Patent ID: 6086948
Filing Date: 2000-07-11
Classification: C04B,G01N

Abstract:
A process for manufacturing a ceramic, diffusion-limiting layer using finely dispersed, ceramic powders, comprising providing an oxide ceramic powder having a BET specific surface area in a range of 5 to 50 m.sup.2 /g and a mean primary particle size of 20 to 450 nm, thermally pretreating a first portion of the powder at a temperature of about 800.degree. C. to 1150.degree. C. for a time sufficient to reduce its sintering activity, mixing the thermally pretreated powder first portion with the untreated portion of the powder, applying a layer of the mixed powder to a thermally-stable base, and firing the powder-coated base at a temperature in a range of about 1000.degree. C. to 1350.degree. C. to form the ceramic layer.