Influence of Specific Surface Area and Particle Size Distribution on Reaction Behavior of Iron
The chemical and physical properties of Fe2O3 are undoubtedly important for MnZn ferrite.In this work,Fe2O3 powders with different industrial specific surface area(SSA)made by different processes including spray roasting and fluidized bed process of different supplier have been prepared.The SSA,particle size distribution,sintering reactivity,solid state reaction as well as magnetic properties of MnZn ferrite for iron oxides are comprehensively investigated.The results show that the primary particles size distribution of iron oxides made by fluidized bed process are sharp and less aggregated than that by spray roasting process,which results in low temperature formation of ZnFe2O4.The reaction temperature of zinc oxide and iron oxide decrease as the SSA of iron oxide increase.The primary particles of the fluidized bed Fe2O3 is around 0.2~0.3μm,which contributes to the highest green density and the highest sintered density without abnormal grain growth.The sintered parts of iron oxides processed by spray roasting process trigger the grain growth from 95%theoretical density,as well as wet milled SB-Fe2O3 of China Steel Corporation(CSC).However,iron oxides by fluidized bed process sustain 98%theoretical density without abnormal grain growth due to the tight particle size distribution with well-controlled particles size smaller than 44μm.High SSA of Fe2O3 shows high spinel formation with expansion and lowest peak temperature of expansion.Iron oxides with SSA of 4~4.5m2/g reveal the lower hysteresis loss(Ph)and the initial permeability enhances with the increase of SSA for low loss MnZn ferrites.For high permeability ferrite,the high SSA and few aggregation in iron oxide are beneficial to improve the initial permeability,which is also independent to loss factor of ferrites.
Iron oxide Specific surface area (SSA) Permeability Power loss Ruthner Spray roasting Lurgi fluidized-bed
Hung Y.H. Chen P.W. Yeh S.W. Tseng Y.R.
New Materials R&D Department,China Steel Corp.(CSC),1 Chung Kang Rd.,Hsiao Kang,Kaohsiung 81233,Chin Himag Corporation(CSC Group),24-1,Chien Kuo Rd.,Nei-Pu Industrial Dist.,Ping Tung 91252,Chinese Taip
国际会议
北京
英文
1501-1508
2018-09-16（万方平台首次上网日期，不代表论文的发表时间）