Study the keyhole welding performance with enthalpy method in upwind scheme

A keyhole welding code determining E.B (electron beam) welding performance was developed in this study. Here the wokpiece of SS304, subjected to incident energy density in Guassian distribution, is provided with constant feeding velocity, and a welded cavity, vapor-supported keyhole, is idealized to be a paraboloid of revolution. The present study finds that temperature along liquid - vapor interface, as a thermal boundary of keyhole, can be successfully estimated by implicit iteration from the Clausius-Clapeyron equation in hyper-geometric function. That also describes the local thermodynamics equilibrium of vapor pressure and surface tension. Meantime, the used upwind scheme in enthalpy function guarantees the continuity of thermal property across the melting front. By satisfying the energy conservation and second law of thermodynamics at cavity base, penetrating depth as well as welded temperature will be uniquely determined. From which, the numerical prediction is found to be agreement with experimental data of E.B welding performed in this study and a crucial factor responsible for the intensity of incident energy, energy distribution radius, is well presented here. © 2012 American Scientific Publishers All rights reserved.