So I just finished simulating and post-processing the results. You can find the project here: https://www.simscale.com/projects/ahmedhussain18/laser_hardening_of_helical_gear
All the description of the used formula can be found under project description.
Below is the figure taken in local Paraview in which slice and plot over line filters were used in order to get temperature plot so that the depth of laser can be measured. The red highlighted coordinates are of middle point which are also used to make a slice.
A less steep descent of temperature after 0.0015 shows that the total depth can be considered as 1.5 mm.
I hope this simulation will help you carry out further analysis in SimScale.
If you have any question/s, feel free to ask.