The effect of Marangoni-Rayleigh-Benard convection on the process parameters in blown-powder laser cladding process - A numerical investigation

A two-dimensional model has been developed for the blown-powder laser cladding process to study the influence of Marangoni-Benard and Rayleigh-Benard convection on the process parameters: average dilution, maximum and average melt pool temperatures. Dimensionless governing equations are solved by the finite-volume method. It is found that for Marangoni number, Ma< 0 dilution decreases whereas for Ma> 0 dilution increases slightly. Rayleigh-Benard convection reduces dilution, but its effect is more prominent for Ma> 0 and lower scanning speed. Maximum and average melt pool temperatures fall due to convective heat transfer. However, the reduction in temperature with Ma not equal 0 is significant only at low scanning speeds, i.e., U*< 2.