Calculation of Solid Wire Melting Rate in CO2 Welding

The melting rate of solid wire was studied both theoretically and experimentally during CO2 arc welding. The effects of welding current, an electrode diameter, and its extension, as well as droplet enthalpy on melting rates, were evaluated. The calculation methods of solid wire melting rate known as the coefficient of melting and having the dimension [g.A(-1).h(-1)] are proposed. The first mathematical model was created using a theoretical equation derived from the thermal equality of the heat runoffs and sources existing in electrode extension. The mathematical relationship between welding variables (the density of welding current and the electrode extension) and droplet enthalpy was derived using the regression analysis of experimental data. The second mathematical model is a regression equation, which connects the coefficient of melting with welding current, electrode diameter, and its extension. Its coefficients were derived from the researchers' experimental data. Both models allow calculating the coefficient of melting with an acceptable magnitude of error.