文档介绍：謦5143 ss
激光深熔焊接小孔效应的理论和试验研究
摘 要
本文采用理论和试验相结合的方法系统地研究了激光深熔焊接GGl7(Pyrex) 玻璃时的小孔效应。论文首先使用德国Prometec公司生产的Laserscope UFFl00 大功率激光束光斑诊断仪测定了激光束的模式,并采用高速摄影的方法清晰、完整地观测到了激光深熔焊接GGl7玻璃时小孔的形状,为试验研究激光深熔焊接时的小孑L效应提供了一种试验方法。然后,论文根据实验得到的小孔形状,建立了深熔焊接的纯热传导模型和热传导加对流换热模型,并分别采用差分法和使用 ANSYS有限元分析软件进行了数值模拟计算。最后,论文针对两类模型的计算结果以及试验结果,研究了聚焦光斑尺寸、离焦量、焊接速度等焊接工艺参数对小孔和熔池尺寸、形状的影响。
关键词:激光焊接小孔效应ANSYS有限元分析
A Theoretical and Experimental Study on Keyhole
Effects in Laser Deep ration Welding
The k劬oIe effects in deep-ration laser welding of GGl7俨yr懿)glass are theoretically and experimentally studied in this of all,the LASERSCOPE UljF]00,a diagno蚶c instrument for the measurement and monitoring of high-power material process lasers,is used to measure beam width,diveagence angle and beam propagation the same time,a keyhole can be clearly observed by a high—speed camera while welding and a technique of laser welding glass GGl7(Pyrex)WaS
developed to get clear photographs of the keyhole for quantitative ,a
theory model for only considering simple conduction and a mathematic model for taking into acgotmt both coI妣ddon and convection in the welding pool are generally
two types of models ale calculated pared with Finite Difference
Method(FDM)and Finite Element Method㈣,according to the
results of calculating two types of models and the datas obtained丘om the
deep-ration laser welding experiments of G017 glass,the effects of such parameters as the size offocal spot,focal position and welding speed on the shape and fee ofthe keyhole are investigated.
Keywords:Laser welding keyhole effects ANSYS FEM
激光深熔焊接小孔效应的理论和试验研究
详细摘要
研究生 张屹
指导老师 李力钧 教授中文摘要(略) Abstract(略)
第一章 概论
随着大功率激光器的出现,尤其是激光,竦的功率密度地不断提高,激光深熔焊接技术在工业生产中的应用日益广泛。本章首先在综述中谈到了激光焊接的本质特征是存在着小孑【{*深捧;焊接研究的热点和难点。接着本章简单阐述了小孔作用的机理、小孔的两种吸收机制——小孔孔壁的反射吸收和等离子体的反韧致辐射吸收,回顾了激光焊接数学模型的发展概况。
第二章 激光焊接小孔的试验研究
本章首先使用UFF--100,采用3点测量法可以测得激光M2,试验中使用的激光器为自制的PHC-- 26,为近基模激光。然