| As an important high-temperature structural materials, ZrC has varieties of excellent physical and chemical properties, such as high melting point(3550 ?), hardness(25 GPa), conductivity, strong wear resistance and corrosion resistance. These unique properties make ZrC a promising and potential reinforcement ceramic material for practical applications as diffusion barrier in nuclear industry, cutting tools, wear resistant parts, catalyst, electrical field emitter tips and arrays, reinforced-particles in the composites, and so on. Because the agglomeration may seriously affect and even make micro and nano powders lose their excellent performance, in order to achieve micro and nano ZrC powders used in industry, this paper studies the suspending and dispersing of ZrC powder in the polymer solvent. A high solid content(30wt%), prolonged stable dispersion of zirconium carbide-phenolic resin suspension has been prepared in this work.In this paper for the ZrO2-Mg-C12H22O11 system, by adjusting the ratio of endothermic reaction and exothermic reactions in entire reaction system, controled effectively of the reaction temperature of the system, to dilute the chemical reaction of SHS reaction purposes. The effects of dilution ratio, raw materials of the milling process to the final product for morphology and chemical compositions were investigated. The results show that the ball milling pretreatment process was essential for effective production of high quality ZrC nano-powders. The raw materials without ball milling process, neither high nor low proportion of an endothermic reaction, the reaction system are not completing, there are other impurities except of ZrC, such as ZrO2 and Zr2 O. When the raw materials with planetary ball milling and the proportion of endothermic reaction is 40%, high purity ZrC powders are synthesized from reaction system with mean particle size of 60nm?Production of the oxidation process begans about 200 ?, described experimental micro-nano ZrC powder synthesized at a low temperature is more susceptible to oxidation, maybe ZrC powders have a smaller particle diameter and higher surface activity energy.This paper studies the preparation of ZrC-PF suspension with fine mobility and static stability,exploring the effects of choice and compounding ratio of organic solvent, dispersant, ZrC-PF suspension preparation process, pretreatment process of ZrC powders on the stability and mobility of the suspension. When phenolic resin, acetone, dispersant, pretreated ZrC powders mass ratio for 1:2:0.1~0.3:1.42, ZrC-PF suspension with fine static stability and liquidity is made in this work. The viscosity of ZrC-PF suspension is 200mPa?s~800 mPa?s. The best pretreatment process of Zr C powder: ZrC powders was mixed with a mass concentration of 35% concentrated hydrochloric acid by mass ratio of 1:5, stirred at room temperature for 10 h, then suction filtered, the filter cake was washed with de-ionized water until neutral, the resulting pretreated powders was triturated and dried in a mortar with organic solvent.By using suspension static pressure measuring instrument, the relationship between ZrC-PF suspension sentinel standing time and hydrostatic pressure was studied. The ZrC-PF suspension, which was produced by optimized process, stand for 24 hours, the ratio of the pressure variations in upper liquid layer is 20% or less, indicating ZrC-PF suspension can maintain good stability, no significant sedimentation occurred. |
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