CO2 laser heating of surfaces: Melt pool formation at surface

The melt pool formation during the heating of titanium and steel surfaces by a moving CO2 laser beam is examined. The repetitive pulses are introduced in the simulations and the Marangoni effect in the melt pool is incorporated in the model study. The influence of laser scanning speed and the laser intensity parameter on the melt pool size is also considered. The enthalpy–porosity method is adopted to account for the phase change in the irradiated spot. It is found that the influence of laser scanning speed on the melt pool size is considerable, which is more pronounced for laser beam parameter β=1. The melt pool size is smaller for stainless steel as compared to that corresponding to titanium.

► Repetitive pulses results in temperature ripples at the surface.
► Increasing laser scanning speed influences the melt pool geometry significantly.
► Partial melting of surface is resulted for laser pulse parameter beta=1.
► Melt pool shape predicted agrees well with the experimental data.