HIGH-NITROGEN AUSTENITIC STAINLESS STEELS WITH GOOD ECO-INDEX AND EXCELLENT PITTING CORROSION RESISTANCE, AND FABRICATION METHODS THEREOF

摘要

PURPOSE: High-nitrogen austenite stainless steel with high balance of strength and ductility and high pitting corrosion resistance and a manufacturing method thereof are provided to obtain a stable austenite single phase by maintaining a high content of N, 0.5wt.% or greater. CONSTITUTION: High-nitrogen austenite stainless steel comprises Cr(Chromium) of 17.0-19.0wt.%, Mn(Manganese) of 11.0-21.0wt.%, Ni of 5.0wt.% or less, Mo(Molybdenum) of 2.5-3.5wt.%, N of 0.5-1.2wt.%, and Fe(Iron) and inevitable impurities of the remaining amount. The inevitable impurities include C(Carbon) of 0.03wt.% or less and Si(Silicon) of 0.25wt.% or less. The austenite stainless steel satisfies the relation of 5.0<=Ni+25×N+0.5×Mn-Cr-1.5×Mo<=14.0.