Effect of machine hammer peening on the surface integrity of a ZnAl-based corrosion protective coating

Timmermann, A.1, a; Abdulgader, M.2, b; Hagen, L.2, c; Koch, A.3, d; Wittke, P.3, e; Biermann, D.1, f; Tillmann, W.2, g; Walther, F.3, h

1)
Institute of Machining Technology, TU Dortmund University, Baroper Str. 303, D-44227 Dortmund, Germany
2)
Institute of Materials Engineering LWT, TU Dortmund, Leonhard-Euler-Str. 2, D-44227 Dortmund, Germany
3)
Department of Materials Test Engineering (WPT), TU Dortmund

a) alina.timmermann@tu-dortmund.de; b) mohamed.abdulgader@udo.edu; c) leif.hagen@tu-dortmund.de; d) alexander3.koch@tu-dortmund.de; e) philipp.wittke@tu-dortmund.de; f) dirk.biermann@tu-dortmund.de; g) wolfgang.tillmann@udo.edu; h) frank.walther@tu-dortmund.de

Abstract

Thermally sprayed protective coatings are applied onto many mechanically stressed components such as support structures, shafts, turbine blades or heat exchangers. In addition to the static or cyclic load, a superimposition with corrosion processes occurs in many cases. Thermal sprayed ZnAl coatings are known for their performant corrosion protection properties. Within this context, the potential of ZnAl-based layer systems was analyzed regarding corrosion fatigue behavior. Therefore, a timeand cost-efficient testing strategy based on a corrosion-superimposed load increase procedure was used to estimate the effects of a corrosive attack during cyclic loading. The investigated coating systems were thermally sprayed and partially post-processed with a Machine Hammer Peening (MHP) operation. This treatment was identified as an appropriate technique for compressing and smoothing coated surfaces. The inter-relationships between the parametrization of the MHP process, the resulting surface integrity, and the estimated corrosion fatigue properties were analyzed. The investigations indicate a positive effect of MHP post-processing operations on the surface properties of the ZnAl-based coating system.

Publication

7th International Conference of Materials and Manufacturing Engineering (ICMMEN 2020), (2020) 318, p. 6, doi: 10.1051/matecconf/202031801008