Multi-phase ceramics based on ZrB_(2),TiB_(2) and doped with CrB_(2) and SiC were prepared by powder metallurgy and hot pressing to explore the possibility of obtaining multi-scale microstructures by super-saturation ...Multi-phase ceramics based on ZrB_(2),TiB_(2) and doped with CrB_(2) and SiC were prepared by powder metallurgy and hot pressing to explore the possibility of obtaining multi-scale microstructures by super-saturation of complex(Zr,Ti,Cr)B_(2) solid solutions.Core-shell structures formed in TiB_(2) grains,whereas ZrB_(2) appeared to form a homogeneous solid solution with the other metals.Precipitation of nano-inclusions within both micron-sized borides was assessed by transmission electron microscopy and thermodynamics elucidated the preferential formation of boride inclusions due to the specific sintering atmosphere.In addition,atomic size factors explicated the precipitation of CrB_(2) nano-particles into ZrB_(2)-rich grains and of ZrB_(2) nano-particles into TiB_(2)-rich grains.The hardness of the constituent phases measured by nanoindentation ranged from 36 to 43 GPa.展开更多
基金sponsored by the NATO Science for Peace and Security Programme under grant MYP-G5767 (SUSPENCE)by the US AFOSR through the grant no.FA9550-21-1-0399 (NACREOUS)with Dr.Ming-Jen Pan as contract monitor+1 种基金supply of laboratory facilities.NG acknowledges the support received by JECS Trust for a mobility grant (ref.2020240)of three months at UPC,SpainNanoindentation tests were funded through The Spanish Ministry of Science,Innovation and Universities through grant PGC-2018-096855-B-C41.S.Guicciardi (CNR-ISMAR)is acknowledged for discussion on nanoindentation.
文摘Multi-phase ceramics based on ZrB_(2),TiB_(2) and doped with CrB_(2) and SiC were prepared by powder metallurgy and hot pressing to explore the possibility of obtaining multi-scale microstructures by super-saturation of complex(Zr,Ti,Cr)B_(2) solid solutions.Core-shell structures formed in TiB_(2) grains,whereas ZrB_(2) appeared to form a homogeneous solid solution with the other metals.Precipitation of nano-inclusions within both micron-sized borides was assessed by transmission electron microscopy and thermodynamics elucidated the preferential formation of boride inclusions due to the specific sintering atmosphere.In addition,atomic size factors explicated the precipitation of CrB_(2) nano-particles into ZrB_(2)-rich grains and of ZrB_(2) nano-particles into TiB_(2)-rich grains.The hardness of the constituent phases measured by nanoindentation ranged from 36 to 43 GPa.
