Modulo elastico della fase S in un acciaio 316 L kolsterizzato

Austenitic stainless steels are interesting materials for several industrial applications where corrosion resistance is a fundamental requirement [1]. However, their use is limited by low tribological behavior, which involves high friction and low wear resistance [2]. Conventional thermo-chemical surface treatments, such as carburizing and nitriding, improve surface hardness but drastically decrease corrosion resistance because treatment temperatures (generally higher than 550°C) induce the precipitation of Cr compounds depleting the surrounding matrix of Cr. To avoid the precipitation of Cr compounds it is necessary to operate at low temperature (< 470 °C). Low temperature heat treatments produce a surface layer of austenite supersaturated of interstitial elements (S phase), thermodynamically metastable [3]. An industrial carburizing process at low temperature is kolstering [4].....................................