摘要
Carbon addition into martensitic stainless steel for making kitchen knives is conventionally adopted to gain high enough hardness.The corrosion resistance,however,is dramatically reduced with carbon addition.More importantly,the amount of some hazardous elements released for such type of martensitic stainless steels in contact with food might be higher than the upper limit for the articles in contact with food according to the standards being applied worldwide.Accordingly,a new ecologically friendly nitrogen alloyed martensitic stainless steel has been developed.The nitrogen addition for substituting carbon in the martensitic stainless steel can increase the hardness and the corrosion resistance simultaneously.Of more importance is its much better resistance against the release of the hazardous elements than the conventional carbon alloyed steel.This paper summarizes the physical metallurgy,the processing technology and the microstructure and the mechanical properties of the developed ecologically friendly nitrogen alloyed martensitic stainless steel.