In Situ Transmission Electron Microscopy for Ultrahigh Temperature Mechanical Testing of ZrO2
Abstract: This work demonstrates a novel approach to ultrahigh-temperature mechanical testing using a combination of in situ nanomechanical testing and localized laser heating. The methodology is applied to characterizing and testing initially nanograined 10 mol % Sc2O3-stabilized ZrO2 up to its melting temperature. The results suggest that the low-temperature strength of nanograined, d < 50 nm, oxides is not influenced by creep. Tensile fracture of ZrO2 bicrystals produce a weak-temperature dependence suggesting that grain boundary energy dominates brittle fracture of grain boundaries even at high homologous temperatures; for example, T = 2050 °C or T ≈ 77% Tmelt. The maximum temperature for mechanical testing in this work is primarily limited by the instability of the sample, due to evaporation or melting, enabling a host of new opportunities for testing materials in the ultrahigh-temperature regime.
Author(s): Grosso, R.L. ; Muccillo, E.N. S. ; Muche, D.N. F. ; Jawaharram, G.S.; Barr, C.M. ; Monterrosa, A.M. ; Castro, R.H. R. ; Hattar, K.; Dillon, S.J.
Nano Lett.
Published: January 13, 2020 Pages: 1041–1046