Measurement of Fusion Boundary Energy Transport During Arc Welding

Abstract

An experimental technique is presented to identify fusion boundary (liquid/solid interface) energy transport mechanisms during welding procedures. The gas-tungsten-arc spot-welding procedure, using a low melting point specimen material (lead), was chosen to demonstrate the methods. Vaporization energy losses were found to be important during the growth of the fusion boundary. Significant thermal convection was absent within the weld pool for applied currents less than about 100 A, and for such cases the location of the fusion boundary was found to be governed primarily by heat conduction. At the current levels of almost 300 A, significant weld pool convection was found to exist, especially at the (inner) stagnation point, causing a deeper penetration of the fusion boundary there.

An analytical model of energy distribution in laser direct metal deposition

“…For typical DMD materials such as stainless and H13 steels, and at the lower laser intensities used for this process, boiling losses can be considered insigni®cant and only evaporation losses considered [46]. Landram [47] concluded that evaporation losses were more important than convection in determining heat transfer to the melt pool boundary (the fusion zone in welding) and Salcudean et al [48] noted that they are sensitive to the power distribution (the largest loss is caused by a concentrated¯ux acting uniformly). Dykhuizen and Dobranich drew attention to the applicability of this pathway to DMD [15].…”

Application des capteurs thermiques implantés pour la détection du profil de gelée dans la cuve d'électrolyse /

“…C'est pour une application à la soudure qu'une première étude a été publiée [Landram 1983]. Des expériences en laboratoire, dans lesquelles un courant entre une cathode et une anode a fait fondre un morceau de plomb dans une cavité de nickel en demi-sphère, ont été menées.…”