A method for joining together two or more ceramic and/or metal parts by providing a braze consisting of a mixture of copper oxide, silver, and ceramic particulate. The braze is placed upon the surfaces of the parts, which are then held together for sufficient time and at a sufficient temperature to cause the braze to form a bond between the parts. The addition of the ceramic particulate increases the viscosity of the braze, decreasing squeeze out, decreasing the formation of air pockets, decreases the formation of brittle phases by providing nucleation sites and increases the flexural strength of the joint.
GOVERNMENT RIGHTS STATEMENT
 The invention was made with Government support under Contract DE-AC0676RLO 1830, awarded by the U.S. Department of Energy. The Government has certain rights in the invention.