Patent number: 8801877
Abstract: An austenitic heat resistant alloy, which comprises by mass percent, C: over 0.02 to 0.15%, Si?2%, Mn?3%, P?0.03%, S?0.01%, Cr: 28 to 38%, Ni: over 40 to 60%, Co?20% (including 0%), W over 3 to 15%, Ti: 0.05 to 1.0%, Zr: 0.005 to 0.2%, Al: 0.01 to 0.3%, N?0.02%, and Mo<0.5%, with the balance being Fe and impurities, in which the following formulas (1) to (3) are satisfied has high creep rupture strength and high toughness after a long period of use at a high temperature, and further it is excellent in hot workability. This austenitic heat resistant alloy may contain a specific amount of one or more elements selected from Nb, V, Hf, B, Mg, Ca, Y, La, Ce, Nd, Sc, Ta, Re, Ir, Pd, Pt and Ag. P?3/{200(Ti+8.5×Zr)} . . . (1), 1.35×Cr?Ni+Co?1.85×Cr . . . (2), Al?1.5×Zr . . . (3).
Type:
Grant
Filed:
June 3, 2013
Date of Patent:
August 12, 2014
Assignee:
Nippon Steel & Sumitomo Metal Corporation
Inventors:
Hiroyuki Semba, Hirokazu Okada, Masaaki Igarashi