Direct observation of toughening and R-curve behavior in carbon nanotube reinforced silicon nitride

SCRIPTA MATERIALIA

卷:124

Article

Vasudevan, Sugeetha¹  Kothari, Abhishek¹  Sheldon, Brian W.¹ 

[1] Brown Univ, Sch Engn, Providence, RI 02912 USA

关键词: Ceramic composites;    Carbon nanotubes;    Fracture toughness;    Nanoindentation;   

DOI  :  10.1016/j.scriptamat.2016.06.035

来源: Elsevier

【 摘 要 】

The efficacy of toughening in nanoscale ceramic composites is currently controversial, in part because indentation based fracture toughness measurements are not reliable in these materials. To explore the relevant mechanisms, in situ mechanical testing was used to investigate carbon nanotube reinforced silicon nitride. Nanoindentation of microcantilever beams (cut with a focused ion beam) made it possible to probe fracture and notch sensitivity. Stable crack growth was directly observed with this approach. The measured R-curve for these composites was obtained from analysis of these data. These results provide direct evidence of significant toughening enhancements in a carbon nanotube reinforced ceramic composite. (C) 2016 Elsevier Ltd. All rights reserved.

【 授权许可】

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