Abstract: Carbon—carbon composite parts are joined with minimum surface preparation. A reactive-bonding joint interlayer having thickness greater than 1 mil is formed of fine particles of carbide-forming metallic ingredients and carbon. The joint interlayer is sandwiched between the two carbon—carbon parts to be joined and the assembly is heated under a compressive pressure to a temperature sufficient to complete the bonding reaction. No special surface preparation is required for the carbon—carbon parts due to the nature of the reactive-bonding. The mechanical properties of the joint are assured by selecting the metal-carbon ingredients so that thermal expansion mismatch is minimized. Shear strength exhibited by the resulting joints is greater than the interlaminar shear strength of the carbon—carbon composite material.

Abstract: Carbon--carbon composite parts are joined with minimum surface preparation. A reactive-bonding joint interlayer having thickness greater than 1 mil is formed of fine particles of carbide-forming metallic ingredients and carbon. The joint interlayer is sandwiched between the two carbon--carbon parts to be joined and the assembly is heated under a compressive pressure to a temperature sufficient to complete the bonding reaction. No special surface preparation is required for the carbon--carbon parts due to the nature of the reactive-bonding. The mechanical properties of the joint are assured by selecting the metal-carbon ingredients so that thermal expansion mismatch is minimized. Shear strength exhibited by the resulting joints is greater than the interlaminar shear strength of the carbon--carbon composite material.

Abstract: A ceramic body based on barium and strontium titanates has a composition defined essentially by the formula Ba.sub.1-x Sr.sub.x TiO.sub.3, where x ranges from 0 to 1. The ceramic body is chemically and dimensionally stable in solid oxide fuel cell (SOFC) operation environments, which encounter oxidizing and reducing atmospheres at temperatures as high as 1,000.degree. C. In addition, the ceramic of which the body is comprised can be tailored to yield a ceramic in which the thermal expansion coefficient (CTE) is adjusted between 11.3.times.10.sup.-6 /.degree.C. and 12.4.times.10.sup.-6 /.degree.C. to match the CTE of the other SOFC materials, thereby avoiding the adverse effects of thermal stress. These features make the ceramic body especially suited for use as manifolds in SOFC stacks, or other non-electrical structural components, such as the inflow and outflow gas manifold materials, the stack housing, or other support structure or spacers in the stack, and the like.

Abstract: An anode/anode bonding material for anode to anode material bonding in SOFC stacks, and an anode/interconnect bonding material for anode material to interconnect material bonding in SOFC stacks are provided. The anode/anode bonding material comprises powders of reactive ingredients, nickel oxide and zirconium oxide as the major components. The anode/interconnect bonding material comprises powders of reactive ingredients, nickel oxide, zirconium oxide, cobalt oxide, calcium oxide or strontium oxide as the major components. The reactive ingredients are selected from the compounds of tungsten, tantalum, niobium, molybdenum, and titanium. During the bonding operation at subsintering temperatures of 1000.degree.-1300.degree. C. the bonding materials react with anode and/or interconnect material to provide strong and reliable anode to anode bonds and/or anode to interconnect bonds that have a bonding strength greater than one megapascal.