Translucent α- and α/β-SiAlON ceramics: study on investigation of the relationship between phase diversity and optical properties

Avcıoğlu S., Kurama S.

INTERNATIONAL JOURNAL OF MICROSTRUCTURE AND MATERIALS PROPERTIES, vol.15, no.1, 2020 (Scopus) identifier

  • Publication Type: Article / Article
  • Volume: 15 Issue: 1
  • Publication Date: 2020
  • Doi Number: 10.1504/ijmmp.2020.104609
  • Journal Name: INTERNATIONAL JOURNAL OF MICROSTRUCTURE AND MATERIALS PROPERTIES
  • Journal Indexes: Scopus, Aerospace Database, Communication Abstracts, Compendex, INSPEC, Metadex, Civil Engineering Abstracts
  • Keywords: AlN-polytypoids, Dopant, Microstructure, Optical properties, Phase composition, SiAlON, Spark plasma sintering, SPS, Transparent polycrystalline ceramics
  • Yıldız Technical University Affiliated: No

Abstract

In this study, Dy+3, Y+3, and La+3 doped SiAlON ceramics were fabricated by using spark plasma sintering (SPS) technique. The effects of additive cation, starting composition and processing conditions on the morphological evolution as well as on the phase assembly of SiAlON ceramics were investigated. The influence of phase diversity on the optical properties of SiAlON ceramics was also discussed. Results indicate that the translucent α-SiAlON, α/β-SiAlON ceramics and their in-situ composites with AlN-polytypoids could be successfully obtained. The presence of a high amount of secondary phases such as AlN-polytype and the oxynitride glassy phase has been found to reduce the optical transmission of SiAlON ceramics. The doping of Y+3 and Dy+3 cations contributed better to the formation of single-phase α-SiAlON than that of La+3. Doping SiAlON ceramics with Dy+3 cation leads to the formation of relatively homogenised final microstructure. Therefore, higher IR transmission values were observed on Dy-α-SiAlON (42.2%) and Dy-α/β-SiAlON (45.07%) samples.