Preparation Of Nanosized MgO-PSZ Powder

ZrO2is the raw material for refractory, high-temperature structural material and electronic material due to its excellent properties. Oxygen sensors made of ZrO2(MgO) solid electrolyte are widely used in steel industry, which have significance of controlling the smelting progress as well as improving the quality of steel products. This paper study the way to optimize preparation of ZrO2(MgO) solid electrolyte. The MgO-PSZ powder was, with composition of8mol%MgO, and92mol%ZrO2, prepared by chemical coprecipitation. The effects of filter methods, Zr4+concentration, drying methods, dispersant, solvent and precipitation agent on the particle size, morphology and crystal type were investigated. The following conclusions were obtained.(1) Filtering methods have no effect on the phase and grain size of the powder. However, the powder prepared by centrifugal filter have finer particles and better dispersion than by suction filter.(2) Low temperature oven drying could obtain powder with fine properties.(3) With Zr4+ion concentration increasing, particles coarsened. Smaller particle size could be obtained when the concentration of Zr4+solution was0.5mol/L.(4) Addition of suitable amount of polyethylene glycol (PEG) could effectively weaken the agglomeration of powders, and its role was more obviously than ethanol.(5) The power with small particles, good dispersion and a small amount of agglomeration could be obtained when ethanol and butanol (volume ratio1:1) as solvent solvent for precipitating and washing(6) As for precipitation agent, with deionized water as solvent, powder with good dispersion could be prepared while the solution of NH4HCO3(0.5mol/L) or (NH4)2CO3(0.5mol/L) was added to the ammonia. When it comes to the the mixture solution of ethanol and butanol (volume ratio1:1), the dispersion could be improved as well as the particle size and grain size.(7) The powder has good sintering properties when a mixture of ammonia and 0.5mol/L carbonate ammonia or ammonium bicarbonate for the precipitation agent system. In particular, the powder obtained by adding0.5mol/L ammonium bicarbonate can reach the largest sintered density and a minimum of porosity.