Date of Award

Spring 2009

Document Type

Thesis - Restricted

Degree Name

Master of Science (MS)



First Advisor

Berzins, David W.

Second Advisor

Ziebert, Gerald J.

Third Advisor

Smithy, Thomas J.


Recently introduced to the market has been an entirely new subclass of casting alloy composition whereby palladium (- approximately 25 wt%) is added to traditional base metal alloys such as CoCr and NiCr, thereby raising their classification to that of a noble alloy. Little is known about this class of casting alloy, however, particularly its biocompatibility and corrosion properties. The objective of this study was to evaluate the corrosion properties of two new Co Pd Cr and one new NiPdCr alloy and compare them to traditional CoCr and NiCr alloys. The casting alloys investigated were: CoPdCr (Noble Crown NF, The Argen Corporation), IVOCoPdCr (Callisto CP+, Ivoclar Vivadent), NiPdCr (Noble Crown, Argen), CoCr (Argeloy N.P. Special, Argen), and NiCr (Argeloy N.P. Star, Argen). As-cast and oxidized cylinders were assessed electrochemically in phosphate buffered saline at 24°C. The open circuit potential (OCP) was monitored for 20 hrs followed by linear polarization and cyclic polarization tests. OCP at 20 hrs, polarization resistance (Rp), and corrosion current density (Icorr) were compared using Kruskal-Wallis and Mann-Whitney tests to determine whether differences existed between alloys and a t-test was used to examine the effect of oxidation on the corrosion properties. Eight and six specimens were evaluated in the as-cast and oxidized conditions, respectively. Results showed that the palladium containing alloys possessed a significantly greater open circuit potential, however, their polarization resistance was less and the corrosion current density was significantly greater than the traditional CoCr and Ni Cr. Additionally, a greater incidence of pitting was observed in the palladium containing alloys. Some differences were noted within alloys between the as-cast and oxidized conditions, but a major trend was not observed. Overall, the inclusion of palladium in CoCr and NiCr alloys had deleterious effects on the corrosion resistance of these alloys.



Restricted Access Item

Having trouble?