Properties of cobalt-chromium metal ceramic alloys after heat treatment.

A comparison of mechanical properties of seven metal ceramic alloys in as-cast and heat-treated conditions resulted in significant differences. The alloys that were tested included seven cobalt-chromium metal ceramic alloys. Mechanical properties include strength, elongation, modulus of elasticity, and microhardness. Twenty-four tensile bars were cast for each alloy. Twelve of the 24 bars for each alloy were randomly selected for heat treatment with the Ceramco technique. Results indicated that the tested alloys had similar mechanical property values as a group in both the as-cast and the heat-treated conditions. The heat treatment had little effect on the cobalt-chromium alloys, although several did become significantly harder. In either condition, the cobalt-chromium alloys showed a high value of strength, a low percent of elongation, a high modulus of elasticity, and a high value of hardness. The high value of hardness and the low percent of elongation would make these alloys difficult to handle clinically.