STEEL FOR A CLASS R6 HIGH-STRENGTH AND HIGH-FLEXIBILITY MARINE MOORING CHAIN INTENDED FOR ANCHORING A FLOATING BODY WITH CATHODIC PROTECTION, AND MOORING CHAIN MADE THEREOF Russian patent published in 2021 - IPC C22C38/50 C21D8/06 

FIELD: metallurgy.

SUBSTANCE: invention relates to the field of metallurgy, namely to a class R6 steel high-strength and high-flexibility marine mooring chain intended for anchoring a floating body with cathodic protection. The steel chain has a chemical composition containing, in % wt.: C 0.21 to 0.23, N 0.018 to 0.023, P 0.005 to 0.025, S≤0.005, Si 0.15 to 0.35, Mn 0.20 to 0.40, Cr 1.40 to 2.60, Ni 0.80 to 3.20, Mo 0.35 to 0.75, Cu≤0.50, Al≤0.02, Ti≤0.005, V 0.04 to 0.12, Nb 0.02 to 0.05, Ca 0.0005 to 0.004, O≤0.0015, H≤0.00015, wherein the remainder constitutes Fe and unavoidable impurities. The contents of the components of the steel satisfy the following dependencies: 0.22 ≤ (C+N) ≤ 0.26, 3.4 ≤ (Si+Mn+Cr+Ni+Mo+Cu) ≤ 6.8 and 0.065 ≤ (Ti+Al+Nb+V) ≤ 0.194.

EFFECT: required mechanical properties and corrosion resistance are provided under the conditions of operaton in seawater.

12 cl, 6 dwg, 4 tbl, 4 ex