Preparation Of Ceramic Slurry Dispersion Stability And Slip Casting

High-performance Recrystallized Silicon Carbide (R-SiC) material, has excellent high temperature mechanical properties, good resistance to oxidation and erosion resistance ability and high intensity, can be applied to various hollow high temperature structural materials. But the current domestic production of R-SiC products has certain disparity in using temperature, strength and service life etc production performance with foreign. Therefore, Improving the properties of materials and molding process, for high-performance R-SiC products in the research is necessary. In R-SiC ceramics sintering process, the high temperature liquid has no foundation, products of the green body density has been dimension by forming decision.Improving R-SiC products performance is key to improve the density of given photo-cell and forming.This study adopts SiC as the main raw material, through SiC powder surface modification—pollution free SiC/PMMA composite mold preparation—centrifugal pressure grouting molding obtain green body and high density. This paper mainly studies the modification process to SiC powder dispersing capability and the impaction of slurry rheological properties determine, the influence of the change of pulp viscosity with the green body and density defoaming craft; Influenced SiC/PMMA compound mould aperture, porosity and intensity factor; Discusses the mould structure, centrifugal rate and moulding pressure grouting molding of centrifugal pressure influence, determine the optimal process parameters.Experimental results show that: when silane coupling agent YDH560 and homemade modified protectants A-3 to SiC micro powder for double coating modification around, powder Zeta potential absolute maximum from 41.2 mV raise to 62.5mV,after 12h,70vol%mud in low-speed stir paste viscosity increment from630mPa·s reduce to 230mPa·s, green body density is reached 2.69 g/cm3. 40vol%10μmSiC, 10vol% PMMA in 65℃composite paste made curing, flexural strength for 8MPa, average aperture 3.5μm, porosity 44% of SiC/PMMA compound mould. Centrifugal speed 200 rpm, moulding pressure 0.8 MPa,60s prototyping time, under the condition of in vivo made plastic billet surface density differences< 0.05, centrifugal pressure grouting billet bulk density than casts grouting molding improve 1.5%, achieve 2.73 g/cm3.Research shows that, high active SiC micro powder surface modification of grafted with things off in alkaline environment is the cause of high solid content slurry viscosity changes with stirring time prolongs the main reason, slurry has a direct effect on the defoaming green body and density and stability; SiC decreases and the content of solid particle increases the paste viscosity, lower mould aperture and hydrophilic monomer concentration, the PMMA and water content decided to mould and porosity; Centrifugal speed and moulding pressure, joint action affecting the molding time, billet body structure and molding density.