Research On The Application Of Pre-sintering Materials Of Hard Ferrite With High Grade

In order to make use of labor power, material resources, financial resources, financial resources and natural resources in the PanZhiHua iron and steel company, to develop the district of high-grade magnetic material and establish magnetic material industry production base in the west region of China, this paper focus on the study of the application technology of hard ferrite pre-sintering material with high-quality.Hard ferrite, especially those with high-properties, is the basic functional material in the modern society. Study of hard ferrite with high properties can improve the development of information technology, environmental protection and modern automobile industry.In this paper, the application and research status of magnetic materials, the development distinctions of magnetic industry between China and foreign country, the development strategies of hard ferrite, and the advantages and significance for developing magnetic industry in PanZhiaHua district was introduced. On the base of the analysis on the advanced technology of hard ferrite in foreign country, the main procedures of preparing hard ferrite pre-sintering material are determined as follows: First, the ferrite oxides coming from the main cold rolling line and strontium carbonate are conveyed to storage tank by gas power and weighed automatically according to the demands of constituent composition . And then they are mixed and grinded by using method of wet treatment. Finally the mixtures is transported to the devices of storage by transporting pump. After this, they are quantitatively weighed at quantitative pump again and sent to rotary kiln to be sintered with wet method. The products of pre-sintering material are cooled to room temperature at low speed after sintering and grinded by ball-grind. The pre-sintering materials of high quality hard ferrite are prepared.The research work in this paper was carried out at the second power factory of XiCi subsidiary. The production technology of strontium ferrite was studied and wet process of strontium ferrite pre-sintering material with anisotropic characteristic was determined. Products of Y30H-2 which meet the standard series of SJ/T10410-1993 were selected to be experimental products. In consideration of experiment and manufacture, the experimental procedure and mass manufacturing of strontium ferrite pre-sintering such as A, B, C and D produced at XiCi subsidiary was explained and discussed. Theexperiments were repeated for several times and its results was amended based on needs of experiment and mass manufacture. Combined with the analysis on the research results of hard ferrite in abroad, the relationship between solid diffusion reaction and particle size, temperature and time of pre-sintering as well as chemical activity of raw material that would affect the properties of pre-sinter material was analyzed. The experiment that would change the characteristic of pre-sintering material was conducted by using method of ion substitute. Molar ratio which improve the properties of strontium ferrite pre-sintering material was studied, the effect of nanometer composite additive was analyzed. Finally, we concluded that, manufacturing of hard ferrite pre-sintering material and magnet is depend upon both advanced technology and equipment as well as raw material with high purity we used, and small size particle, high activity, adequate and stable oxygen during sintering, narrow distribution of particle size during the second process of ball grinding, magnetic field with high strength are needed, reasonable sintering process, suitable sintering temperature and atmosphere are also important for sintering.