Next Article in Journal
Revisiting the Birth of 7YSZ Thermal Barrier Coatings: Stephan Stecura
Previous Article in Journal
Phase Composition, Thermal Conductivity, and Toughness of TiO2-Doped, Er2O3-Stabilized ZrO2 for Thermal Barrier Coating Applications
Article Menu
Issue 7 (July) cover image

Export Article

Open AccessArticle

Cavitation Erosion Resistance and Wear Mechanism Model of Flame-Sprayed Al2O3-40%TiO2/NiMoAl Cermet Coatings

Department of Materials Engineering, Faculty of Mechanical Engineering, Lublin University of Technology, Nadbystrzycka 36D, 20-618 Lublin, Poland
*
Author to whom correspondence should be addressed.
Coatings 2018, 8(7), 254; https://doi.org/10.3390/coatings8070254
Received: 5 June 2018 / Revised: 13 July 2018 / Accepted: 19 July 2018 / Published: 21 July 2018
  |  
PDF [56893 KB, uploaded 21 July 2018]
  |  

Abstract

This manuscript deals with the cavitation erosion resistance of flame-sprayed Al2O3-40%TiO2/NiMoAl cermet coatings (low-velocity oxy-fuel (LVOF)), a new functional application of cermet coatings. The aim of the study was to investigate the cavitation erosion mechanism and determine the effect of feedstock powder ratio (Al2O3-TiO2/NiMoAl) of LVOF-sprayed cermet coatings on their cavitation erosion resistance. As-sprayed coatings were investigated for roughness, porosity, hardness, and Young’s modulus. Microstructural characteristics of the cross section and the surface of as-sprayed coatings were examined by light optical microscopy (LOM), scanning electron microscopy (SEM) with energy-dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) methods. Coating cavitation tests were conducted in accordance with the ASTM G32 standard using an alternative stationary specimen testing method with usage of reference samples made from steel, copper, and aluminum alloys. Cavitation erosion resistance was measured by weight and volume loss, and normalised cavitation erosion resistance was calculated. Surface eroded due to cavitation was examined in successive time intervals by LOM and SEM-EDS. On the basis of coating properties and cavitation investigations, a phenomenological model of the cavitation erosion of Al2O3-40%TiO2/NiMoAl cermet coatings was elaborated. General relationships between their properties, microstructure, and cavitation wear resistance were established. The Al2O3-40%TiO2/NiMoAl composite coating containing 80% ceramic powder has a higher cavitation erosion resistance than the reference aluminium alloy. View Full-Text
Keywords: cermet coating; aluminia–titania; thermal spraying; flame spraying; cavitation erosion; microstructure; wear model cermet coating; aluminia–titania; thermal spraying; flame spraying; cavitation erosion; microstructure; wear model
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Szala, M.; Hejwowski, T. Cavitation Erosion Resistance and Wear Mechanism Model of Flame-Sprayed Al2O3-40%TiO2/NiMoAl Cermet Coatings. Coatings 2018, 8, 254.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Coatings EISSN 2079-6412 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top