Nitrogen alloyed, Ni-free, austenitic stainless steels with more than 1 wt.-% nitrogen are a new group of alloys with promising properties. They exhibit a very interesting combination of high strength and toughness with a high corrosion resistance in various environments. This combination of properties makes this alloy not only suitable for fasteners but also for medical and dental implant applications. This work shows the influence of chromium, molybdenum and nitrogen on the corrosion resistance of Fe25Mn-alloys in media typical for the above mentioned applications. According to these results Fe25Mn-alloys with approximately 20 wt.% chromium about 3 wt.-% molybdenum and
approximately 1.3 wt.-% nitrogen have an excellent corrosion resistance in Ringer solution, artificial saliva and artificial sweat. The critical pitting temperature (CPT) of 61 °C and the critical crevice temperature (CCT) of 37 °C when tested according to ASTM G-48A were significantly higher than the well established AISI 316 L stainless steel.
Keywords: Ni-free austenitic stainless steel, nitrogen alloyed, corrosion resistance, Ringer solution, artificial saliva, artificial sweat