Fundamental Phenomena of Resistance Welding

Welding Procedures and Type IV Phenomena

In this work, we attempt a quantitative estimation of the type IV rupture stress for welds in ferritic power plant steels containing 9–12 wt. % chromium, using a neural network in a Bayesian framework. This article describes the methodology that was used in creating and evaluating the neural network model. The sensitivity of the rupture stress to the test conditions, the composition of the stee...

Fundamental aspects of X-ray photoacoustic phenomena

Modeling of transport phenomena in hybrid laser-MIG keyhole welding

Mathematical models and associated numerical techniques have been developed to investigate the complicated transport phenomena in spot hybrid laser-MIG keyhole welding. A continuum formulation is used to handle solid phase, liquid phase, and the mushy zone during the melting and solidification processes. The volume of fluid (VOF) method is employed to handle free surfaces, and the enthalpy meth...

Tunneling Phenomena in Cosmology: Some Fundamental Problems

The fundamental problem of how tunneling in thermal medium is completed is addressed, and a new time scale of order 1/friction for its termination, which is usually much shorter than the Hubble time, is pointed out. Enhanced non-linear resonance is responsible for this short time scale. This phenomenon occurs when the semiclassical periodic motion in a metastable potential well resonates with o...

Transport Phenomena and Keyhole Dynamics during Pulsed Laser Welding

Numerical and experimental studies were conducted to investigate the heat transfer, fluid flow, and keyhole dynamics during a pulsed keyhole laser welding. A comprehensive mathematical model has been developed. In the model, the continuum formulation was used to handle solid phase, liquid phase, and mushy zone during melting and solidification processes. The volume-of-fluid method was employed ...