The differential analysis for temperature distribution diagnostics of arc current-carrying region in sheet slanting tungsten electrode inert gas welding with the electrostatic probe

Abstract

An electrostatic probe differential analysis method is used to diagnose the arc current-carrying region of the sheet slanting tungsten electrode. Based on the local thermal equilibrium condition and energy transition model with charged particles collision, the temperature distribution in the current-carrying region of different welding process parameters is solved by saturated ion current. The results show that the temperature distribution range in the width direction of sheet slanting tungsten electrode expands, the arc high-temperature region shifts integrally, and the temperature in the thickness direction of sheet slanting tungsten electrode would be symmetrical. The guide effect of the hypotenuse of sheet slanting tungsten electrode for arc current and the inertia drag effect of arc would mainly change the temperature distribution. The variation of the inclination angle of the hypotenuse of sheet slanting tungsten electrode will aggravate the shift of the arc high-temperature region. The larger inclination angle will enhance the guiding effect, and then the inertia drag effect would be in a dominant position with a smaller inclination angle. With the increase of welding current, both the arc stiffness and the guiding effect would be intensified, the latter should make the arc high-temperature zone shift to the position with a small discharge gap.

Keywords

• ultra-narrow gap welding
• welding arc
• temperature of the current-carrying region
• electrostatic probe