CNT/Fe/Al2O3 mixed powders were synthesized from Fe/Al2O3 nanopowders using thermal CVD for the homogeneous dispersion of carbon nanotubes CNTs. CNTs consisted of MWNT, and the diameter was approximately 20-30 nm. Aft...CNT/Fe/Al2O3 mixed powders were synthesized from Fe/Al2O3 nanopowders using thermal CVD for the homogeneous dispersion of carbon nanotubes CNTs. CNTs consisted of MWNT, and the diameter was approximately 20-30 nm. After sintering, CNTs were homogenously located throughout Al2O3 grain boundary and were buckled. A femto-second laser installed with special optical systems was used for micromachining of the nanocomposites. The relationship between material ablation rate and energy fluence was theoretically investigated and compared with experimental results from cross-sectional SEM analysis. The nanocomposites which have higher content of CNT show a fairly good machining result due to its higher thermal conductivity and smaller grain size as well as lower light transmittance.展开更多
SiO2 coated γ-Fe2O3 nanocomposite powder has been successfully synthesized by chemical vapor condensation process and its feasibility on hyperthermic application was investigated in this study. The power loss of SiO2...SiO2 coated γ-Fe2O3 nanocomposite powder has been successfully synthesized by chemical vapor condensation process and its feasibility on hyperthermic application was investigated in this study. The power loss of SiO2 coated γ-Fe2O3 nanocomposite powder which means the magnetic heating effect under alternative magnetic field was much higher than the single phase γ-Fe2O3 nano powder due to the very fine size under 20 nm and well dispersion in biologically compatible SiO2 matrix. The superparamagnetism and hyperthermic property of SiO2 coated γ-Fe2O3 nanocomposite powder were discussed in terms of microstructural development in this study.展开更多
基金supported by a grant from the National Core Research Center Program funded by KOSEF and MOST (R15-2006-022-01001-0 and R15-2006-022-01003-0)
文摘CNT/Fe/Al2O3 mixed powders were synthesized from Fe/Al2O3 nanopowders using thermal CVD for the homogeneous dispersion of carbon nanotubes CNTs. CNTs consisted of MWNT, and the diameter was approximately 20-30 nm. After sintering, CNTs were homogenously located throughout Al2O3 grain boundary and were buckled. A femto-second laser installed with special optical systems was used for micromachining of the nanocomposites. The relationship between material ablation rate and energy fluence was theoretically investigated and compared with experimental results from cross-sectional SEM analysis. The nanocomposites which have higher content of CNT show a fairly good machining result due to its higher thermal conductivity and smaller grain size as well as lower light transmittance.
基金supported by a grant-in-aid for the National Core Research Center Program from the Ministry of Science & Technology and the Korea Science & Engineering Foundation (R15-2006-022-03001-0)
文摘SiO2 coated γ-Fe2O3 nanocomposite powder has been successfully synthesized by chemical vapor condensation process and its feasibility on hyperthermic application was investigated in this study. The power loss of SiO2 coated γ-Fe2O3 nanocomposite powder which means the magnetic heating effect under alternative magnetic field was much higher than the single phase γ-Fe2O3 nano powder due to the very fine size under 20 nm and well dispersion in biologically compatible SiO2 matrix. The superparamagnetism and hyperthermic property of SiO2 coated γ-Fe2O3 nanocomposite powder were discussed in terms of microstructural development in this study.
