Laser Welding of a Spark Plug Electrode: Modelling the Problem of Metals with Disparate Melting Points
R. Banak, T. Moscicki, S. Tofil, J. Hoffman and B. Antoszewski
The numerical model of laser welding is presented. The time dependent set of equations describing heating, melting and solidification is solved using ANSYS-Fluent package and adopted to the problem using the external user-defined functions. The developed model is used for investigation of laser welding of Ir pad with spark plug electrode made of Ni. These spark plugs are key parts of industrial internal combustion engines using biogas as fuel. Problems in welding arise from significant difference of melting points of both metals; moreover, the boiling point of Ni is close to melting point of Ir. Theoretical model of the welding process is a useful and cost lowering tool providing guidance for selection of parameters and reducing significantly number of expensive and time consuming experiments.
Keywords: Nd:YAG laser, iridium, Ir, nickel, Ni, spark plug, laser welding, numerical model, dissimilar metals welding, temperature dependent material properties