Fracture toughness of single grains and polycrystalline Li7La3Zr2O12 electrolyte material based on a pillar splitting method. Issue 8 (July 2020)

• Record Type: Journal Article
• Authors: Nonemacher, Juliane Franciele; Arinicheva, Yulia; Yan, Gang; Finsterbusch, Martin; Krüger, Manja; Malzbender, Jürgen
• Is Part Of: Journal of the European Ceramic Society. Volume 40:Issue 8(2020)
• Page Start: 3057
• Page End: 3064
• Publication Date: 2020-07
• Subjects: Solid electrolyte -- LLZO -- Fracture toughness -- Indentation -- Pillar splitting; Ceramic materials -- Periodicals; Composite materials -- Periodicals; Matériaux céramiques -- Périodiques; Composites -- Périodiques; Ceramic materials; Composite materials; Periodicals; Electronic journals; 666.05
• DOI: 10.1016/j.jeurceramsoc.2020.03.028
• Languages: English
• ISSNs: 0955-2219

Abstract

Highlights: The mechanical properties of LLZO with two different grain sizes were investigated. Large grain sample has higher E and H compared to small grain sample. Pillar splitting method was adopted to determine the fracture toughness. K IC obtained via pillar splitting agrees well with that via Vickers indentation. Grain boundaries show positive effect on K IC whereas negative on conductivity. Abstract: In the present study an advanced pillar splitting method is used to determine the fracture toughness of a garnet-type Li7 La3 Zr2 O12 (LLZO) electrolyte. The obtained results are compared to data derived on the basis of conventional Vickers indentation. Furthermore, potential micro-pillar size effects are investigated. The estimated fracture toughness values for single grains and polycrystalline LLZO material obtained via both methods are in good agreement, yielding ∼ 1 MPa m 0.5, hence the data indicate that LLZO exhibits relatively low fracture toughness and has a brittle behavior.