Geometry Analysis in Arc Welding of Plates
The change in profile caused by melting, flowing, and solidifying in arc welding was numerically calculated. Two steel plates were heated to weld by a moving arc. The temperature distributions and molten regions in the plates were calculated by a finite element method and with an enthalpy method for phase change. The change in the surface profile of the molten pool under arc pressure and surface tension was calculated by a finite difference method. When the arc pressure was high, the bottom surface of the molten pool appeared and an unsatisfactory humped geometry remained after welding. When the heating rate or the electronic current of the welding was high,
a separated or undercut geometry remained after welding. The effects of arc pressure, heating rate, and welding arc's speed on the final geometry were obtained and used to determine optimum conditions. Temperature changes in a plate heated by a moving arc were measured. The experimental results agreed with the calculation results.