Evidence for a High Temperature Whisker Growth Mechanism Active in Tungsten during In Situ Nanopillar Compression.

A series of nanopillar compression tests were performed on tungsten as a function of temperature using in situ transmission electron microscopy with localized laser heating. Surface oxidation was observed to form on the pillars and grow in thickness with increasing temperature. Deformation between 850 °C and 1120 °C is facilitated by long-range diffusional transport from the tungsten pillar onto adjacent regions of the YO-stabilized ZrO indenter.

In Situ Transmission Electron Microscopy for Ultrahigh Temperature Mechanical Testing of ZrO.

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 % ScO-stabilized ZrO up to its melting temperature. The results suggest that the low-temperature strength of nanograined, < 50 nm, oxides is not influenced by creep.