):35-41.
[3]Matsuda F,Nakagawa H,Nakata K,et al.Effect of electronmagnetic stirring on weld solidification structure of aluminum al-loys[J].Welding of Light Metals,1978,16(1):8-20.
[4]赵晖,韩忠,陈晓风.电子束扫描对Ti-6Al-4V合金焊缝金属组织的影响[J].焊接学报,2005,26(1):78-80.Zhao Hui,Han Zhong,Chen Xiaofeng.Effect of scanning elec-tron beam on solidified structure of welded Ti-6Al-4V alloy[J].Transactions of the China Welding Institution,2005,26(1):78-80;
[5]Wang S,Wu X.Investigation on the microstructure and mechani-cal properties of Ti-6Al-4V alloy joints with electron beam weld-ing[J].Materials and Design,2012,36:663-670.
[6]Wei P S,Ho C Y,Shian M D,et al.Three-dimensional analyti-cal temperature field and its application to solidification character-istics in high or lowpowerdensitybeam welding[J].InternationalJournal of Heat and Mass Transfer,1997,40(10):2283-2292.
[7]Couedel D,Rogeon P,Lemasson P,et al.2D-heat transfer mod-eling within limited regions using moving sources:application toelectron beam welding[J].International Journal of Heat andMass Transfer,2003,46(23):4553-4559.
[8]Rai R,Palmer T A,Elmer J W,et al.Heat transfer and fluidflow during electron beam welding of 304L stainless steel alloy[J].Welding Journal,2009,88(3):54-61.
[9]王煜,赵海燕,吴甦,等.电子束焊接数值模拟中分段移动双椭球热源模型的建立[J].机械工程学报,2004,40(2):165-169.Wang Yu,Zhao Haiyan,Wu Su,et al.Establishment of seg-mented moving double ellipsoid heat source model in electronbeam welding numerical simulation[J].Chinese Journal of Me-chanical Engineering,2004,40(2):165-169.
[10]王西昌,吴冰,左从进,等.电子束焊接数值模拟新型热源模型的初步探索[J].焊接学报,2005,26(12):81-84.Wang Xichang,Wu Bing,Zuo Congjin,et al.New heat sourcemodel for numetical simulation of electron beam welding[J].Transactions of the China Welding Institution,2005,26(12):81-84.
[11]罗怡,许惠斌,李春天,等.真空电子束焊接热源建模及功率密度分析[J].焊接学报,2010,31(9):73-76.Luo Yi,Xu Huibin,Li Chuntian,et al.Heat source modelingand power density analysis for vacuum electron beam welding[J].Transactions of the China Welding Institution,2010,31(9):73-76.
[2]Mayer R,Dietrich W,Sundermeyer D.New high-speed beamcurrent control and deflection systems improve electron beamwelding applications[J].Welding Journal,1977,56(6):35-41.
[3]Matsuda F,Nakagawa H,Nakata K,et al.Effect of electronmagnetic stirring on weld solidification structure of aluminum al-loys[J].Welding of Light Metals,1978,16(1):8-20.
[4]赵晖,韩忠,陈晓风.电子束扫描对Ti-6Al-4V合金焊缝金属组织的影响[J].焊接学报,2005,26(1):78-80.Zhao Hui,Han Zhong,Chen Xiaofeng.Effect of scanning elec-tron beam on solidified structure of welded Ti-6Al-4V alloy[J].Transactions of the China Welding Institution,2005,26(1):78-80;
[5]Wang S,Wu X.Investigation on the microstructure and mechani-cal properties of Ti-6Al-4V alloy joints with electron beam weld-ing[J].Materials and Design,2012,36:663-670.
[6]Wei P S,Ho C Y,Shian M D,et al.Three-dimensional analyti-cal temperature field and its application to solidification character-istics in high or lowpowerdensitybeam welding[J].InternationalJournal of Heat and Mass Transfer,1997,40(10):2283-2292.
[7]Couedel D,Rogeon P,Lemasson P,et al.2D-heat transfer mod-eling within limited regions using moving sources:application toelectron beam welding[J].International Journal of Heat andMass Transfer,2003,46(23):4553-4559.
[8]Rai R,Palmer T A,Elmer J W,et al.Heat transfer and fluidflow during electron beam welding of 304L stainless steel alloy[J].Welding Journal,2009,88(3):54-61.
[9]王煜,赵海燕,吴甦,等.电子束焊接数值模拟中分段移动双椭球热源模型的建立[J].机械工程学报,2004,40(2):165-169.Wang Yu,Zhao Haiyan,Wu Su,et al.Establishment of seg-mented moving double ellipsoid heat source model in electronbeam welding numerical simulation[J].Chinese Journal of Me-chanical Engineering,2004,40(2):165-169.
[10]王西昌,吴冰,左从进,等.电子束焊接数值模拟新型热源模型的初步探索[J].焊接学报,2005,26(12):81-84.Wang Xichang,Wu Bing,Zuo Congjin,et al.New heat sourcemodel for numetical simulation of electron beam welding[J].Transactions of the China Welding Institution,2005,26(12):81-84.
[11]罗怡,许惠斌,李春天,等.真空电子束焊接热源建模及功率密度分析[J].焊接学报,2010,31(9):73-76.Luo Yi,Xu Huibin,Li Chuntian,et al.Heat source modelingand power density analysis for vacuum electron beam welding[J].Transactions of the China Welding Institution,2010,31(9):73-76.