摘要 |
FIELD: metallurgy.SUBSTANCE: invention relates to metallurgy, namely to compositions of high-strength stainless steels used for production of seamless pipes for oil wells. Said steel contains following substances, in wt%: C: 0.05 or less, Si: 0.5 or less, Mn: 0.15 or more and 1.0 or less, Cr: 13.5 or more and 15.4 or less, Ni: 3.5 or more and 6.0 or less, Mo: 1.5 or more and 5.0 or less, Cu: 3.5 or less, W: 2.5 or less, N: 0.15 or less, Fe and unavoidable impurities - the rest. For the steel components the following requirement is to be followed: -5.9×(7.82+27C-0.91Si+0.21Mn-0.9Cr+Ni-1.1Mo-0.55W+0.2Cu+11N)≥13.0.EFFECT: steel has high resistance to sulphide corrosion cracking under stress.20 cl, 2 tbl |