Affiliations: Prosthodontics, Department of Restorative Dentistry, Indiana University School of Dentistry, Indianapolis, IN, USA | Operative Dentistry, Department of Restorative Dentistry, Indiana University School of Dentistry, Indianapolis, IN, USA | Dental Materials Research Laboratory, Department of Restorative Dentistry, Indiana University School of Dentistry, Indianapolis, IN, USA
Note: [] Corresponding author: Professor Yoshiki Oshida, Dental Materials Research Laboratory, Department of Restorative Dentistry, Indiana University School of Dentistry, 1121 West Michigan Street, Indianapolis, IN 46202‐5186, USA. Tel.: +1 317 274 3725; Fax: +1 317 274 2415; E‐mail: yoshida@iusd.iupui.edu.
Abstract: Dual‐phase stainless steels have been developed in order to reduce the nickel content, which is potentially responsible to an allergic reaction when these steels are used as medical or dental applications. In this study, two different dual‐phase stainless steels (2205 and Z100) were electrochemically tested to evaluate their corrosion resistance in three corrosive solutions (i.e., synthetic saliva, 0.9% NaCl solution, and Ringer solution). Particularly, an attempt was made to correlate the corrosion resistance to a metallographic parameter, which is, in this study, the alpha/gamma phase ratio. It was concluded that (1) type 2205 stainless steel exhibited excellent corrosion resistance in all three corrosion media; however 2205 stainless steel decreases its corrosion resistance by increasing chloride concentration in tested electrolytes from synthetic saliva through 0.9% NaCl solution to Ringer solution. (2) X‐ray diffraction analysis indicated that the α/γ phase ratio of 2205 (1.735) was higher than that of Z100 (0.905). As a result, it is suggested that by increasing the α/γ phase ratio the material shows more corrosion‐prone behavior when being subjected to a hostile environment containing higher chloride ion concentration.
