Core-shell structure: An effective feature for strengthening ZrB2 ceramics

SCRIPTA MATERIALIA

卷:160

Article

Silvestroni, Laura¹  Failla, Simone^1,2  Vinokurov, Vladimir³  Neshpor, Irina³  Grigoriev, Oleg³ 

[1] CNR ISTEC, Natl Res Council Italy, Inst Sci & Technol Ceram, Via Granarolo 64, I-48018 Faenza, Italy

[2] Univ Parma, Dept Chem, Life Sci & Environm Sustainabil, Parco Area Sci 11-a, I-43124 Parma, Italy

[3] IPMS, Frantsevich Inst Problems Mat Sci NAS Ukraine, 3 Krzhizhanovskoho St, UA-03680 Kyev, Ukraine

关键词: Borides;    Core-shell;    Creep;    Dislocation mobility;    Grain boundaries;   

DOI  :  10.1016/j.scriptamat.2018.09.024

来源: Elsevier

【 摘 要 】

Hot compression behavior of two ZrB2 ceramics containing SiC or WSi2 particles was investigated upon stepwise heating from 1700 to 2100 degrees C under static load in vacuum. Presence of SiC activated notable creep already at 1700 degrees C, owing to diffused silica softening at SiC/SiC interfaces, whilst for WSi2 appreciable deformation occurred only above 1900 degrees C. Limited amount of SiC particles, which is responsible for cavitation, and formation of (Zr,W)B-2 solid solution, able to accommodate high mechanical loads through plastic deformation, are fundamental characteristics to remarkably perform in hot environments. Particularly, dislocation activity in the solid solution plays a fundamental role at ultra-high temperatures. (C) 2018 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

【 授权许可】

Free