Localized anodization of the aluminum alloy EN AW-7075 T6 by closed electrolytic free jet

21st Chemnitz Seminar on Materials Engineering – 21. Werkstofftechnisches Kolloquium

Morgenstern, R.^1 ; Martin, A.^2 ; Lehnert, N.^2 ; Scharf, I.^1 ; Hackert-Oschätzchen, M.^2 ; Schubert, A.^2 ; Lampke, T.^1

Institute of Materials Science and Engineering, Chemnitz University of Technology, Chemnitz

09125, Germany^1

Institute for Machine Tools and Production Processes, Chemnitz University of Technology, Chemnitz

09125, Germany^2

关键词: Coating microstructures;    Current distribution;    Functional surfaces;    Laser scanning microscope;    Processing parameters;    Surface structuring;    Tribological applications;    Tribological behaviors;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/480/1/012015/pdf
DOI  :  10.1088/1757-899X/480/1/012015

来源: IOP

【 摘 要 】

Anodizing with closed electrolytic free jet enables the resource-efficient, local conversion and surface structuring of the high-strength alloy EN AW-7075 T6 aiming at the local improvement of the tribological behavior of functional surface areas. The objective of the present work was to confine the current distribution on the specimen's surface and to achieve a stronger localization of the coating oxide layer. For this purpose, the processing parameters working distance, voltage and process duration were varied systematically. Based on the refractive index of the porous oxide and laser scanning microscope imaging of the interference lines, the maximum thicknesses of the anodized spots were calculated. Moreover, the coating microstructure was investigated by scanning electron microscopy and the surface topography was measured with a stylus profiler. The results show that the reduction of the working distance to 100 μm enables a significantly improved localization of the coating growth at substantially lowered process voltages. Thus, the energy-efficient production of localized, wear-resistant oxide spots for tribological applications with local functionalization of surfaces through anodization by closed electrolytic free jet is proven.