Hannover 2020 – scientific programme
The DPG Spring Meeting in Hannover had to be cancelled! Read more ...
Parts | Days | Selection | Search | Updates | Downloads | Help
P: Fachverband Plasmaphysik
P 5: Poster Session 1
P 5.23: Poster
Monday, March 9, 2020, 16:30–18:30, Empore Lichthof
Study of the local segregation of multi-component powders during a plasma spray process — •Thorben Kewitz1, Holger Testrich1, Antje Quade1, Katja Fricke1, Maik Fröhlich1,2, Rüdiger Foest1, and Klaus-Dieter Weltmann1 — 1Leibniz Institute for Plasma Science and Technology, Greifswald, Germany — 2University of Applied Sciences Zwickau, Zwickau, Germany
Plasma spraying is an atmospheric pressure coating process. The coatings can be utilized e.g. for wear, corrosion and heat protection or for biomedical applications. The use of powder mixtures consisting of different components allows the extension of specific coating properties. For instance, by addition of a small amount of Cu to TiO2 powder antimicrobial coatings on implant surfaces can be achieved. Our investigations show that the different powders in the mixture can segregate during the plasma spray process on the way from the injection to the substrate. The segregation of the different powders can be ascribed to different material densities and particle sizes (a few tens microns in diameter) of the constituents. The segregation causes gradients in the chemical composition of the coating. During static deposition experiments with mixtures of TiO2 and 3% Cu, a segregation of the resulting profiles of up to 2 cm was observed and verified by XPS analysis. Depth profiles were prepared and analyzed with SEM. The results show that it is important that the particle sizes are selected carefully considering also the material densities as prerequisite for spatially homogeneous coatings. Yet, the segregation can also be used for generating coatings with controlled material gradients.