Abstract: Effects of quenching temperature and nitrogen content on microstructure, mechanical properties and corrosion resistance of 20Cr13,20Cr13N and 20Cr13HN steels were investigated. The results show that with the increase of nitrogen content, the nitrides pinning effect is enhanced, the microstructure is refined obviously, the yield strength, tensile strength and Vickers hardness increase, but the elongation decreases. At the same quenching temperature and cooling rate, the Vickers hardness increases under the action of solid solution, precipitation and phase transformation strengthening. With the increase of cooling rate, the driving force of phase transformation increases, the lath martensite gradually changes to fine cryptocrystalline martensite and the hardness increases. The corrosion property and pitting potential increase with the increase of nitrogen content.

Key words: martensite stainless steel, quenching temperature, nitrogen content, microstructure, hardness, corrosion resistance