| Theβ-SiC minute powder with had outstanding physical-chemistry performance is widely applied in area of high technology. Existing preparation technology has the question of craft backwardness, cost-high, low-grade products; small batch and so on, urgently needs the new technology to change this aspect. In the view of above-mentioned reasons, the new craft was studied that the massβ-SiC minute powder without broken was disposable synthesized by infinite-mini-heat sources furnace, using natural industrial raw material for the expensive industrial chemicals.The electric capability of quartz sand, petrol coke, anthracite coal and graphite raw materials and compound powder was studied. It was found that the electric capability differed from Ohm's law. The electrical resistivity of compound powder could represent two variations with the lifting of additional voltage.The processing parameter of different experimental raw material , different raw material gradation, different size of furnace, different supplying power and different supplying time and so on effects on the synthesizingβ-SiC minute powder were studied through the orthogonal law. The experiment result indicated that the productive rate ofβ-SiC minute powder synthesized by anthracite coal and graphite as carbon source is higher than petrol coke and graphite, and the phase of crystal is perfect; The less the size of raw materials, the less the grain size of product, especially the size of quartz grain; From the large-scale metaplasia, using the broad furnace. It is advantageous to temperature field disperses andβ-SiC crystal growth. Using the longer furnace, it is disadvantageous to temperature field disperses, but it is advantageous for enhancement quantity and rate; The electric power must be controlled properly after the successful firing 2 h, making it wavy vary, and enough holding time should be given; the productive rate is to 25.63 % , the grading of first quality ware is to 77.63 %,the total grading of first and second quality ware is to 98 %.The initial products of synthesizingβ-SiC minute powder by infinite-mini-heat sources furnace was graded carrying on Sole and Synthesis graduation methods, the experiment result indicated that the graduation output was quite low with simple screening processing, and the aqueous screening was efficiency higher than violates screening; A quite high graduation output which grain size of minute powder bigger than 20μm could get with the high-level condense-sift graduation; It's very even within every grade section which synthesizingβ-SiC minute powder was graded through free settled process method,under the condition of good subsidence medium, accurate pellet diameter , accurate settling rate and accurate settling time, the good grading effect would be obtained; Through the synthesis graduation method of screening firstly and free setting again grading, the graduation output was quite high than simple processing to the initial products, grain size of minute powder bigger than 20μm was easy concentrated with screening, and grain size of minute powder smaller than 20μm easy concentrated with free settling; Through the synthesis graduation method of free settling firstly and high-level condense-sift graduation again grading, the graduation output was quite high than simple processing to the initial products obviously, grain size of minute powder bigger than 20μm was concentrated well, and the concentration degree of one smaller than 20μm had been increased but not obviously.The initial synthesizingβ-SiC minute powder and grading product had been dead burned and pickled, Tested particle, XRD and SEM analysized. The result indicated that the content ofβ-SiC was enhanced from 90.20 % to 99.18 %, and the ones of other impurities were due to national standards. The content of free carbon was decreased from 7.60 % to 0.02 %.The ones of other impurities were due to national standards; the particle size of grading product was due to national standards and operation requirements; the crystal structure of product was 3C ofβ-SiC, but the growth of the crystal was not perfect, some crystal appeared semi-definite form. Simultaneously there were someβ-SiC whisker of 3C.
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