Characterization and applications of direct current microarcs: a review
Margarita Baeva, Dirk Uhrlandt
Abstract
Abstract An overview of the applications and the characterisation of micro-sized direct current arcs is provided, with emphasis on their classification among other discharge kinds (glow discharges, sparks, gliding and thermal arcs). Industrial applications such as micro plasma arc welding, wire arc additive manufacturing, and low-voltage switching are considered and typical operating conditions are given. Specific diagnostic studies, which are reported so far, are summarised to present electrical and spectroscopic measurements, and selected findings. The modelling of microarcs is described and the available approaches are explained. The equations for a self-consistent fluid modelling of microarcs and their electrodes are presented with the main focus on the unified description of the plasma region and the boundary conditions. This description provides the spatial structure and the plasma parameters, which can hardly be obtained in experiments. Simulation results for various gases and cathode types are presented in relation to applications included in the review.