An Efficient Small Scale TEA CO_2 Laser for Material Surface Modification

摘要

An efficient small scale TEA (Transversely Excited Atmospheric) CO_2 laser has been considered. The laser was a low flowing, UV preionized, pulsed system. Specific design of the head as well as the electrical circuit ensure the laser operation with high efficiency and reliability. Nonconventional CO_2/Y, Y= N_2/H_2; H_2/He and H_2 gas mixtures showed relatively high energy output. CO_2/N_2/H_2 mixture as the most superior one produces output energy and peak power of 220 mJ and 1.40 MW, respectively. High-energy output of the laser was employed for surface modification of austenitic stainless steel AISI 316 and titanium nitride (TiN) coating deposited on the same steel substrate. Used laser peak power densities of 100 and 170 MW/cm~2 have induced the morphology changes of AISI 316 steel and TiN coating, respectively.