Development of Suspension Feedstocks for Thermally Sprayed Zn2TiO4 Coatings

Research output: Contribution to journalResearch articleContributedpeer-review

Contributors

  • Anja Meyer - , Fraunhofer Institute for Ceramic Technologies and Systems (Author)
  • Filofteia Laura Toma - , Fraunhofer Institute for Material and Beam Technology (Author)
  • Oliver Kunze - , Chair of Materials Technology, Fraunhofer Institute for Material and Beam Technology (Author)
  • Andreas Böhme - , Fraunhofer Institute for Ceramic Technologies and Systems (Author)
  • Björn Matthey - , Fraunhofer Institute for Ceramic Technologies and Systems (Author)
  • Annegret Potthoff - , Fraunhofer Institute for Ceramic Technologies and Systems (Author)
  • Arno Kaiser - , Fraunhofer Institute for Ceramic Technologies and Systems (Author)
  • Tim Gestrich - , Fraunhofer Institute for Ceramic Technologies and Systems (Author)
  • Christoph Leyens - , Chair of Materials Technology, Fraunhofer Institute for Ceramic Technologies and Systems (Author)

Abstract

By adjusting the thermal spraying suspension technology, coatings with excellent microstructure, surface morphology, and phase composition can be obtained to meet the application needs in mechanical, electrical or friction fields. The use of suspensions as feedstock material allows a high degree of flexibility with regard to the chemical composition of the sprayed coatings. Moreover, suspension thermal spraying (STS) is a promising technique for the production of coatings, the use of which was previously limited by expensive starting materials. A mixture of less expensive starting materials in the suspension and an "in situ" reaction to the desired product during the spraying process make this possible. Zn2TiO4 coatings are one example where the high costs of blended oxide powders as feedstock material hinder the market introduction, whereas their outstanding electrical properties and photocatalytic activity are of great interest for various industrial applications. In this work, single oxides ZnO and TiO2, Zn acetate salt as ZnO precursor, as well as a Zn2TiO4 powder were used to develop tailored aqueous suspension feedstocks suitable for thermal spraying. To follow the formation of the compositions in the system ZnO-TiO2, differential thermal analysis (DTA) measurements were performed. Preparation routes of stable suspensions and suspension-solution mixtures with low sedimentation rates, low viscosities and good flowabilities are discussed. Microstructures and phase compositions of sprayed coatings are shown, and the “in situ” formation of Zn2TiO4 phase during Suspension High Velocity Oxygen Fuel Spraying (S-HVOF) is demonstrated. This work shows the high potential of suspension feedstocks from single oxide raw materials to obtain Zn2TiO4 sprayed coatings.

Details

Original languageEnglish
Pages (from-to)502-513
Number of pages12
JournalJournal of thermal spray technology
Volume32
Issue number2-3
Publication statusPublished - Mar 2023
Peer-reviewedYes

Keywords

Keywords

  • feedstock preparation, microstructure, phase composition, solution precursor spraying, suspension, suspension spraying, zinc Titanium Oxide