| 摘要 |
<p>Alkaline beta alumina is made by mixing alumina and carbonate powders, pref. Na2CO3 to obtain a predetermined ratio (R) = Al2O3/Na2O. The mixt. is heated in an open crucible, cooled, milled, then moulded and sintered. The novelty is that after moulding, the parts are coated with a sodium cpd. The parts are pref. dipped in, or sprayed with, a soln. or suspension contg. 30-350 g/l Na cpd., esp. the carbonate, aluminate or nitrate in water, alcohol or acetone. Moulding is pref. achieved by depositing the milled mixt. on a mandrel, followed by isostatic compression. Sintering is pref. at 1550-1700 degrees C. for 0.08-4 h, and pref. R = 5-11. The initial heating in an open crucible is pref. 1-5 h at 1150-1300 degrees C. The solid electrolyte is esp. for use in sodium-sulphur batteries. Prod. has consistant properties. A simple, inexpensive process for mfg. beta alumina contg. Na2O and possessing consistent properties.</p> |
