Synthesis and analysis of pure and metal-containing carbon coatings using HPPMS-PVD

• Applicant: Professorin Dr.-Ing. Kirsten Bobzin
• Subject Area: Coating and Surface Technology
• Term: from 2013 to 2021
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 235011713

The proposed project is based on the current project "HPPMS-C-Schichten" (BO 1979/33-1), which focuses on the deposition of a-C- and a-C:Me coatings for tribological applications by means of HPPMS (High Power Pulse Magnetron Sputtering) with varying energy input into the plasma. The use of neon as process gas led to an improvement of the coating properties. However, as a result of this project, a further improvement of the coating properties and the compound adhesion between coating and substrate of the deposited a-C(:Me) coatings is necessary in order to increase the suitability for tools in tribological applications such as Al machining. In this respect, promising results could be observed in our own preliminary work with the use of substrate temperatures TS < 250 °C as well as for a gradation of the substrate temperature. These effects should therefore be investigated in more detail for the deposition of a-C(:Me) coatings deposited by means of HPPMS.The overall objective of the proposed project is therefore a fundamental understanding of the cause-and-effect relationships of coating properties and the compound adhesion for the deposition of a-C and a-C:Me coatings by means of HPPMS at low substrate temperatures TS < 250 °C, in particular TS < 25 °C, and varying energy input into the plasma. For this purpose, the influence of the above-mentioned process parameters on basic coating properties such as the microstructure, the sp3/sp2 bond ratio or the residual stresses are correlated with the application-relevant mechanical properties, the compound adhesion and the thermal stability of the deposited coatings. The result of these investigations is a not yet available modified structure-zone model as well as a modeling of the cause-effect relationships for the low-temperature range TS < 250 °C for a-C(:Me) coatings. A further aim is the explanation of the influence of a substrate temperature gradation on the coating properties and the compound adhesion as well as the thermal resistance. The findings are intended to enable a targeted development of a-C(:Me) coatings on steel or hard metal substrates on tools for tribological applications. The substrate temperature is varied from TS = -90 °C to TS = 250 °C using a liquid contact cooling of the substrate holder. The variation of the energy input into the plasma is realized with different peak powers per pulse for the HPPMS. According to the findings of the ongoing project BO 1979/33-1 neon is used as process gas. For comparability, a-C(:Zr) coatings are considered. The investigations are as in BO 1979/33-1 carried out in a large-volume coating plant.

• DFG Programme: Research Grants
• Major Instrumentation: Temperiereinheit inkl. Anschlussperipherie ; UV-Erweiterung für MikroRaman-Spektrometer
• Instrumentation Group: 1840 Raman-Spektrometer ; 8500 Kältemaschinen (bis -100 Grd C), Eiserzeuger, Rückkühlanlagen