Abstract
New dental gold alloys were prepared on the basis of the gold alloy 80wt% Au-20wt% Cu by the additions of 1wt%, 2wt%, and 3wt% cobalt. The properties of Vickers hardness, tensile strength, elongation, SEM fractographs, metallography, XRD and corrosion resistance were investigated in comparison with the commercial dental gold alloy of ADA standard Type IV for both after-solution treatment and age-hardening treatment. After age-hardening treatment, the mechanical properties were greatly improved by the addition of Co and become nearly equivalent to Type IV in 2wt% Co and 3wt% Co alloys. ICP analysis after immersion in simulated body fluid showed that the dissolution level of Cu and Co was about the same as commercial gold and Co-Cr alloys. These results indicate that Au-Cu-Co dental alloys have properties equivalent to Type IV gold alloys.
