Experimental investigations and thermodynamic calculations of the interface reactions between ceramic moulds and Ni-based single-crystal superalloys: Role of solubility of Y in the LaAlO3 phase

Research output: Contribution to journalArticle

Authors

  • Hang Wang
  • Genfeng Shang
  • Jinfa Liao
  • Bin Yang
  • Chen Yuan

Colleges, School and Institutes

External organisations

  • Institute of Engineering Research, Jiangxi University of Science and Technology, Ganzhou 341000, China
  • School of Materials Science and Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, China

Abstract

It is commonly recognised that more reactive elements contained in Ni-based superalloy result in more-severe interfacial reactions, and thus more inclusions formed at the interface. However, the present work revealed that with rare-earth elements, specifically 0.24 wt.% La+Y added to Ni-based superalloys, the interfacial reaction (~5 µm in thickness) between the ceramics and metal was retarded compared to the case of 0.12 wt.% Y (~10 µm in thickness). Scanning electron microscopy, focused ion-beam transmission electron microscopy, and X-ray photoelectron spectroscopywere used to characterise the microstructure at the interface. Thermodynamic calculations of the Gibbs free energies of interfacial reactions were conducted. Experimental and theoretical results show that the solubility of Y in the LaAlO3 phase (>3.4 at.%) hinders interfacial reactions

Details

Original languageEnglish
Pages (from-to)7667-7673
JournalCeramics International
Volume44
Issue number7
Early online date2 Feb 2018
Publication statusPublished - 1 May 2018

Keywords

  • ceramic mould , Ni-based superalloys , interfacial reaction , rare-earth elements , thermodynamic calculations