In-situ Mechanics of Materials by Pranjal Nautiyal & Benjamin Boesl & Arvind Agarwal

Author:Pranjal Nautiyal & Benjamin Boesl & Arvind Agarwal
Language: eng
Format: epub
ISBN: 9783030433208
Publisher: Springer International Publishing

High-temperature indentation is a useful approach to probe deformation in nanomaterial assemblies. Figure 4.4a shows the in-situ SEM indentation of a boron nitride nanotube “buckypaper,” consisting of a dense and entangled network of 1D nanotubes (Nautiyal et al. 2019b). Load–displacement plots showed similar deformation for room temperature and 250 °C indentation, but higher displacement for indentation at 500 °C (Fig. 4.4b). The elastic modulus showed a modest drop from ~1.2 GPa to ~0.9 GPa as the test temperature was increased from room temperature to 500 °C. Buckypaper response to compressive loading at different temperatures are shown in Supplementary Videos, Videos 4.2, 4.3, and 4.4. SEM imaging demonstrated that the buckypaper is highly flexible and damage tolerant. The videos show remarkable strain-redistribution ability due to interconnected microstructure, which prevents stress–concentration and local failure. The mechanical response was captured for 50 loading-unloading cycles and there were no signs of failure, indicative of fatigue-resilience at elevated temperatures. Supplementary Videos, Videos 4.5, 4.6, and 4.7 show cyclic deformation of BNNT buckypaper at room temperature, 250 °C and 500 °C, respectively. These mechanistic insights into high-temperature deformation of nanomaterials obtained are highly informative for engineering advanced structural composites.

Fig. 4.4The in-situ SEM indentation of a boron nitride nanotube buckypaper: (a) SEM micrographs showing indenter-induced stretching/deformation of buckypaper, and (b) load-displacement and elastic modulus response as a function of test temperature. (Reproduced with permission from Nautiyal et al. (2019b))

Download

Copyright Disclaimer:
This site does not store any files on its server. We only index and link to content provided by other sites. Please contact the content providers to delete copyright contents if any and email us, we'll remove relevant links or contents immediately.