**4. Corrosion resistance of HNS**

The role of nitrogen in stainless steel with regards to the corrosion resistance has been previously reported within literature [Pleva, 1991], [Truman, 1988], [Pedrazzoli &Speidel, 1991], [Dong et al., 2003], [Mudali & Rai, 2004]. This chapter will review today´s knowledge and present own data; corrosion fatigue and high temperature corrosion will not be covered.
