CASTABILITY, OPAQUE MASKING, AND PORCELAIN BONDING OF 17 PORCELAIN-FUSED-TO-METAL ALLOYS

Seventeen porcelain-fused-to-metal alloys, which represented a cross s ection of the various alloy types available, were evaluated for castab ility, opaque masking, and porcelain bond strength, The base metal all oys generally cast more completely than the noble alloys, with the pre sence of beryllium as an important factor for greater castability amon g the base metal alloys. Statistically significant differences were ob served in the ability of an opaque porcelain to mask the different all oy substrates but no systematic effect of alloy type was observed. Por celain bond testing revealed that nickel-chromium-beryllium alloys pro duced significantly better porcelain-metal bonds than nickel-chromium alloys without beryllium. In addition, it was found that palladium-cop per alloys produced significantly better bonds with porcelain than pal ladium-cobalt alloys.