Mechanical properties and microstructural analysis of an AgPd alloy cast under different temperatures

ABSTRACT

The metal restorations are used in Dentistry a long time ago. Nowadays we have resources that can get casting moreaccurate, with new material and equipments and techniques more precise. The purpose of this study was to evaluate themetallurgical and mechanical aspects of the AgPd dental alloy when it was submitted to different casting temperatures. Itwas used 30 specimens, divided in three groups (n=10): a) control group (no cast); b) casting temperature in accordancewith the manufacturesÆ instructions (T1); b) casting temperature above manufacturesï instructions (like a torch) (T2). Itwas evaluated chemical and metallographic aspects, mechanical properties and Vickers hardness. The results showed amicrostructure similar to T1 and T2 conditions, but with greater amount of light phase and particles in this last one. It wasobserved that the rupture tensile strength for the T1 condition was greater than the T2. The alloy in the no cast conditionpresented greater hardness but there was no statistically significant difference between T1 and T2. Supporting by themetallographic and mechanical results, it may predict that when elevated temperatures was used, above manufactureïsrecommendations, it can occur failures in the prosthesis, like porosities, fissures or cracks.