Evaluation of the mechanical properties of plasma-sprayed coating by nanoindentation technology

¹ LTAS/MN 2L, Aerospace & Mechanical Engineering Department, University of Liège, 4000 Liège, Belgium
² Engineering Simulation and Aerospace Computing, the Key Laboratory of Contemporary Design & Integrated Manufacturing Technology, Northwestern Polytechnical University, Xi’an, 710072 Shaanxi, China
³ Department of Advanced Materials and Structures, Centre de Recherche Public Henri Tudor, 4221 Esch-sur-Alzette, Luxembourg
⁴ Plasma Technology Research Center (CRTP), Department of Chemical Engineering, University of Sherbrooke, Sherbrooke, Québec, Canada J1K 2R1

^a Corresponding author: JP.Ponthot@ulg.ac.be

Received: 17 February 2011
Accepted: 13 June 2012

Abstract

In this paper, the mechanical properties of plasma-sprayed coatings are evaluated using the technology of nanoindentation. According to the indentation curve (load versus indenter’s displacement), which is recorded in an indentation experiment, the mechanical behaviour of the plasma-sprayed coating is investigated via inverse analysis using numerical optimization algorithms. The tip rounding of imperfect indenter is investigated in parameter identification. Subsequently, the hardness on the top surface and on the vertical cross section of the plasma-sprayed coating are investigated. The results show that the hardness on the top surface of the coating depends on the indentation depth. Moreover, the results show that the hardness on the cross section of the coating is significantly affected by the substrate if the indentation impression is too close to the coating-substrate interface.