| 摘要 |
PURPOSE: A preparation method of pyroelectric ceramic powder for uncooled infrared sensor by a sol-gel method is provided, which offers homogeneity, small particles and low calcination temperature, and decreases pore volume and pore size in sintered products to improve dielectric and pyroelectric properties. CONSTITUTION: The pyroelectric ceramic powder for uncooled infrared sensor is expressed by the formula of (BaaSrbCac)(1-y)Dy AxTi(1-x)Oa, wherein D is Y2O3, La2O3 or Dy2O3, A is MnCO3, 55<=a<=70, 25<=b<= 40, 0<=c<=15, a+b+c=100 mol%, 0<=z<=0.2 mol%, and 0<=z<=1.5 mol%. The pyroelectric ceramics are produced by the following steps of: pouring barium acetate, strontium acetate and calcium acetate into a reactor filled with 12-15M of acetic acid; flowing N2 gas into a reactor and heating to 110-120deg.C to remove some of moisture and acetic acid; lowering the temperature of the reactor to 60-80deg.C; adding a mixture of Ti-isopropoxide and 2-methoxy ethanol; mixing reactants at 60-80deg.C for 40-60min; adding 2-methoxy ethanol and pure water to a (BaSrCa)TiO3 solution in the reactor for gelation; drying at 100deg.C; calcining at 750deg.C; ball-milling calcined powder in ethanol medium to be a size of 0.1micrometer; ultrasonic forming and sintering.
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