Copper precipitate formation by internal reduction of (Ni,Cu)O

Abstract

Studies of the structure and properties of metal-ceramic interfaces have recently become of considerable interest due to the need for a basic understanding of ceramic-metal bonds, which are increasingly used in ceramic technology. A convenient means to experimentally study such interfaces is by internal oxidation of metal alloys or by the internal reduction of oxide systems. In this manner low-energy interface structures are expected to be formed which provides a means for testing theoretical concepts regarding the energetics and structure of heterophase interfaces.NiO-10at% Cu-doped polycrystalline boules were grown by the Verneuil process in an arc-image furnace. The reagent-grade starting powder from which the boule was grown was produced by the amorphous citrate process. The polycrystalline boule was cut into slices which were annealed separately at 900, 950, 1000, 1100, 1300 and 1500°C under CO2/CO atmospheres for 3 to 6 days.