| Yttrium aluminum garnet (Y3AlsO12, YAG) is an important ceramic material with promising chemical stability, optical and mechanical properties. It can be used as refractory coating for electronic devices and as the host for rare-earth doped phosphors and for solid state laser. Recently, as an alternative of single crystal YAG, polycrystalline YAG ceramic was given much attention. At present, the synthesis methods of YAG powders include solid reaction, sol-gel processing and precipitation method,among in which co-precipitation method hae been widely used for being easy to control and simple process.In this dissertation, YAG powders were fabricated by using co-precipitation method from commercial yttrium oxide,aluminum sulfate,nitric acid and ammonium hydrocarbonate as the starting materials.We can improve the dispersion of powder calcined at1100℃for4hours by adding ammonium sulfate to the solution,the obtaining powder become a better dispersion with the the addition of ammonium sulfate increasing,when the addition of ammonium sulfate is0.03mol,the YAG powder own best dispersion,besides,it own a better sintering performance;However, changing the time of aging procedure have little effect on the dispersion of the YAG powder;Changing the titration rate can alter significantly the property of powder,the titration rate bigger and the quantity of transition phase less;we obtained powder at the titration rate of50ml/min which own a better sintering performance and whose main phase is YAQ its in-line transmittance is24%in the visable wavelength when the green body vacuum sintering at1650℃for5hours;incrasing the titration rate make the powder become smaller. When washed5times by de-ionized water,ethanol and acetone,it own a better sintering performance,but the powder own a better dispersion when it wased5times by de-ionized water, ethanol and ethanol which stearic acid dissolved in; When the amount of the addition of TEOS is0.5%, obtaining YAG powder own a better sintering performance. |
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