Tensile strength determination of the interface between porcelain fused to gold

A method of testing the tensile strength of the porcelain–gold bond has been developed. Tensile strengths of the bond are improved primarily by the formation of an oxide layer on the gold before baking the porcelain and not by the degree of gross surface roughness. The oxide layer may act either as a transition ayer or it may create microsurface roughness. The gross surface roughness probably complicates the wetting action of the porcelain on the gold. Whether the actual bond is of a chemical nature, physical nature, or both, remains uncertain.