Bremen 2017 – wissenschaftliches Programm
P 16.4: Vortrag
Mittwoch, 15. März 2017, 09:40–09:55, HS 1010
Spectroscopic studies of active screen plasma nitrocarburizing processes comparing a steel and a carbon mesh as an active screen — •Constantin Rupp1, Stephan Hamann1, Andy Nave1, Igor Burlacov2, Heinz-Joachim Spies2, Horst Biermann2, and Jürgen Röpcke1 — 1INP Greifswald, 17489 Greifswald, Germany — 2TU Bergakadamie Freiberg, 09599 Freiberg, Germany
The active screen plasma nitriding (ASPN) is an advanced technology for the hardening of steel components. Additionally, carbon-containing gases such as CH4 and CO2 can be admixed to the N2-H2 gas achieving an active screen plasma nitrocarburizing (ASPNC) process. However, the amount of adding carbon-containing gases to the process is limited. As a new appraoch an active screen made of graphite is used as a carbon source.
This contribution presents the results of a spectroscopic study of N2-H2 containing pulsed DC plasmas in an industrial scale ASPN reactor using two different active screens (steel and graphite meshes) with an inner volume of about 1 m3. Based on optical emission spectroscopy (OES) the emission trends of H, N and N2 were qualitatively monitored. The concentration of CH4, NH3, C2H4, HCN and CO has been determined by the usage of infra-red laser absorption spectroscopy (IRLAS). The concentrations of the monitored species were found to be in the range of 1013 to 1015 molecules cm−3, whereby the concentrations of measured hydrocarbon components were found to increase significantly using a graphite mesh.