抄録
The change in profile caused by melting, flowing, and solidifying in the arc welding of plates was numerically calculated. 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 wavy or humped geometry remained after welding. The effects on the final geometry of the arc pressure, of the heating rate, and of the welding moving speed were obtained and used to determine optimum conditions.