Methoden zur Pulverpräparation für technische Keramiken

Abstract

Methoden zur Pulverpraparation fur technische Keramiken Ilans-Peter Siiicht*, Dieter Vbltzke, l'horrias Jt'icller il.lctrtin-Luther-Univcrsitat Halle-\Tittenberg, Sektion Chemie, 0-4010 Hallc Suiiimar y Ceranzic muterials hrwe been known f o r several thousands of yews, but a.n intensive research in the last two decades was leading to the advanced materials which are becoming established in todays technology and which are expected to form the backbone of developments to the next century. Thc properties of the ,final ceram ics are greatly predeterrrhilaated by the characteristics of the stnrting powder materials. This situation stimulated the increase of studies on preparation of taylor made powders with regard to purity, ho?nogeneity, reactivity, grain size and grain size distrihution. Starting with the classical solid state reaction (i detailed review i s given of wet chew icd preparation techniques for perovskite type materials. Briefly some physical methods of powder preparation are .tnentioned. Furthermore importcint processes accompanying the prepuratiova as drying, control of agglomeration behuviour and powder characterization are discussed, respectively. _ -Ri '-' X Eine sehr interessante und wichtigc Frege in diesem Zusammenhang ist die Untersuchung quentitativer Beziehungen zwischen der Kristallstruktur und den physikalischen Eigenschaften. Bekanntlich bewirken haufig sehr kleine Veranderungen im Kristall mit O , T~ < t < t,o.