Near the Ablation Threshold of Copper Surface Which Irradiated by 10.6 µm CO2 Laser Beam

In this paper, the ablation threshold of several metals has been considered by analogize the characteristics such as: fluence, specific heat of vaporization, and deposited energy. Analytically, the results showed that the threshold ablation happens when copper surface is radiated by CO2 laser pulses. Experimental observations showed the evaporation for Al and Zn and ablation threshold on Cu as expectation. Thereby, the analytical results have been confirmed by the experimental observation, completely. Oxidation has been observed on Cu surface in phase of Cu2O, particle sizes are around 200nm. The scanning electron microscope (SEM) image from the radiated surface clearly showed the starting point of the ablation, while the separation not happened, yet. Thus, observation could be interpreted as the ablation threshold. Notably, it could be concluded as such: first, the ablation threshold happens on the interaction of pulsed CO2 laser with copper surface. Second, observation on mentioned threshold approves the possibility of Cu2O nanoparticles synthesis by nanosecond CO2 laser in free space without a reactor.