Umschmelzen von Guß mit CO2-Laserstrahlung

Laser surface melting of an alloy cast iron containing undercooled spheriodal graphite was investigated using high power CO2 laser radiation by variation of laser power, beam distribution, beam diameter, and transverse speed resulting in different power densities interaction times in order to achieve different heating and cooling rates and case depths with respect to surface finish, crashing, and overlapping effects of melt tracks covering substantial surface areas. The design and the flow characteristics of the gas handling system are varied with the composition of shielding and alloying gas to relate processing conditions to dimensions, solute content, microstructural refinement of laser melted and heat affected zone, and resulting metallurgical and mechanical properties. (ILT)