Numerical Simulation of Joining Process in a TIG Welding System Using Incompressible SPH Method

Abstract

An SPH simulation of a welding process is performed for TIG welding, taking account the melting and solidification of the anode metal, the free surface movement of the liquid, and the four dominant flow-driving forces; gradient of surface tension (Marangoni effect), gas drag on the liquid surface, buoyancy, and electromagnetic force (Lorentz force). The process of welding two metal blocks is computed, including the dynamic formation of weld pool which joins the gap between the blocks. The difference of material's surface tension dependency to temperature causes a significant difference in the weld pool penetration. These results show the usefulness of this particle method in arc welding simulations.

Particle simulation of nugget formation process during steel/aluminum alloy dissimilar resistance spot welding and thickness estimation of intermetallic compounds

“…ティグ溶接やミグ溶接の溶融池対流現象 [10][11][12][13] ，ミグ溶接やフ ラックスコアードアーク溶接の溶滴移行現象 14,15) ，サブマー ジアーク溶接現象 16) などの溶接・接合分野においても応用 されており [17][18][19][20][21]…”

Numerical Simulation of Molten Metal Droplet Behavior in Gas Metal Arc Welding by Three-Dimensional Incompressible Smoothed Particle Hydrodynamics Method

“…γ is the surface tension coefficient that is 1.0 N/m. attract ab f is the weighted function which is determined by the distance between particle a and b [15]. These indices L, S of surface tension vectors L F and LS F show the states of a particle.…”

Attempt to Suppress Numerical Viscosity in Incompressible SPH Method

“…Our research group has analyzed low Mach number flows in various fields, double-diffusive convection (Shigeta et al 2009), welding operation (Ito et al 2015), drifting object swept by sudden water flow (Wakui et al 2018) and flapping flags (Nishiura et al 2018), by incorporating an incompressible approximation technique into the SPH method. In this technique, incompressible flows are calculated by correcting the particle velocities at each time step while keeping the density variation relatively small.…”