As indicated by the results, Al 2O 3 nano powder with an average grain size less than 30 nm and an evenly grain distribution and a low conglobulation can be obtained under such conditions as raw material concentration of 0.7 mol·L -1 ,pH=8, microwave treatment for 10 mins, heating at 650 ℃ for 2 hrs.
CoSb 3 micrometer powder was synthesized by solid state reaction using high purity powder of Co,Sb as the starting materials. CoSb 3 nano powder was prepared by high energy ball milling. CoSb 3 block material with the average grain size of 150nm was prepared by Spard Plasma Sintering(SPS).
In this paper, nano ZnFe2O4 powder was prepared by coprecipitation. XRD, XPS and SEM were used in analyzing structure characteristcs. Based on ZnFc2O4 nano powder thick film gas sensors were prepared, and their gas sensitive characteristics were tested and gas sensitive mechanism was given.
The results showed as follows:Method a) , phase transformation temperature of α -Al_2O_3 would be lowed to 950℃ withaddition of 1wt% seed ( α -Al_2O_3 nano powder) and 3wt% AlF_3 or 1wt% ZnF_2 and with milling 3h, and grain size of 30nm and 33nm respectively would be obtained for lh heat preservation.
Method b) , α -Al_2O_3 nano powder with grain size of 26nm can be prepared at 800 ℃ with addition of lwt% grain seed ( α -Al_2O_3 nano powder) and 1wt% ZnF_2, and with PEG as dispersant and by using alcohol as milling medium.
Preparation methods of Si C N nano powder, their advantages and disadvantages,the microstructure of Si N C nano powder and its microstructure transformation under different heat treatments are summarized,and the existing problems and future application prospects are presented.
The stability of a fumed aluminium oxide nano powder suspended in water has been assessed through measurement of zeta potential and streaming current, using the fact that the particles exhibit maximum repulsion at high magnitude of charge.
Formation characteristics of an aluminum hydroxide fiber by a hydrolysis of aluminum nano powder