Abstract
To develop porcelain-facing alloys for conical double-crown telescopic prosthesis, several alloys were manufactured by adding 0.5%, 1.0%, 1.5% Zr to a Co-Cr alloy containing 2% titanium.
Physical and mechanical properties and the bond strength of these alloys were examined to investigate the optimal amount.
The following results were obtained:
1. Oxidation at the melting point of the alloy were reduced by the addition of Zr.
2. The value of Vickers hardness were reduced by the addition of Zr.
3. The value of contraverse strength and elastic constant were reduced by the addition of Zr.
4. The bond strength was increased by the addition of 0.5% Zr, and the optical value was obtained at 1, 050° under reduced pressure.
5. The optimal additional amount was 0.5% for porcelain-facing alloys for conical double-crown telescopic prosthesis.
6. The bond strength was increased by the addition of Zr, because the form of Cr2Co3and CoO at the oxide layer were restrained.
