Abstract: An electrical device (1) in which an element (7) composed of a conductive polymer composition is positioned in contact with the first surface of a metal electrode (3), the first surface having a center line average roughness Ra and a reflection density RD, the product Ra times RD being at least 0.06 &mgr;m, with an adhesion promoting layer positioned between the first surface of the metal electrode and the polymer element. The conductive polymer composition preferably exhibits PTC behavior. In other aspects, electrical devices using more than one adhesion promoting layer (11), and electrical devices using an adhesion promoting layer in combination with a crosslinking agent (9) are provided. Other embodiments include electrical devices with metal electrodes made by pulse plating processes, and metal electrodes made by electrodeposition under diffusion-limited conditions. The electrical devices may be circuit protection devices and have improved electrical and physical properties.

Abstract: A method of making varistor chips is disclosed. A workpiece of varistor material is sliced into slices of varistor material. The slices are in turn diced to make the varistor chips. The chips are etched in an etchant such as dilute citric acid to remove from their surfaces varistor material damaged during the slicing and/or dicing operations. Otherwise, the damaged varistor material adversely affects the leakage current characteristics of the varistor chips.

Abstract: A method for making a high strength porcelain for use as an insulator or a structural ceramic, comprising:A) forming a mixture comprising alumina, clay and a fluxing material;B) forming the mixture into a shaped article; andC) firing the shaped article.

Abstract: A porcelain having 9 to 55% by weight of SiO.sub.2, 36 to 87% by weight of Al.sub.2 O.sub.3, 0 to 2.0% by weight of Fe.sub.2 O.sub.3, 0 to 1.0% by weight of TiO.sub.2, 0 to 0.5% by weight of CaO, 0 to 0.5% by weight of MgO, 1.0 to 4.0% by weight of K.sub.2 O and Na.sub.2 O combined, and 0.25 to 25.0% by weight of bismuth oxide is disclosed. The porcelain has unexpectedly high unglazed bending strength and may be used for dielectric and structural applications.

Abstract: A metal oxide dielectric dense body, comprising (I) grains having a predominant crystalline phase (a) a primary metal oxide selected from the group consisting of silicon and magnesium oxide and (b) optionally a secondary metal oxide selected from the group consisting of aluminum and zinc oxide and (II) between about 1 and about 20 atom % bismuth, vanadium, or boron oxide or combination thereof, discontinuously located at the boundaries of the crystalline grains or as inclusions in the crystalline grains, the atom %'s based on the total atoms of bismuth, vanadium, boron, silicon, magnesium, aluminum, and zinc. The dense body has a density which is at least 95% of theoretical.

Abstract: A metal oxide dielectric dense body, comprising (I) grains having a predominant crystalline phase (a) a primary metal oxide selected from the group consisting of silicon and magnesium oxide and (b) optionally a secondary metal oxide selected from the group consisting of aluminum and zinc oxide and (II) between about 1 and about 20 atom % bismuth, vanadium, or boron oxide or combinations thereof, discontinuously located at the boundaries of the crystalline grains or as inclusions in the crystalline grains, the atom %'s based on the total atoms of bismuth, vanadium, boron, silicon, magnesium, aluminum, and zinc. The dense body has a density which is at least 95% of theoretical.

Abstract: A metal oxide dielectric dense body, comprising (I) grains having a predominant crystalline phase (a) a primary metal oxide selected from the group consisting of silicon and magnesium oxide and (b) optionally a secondary metal oxide selected from the group consisting of aluminum and zinc oxide and (II) between about 1 and about 20 atom % bismuth, vanadium, or boron oxide or combinations thereof, discontinuously located at the boundaries of the crystalline grains or as inclusions in the crystalline grains, the atom %'s based on the total atoms of bismuth, vanadium, boron, silicon, magnesium, aluminum, and zinc. The dense body has a density which is at least 95% of theoretical.