Creep-strength enhanced austenitic stainless steels for high temperature structural materials and preparing method of the same

摘要

Provided are an advanced austenitic stainless steel with improved creep strength with high aluminum and titanium content, maximally improving the phase stability of γ'-Ni3(Al,Ti), and a method for manufacturing the same. The advanced austenitic stainless steel with improved creep strength according to an embodiment is iron (Fe) 36-49 wt%, nickel (Ni) 30-35 wt%, chromium (Cr) 14-18 wt%, aluminum (Al) It contains 4-6 wt%, titanium (Ti) 2-4 wt%, and niobium (Nb) 0.5-1.5 wt%, has an austenitic matrix structure, and the B2-NiAl phase between dendrites in the austenitic matrix structure is different. have. The advanced austenitic stainless steel with improved creep strength according to an embodiment exhibits an improved creep resistance with a creep rupture time of 600 hours or more in an environment of 750 degrees Celsius and 150 MPa.