Spark plasma sintered ZrC-TiC-GNP composites: Solid solution formation and mechanical properties


OCAK B. C. , Yavaş B., Akin İ., Şahin F., Göller G.

Ceramics International, vol.44, no.2, pp.2336-2344, 2018 (Peer-Reviewed Journal) identifier identifier

  • Publication Type: Article / Article
  • Volume: 44 Issue: 2
  • Publication Date: 2018
  • Doi Number: 10.1016/j.ceramint.2017.10.200
  • Journal Name: Ceramics International
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.2336-2344
  • Keywords: Zirconium carbide, Titanium carbide, Graphene nanoplatelets, Spark plasma sintering, Solid solution, DENSIFICATION BEHAVIOR, FRACTURE-TOUGHNESS, GRAPHENE, CARBIDE, MICROSTRUCTURE

Abstract

© 2017 Elsevier Ltd and Techna Group S.r.l.Graphene nanoplatelets were incorporated into (20-x)TiC-80ZrC(vol%) composite powder with x = 0, 0.5, 1, 2, 3, 6 and 9 vol% contents. The resulting powder mixture were sintered by spark plasma sintering (SPS) at 1700 °C under 40 MPa with 300 s holding time. The prepared composites were then characterized in terms of their densification, microstructure, mechanical properties and phase analysis. By the identification of phases by X-ray analysis, it is verified that Zr4+ ions in the crystal lattice replaced by Ti4+ ions and the substituted solid solution was formed. Almost fully dense ZrC-TiC-GNP composites containing 3 vol% GNP was obtained with a relative density of more than 99%. Vickers microhardness decreased with increasing GNP content, and ZrC-TiC-GNP containing 9 vol% GNP had the lowest value as 13 GPa. On the other hand, fracture toughness increased with increasing GNP content up to 3 vol%, and the maximum fracture toughness value was 5.17 MPa m1/2.