Structure and Properties of Gas Nitrided Layers on Nanoflex Stainless Steel

Abstract

The paper presents results of research on nitrided layers on Sandvik NanoflexTMprecipitation hardened stainless steel. The influence of process parameters on nitriding kinetics and structure of the layers was investigated. The gas nitriding process was conducted in a mixture of ammonia 50% and products of its dissociation, as well as in 100% ammonia atmosphere at temperature range 400500°C and time between 2 and 8 h. The obtained diffusion layers were examined using the following methods: light and scanning electron microscopy, XRD phase analysis and EDS chemical analysis. Mechanical properties were tested with hardness measurements. It was found that kinetics depends on treatment temperature and nitrogen potential of the atmosphere. Moreover, treatment conditions affecting Sphase formation and expanded martensite in nitrided layers are discussed.