Direct Numerical Simulation of Keyhole Instabilities and Bubbles Generation Processes during Deep Penetration Laser Welding of Titanium Alloy
A three dimensional self-consistent free surface model was developed to investigate transient keyhole dynamics during deep penetration laser welding of Titanium alloy. The evolutions of free surface keyhole profiles, weld pool shape and sizes, temperature fields and velocity fields of weld pool were calculated. Instabilities of the keyhole and formations of gas bubbles in the weld pool were directly numerically simulated. It was shown that during deep penetration laser welding of Titanium alloy the keyhole could oscillate throughout the welding process even in the absence of vapor plume. The keyhole instability was found to be closely associated with welding speed, surface tension as well as hydrodynamic pressure of fluid flow in the weld pool. The predicated penetration depth and porosity tendency in the final weld bead were also shown to correspond well with control experiments. The present theoretical model could be further improved as a fundamental tool for optimizing the laser welding process of Titanium alloys.
deep penetration laser welding titanium alloy keyhole instability bubble generation direct numerical simulation
S.Y.Pang L.L.Chen L.Chen T.Chen J.X.Zhou
State Key Laboratory of Materials Processing and Die&Mould Technology, Huazhong University of Scienc Science and Technology on Power Beam Processes Laboratory, Beijing Aeronautical Manufacturing Techno
国际会议
北京
英文
79-83
2010-10-25（万方平台首次上网日期，不代表论文的发表时间）