Synthesis of the Plasma Chemistry Occurring in High Power CO2Lasers.

摘要

The neutral chemistry of the following mixtures have been studied by using a quadrupole mass spectrometer and a theoretical model: CO2/Ar, N2/Ar, CO2/N2/Ar, CO2/He/Ar, and CO2/N2/He/Ar. CO2 dissociation occurs by direct electron impact and appears to depend on initial CO2 concentration and mixture. Very little N2 dissociation occurs in a pure N2 discharge; however, dissociation of N2 increases when it is added to a mixture containing CO2. This dissociation is less than 1%. Consequently, the dominant nitrogen oxide in mixtures containing CO2 and N2 is NO, and the concentration of NO never exceeds 1%. The species CHO and CH2O are present at high discharge currents if there is a small amount of water contamination in mixtures containing CO2. (Author)