A kind of steel for saline soil corrosion-resistant buried structure and its manufacturing method

Abstract

The invention discloses saline-soil-corrosion-resistant steel for buried structures and a manufacturing method of the steel. The steel contains 0.02% to 0.06% of C, 0.05% to 0.22% of Si, 0.30% to 1.20% of Mn; 0.010% to 0.030% Nb, 0.015% to 0.035% of Ti, 2.8% to 4.3% of Cr, 0.40% to 0.60% of Cu, 0.05% to 0.15% of Sb, 0.20% to 0.40% of Mo, 0.20% to 0.40% of Ni, 0.01% to 0.04% of Al, no more than 0.015% of P, no more than 0.005% of S, and the balance Fe and inevitable impurities. According to the manufacturing method, the casting blank off-production-line and slow cooling time is longer than or equal to 72 h, the heating temperature reaches 1230 DEG C to 1260 DEG C, the finishing rolling temperature of rough rolling reaches 1070 DEG C to 1120 DEG C, the initial rolling temperature of finish rolling reaches 1030 DEG C to 1080 DEG C, the finishing rolling temperature of finish rolling reaches 860 DEG C to 930 DEG C, the total reduction rate of finish rolling is higher than or equal to 65%,the cooling rate reaches 16 DEG C / s to 32 DEG C / s, and the steel coiling temperature reaches 720 DEG C to 780 DEG C. A steel plate made of the steel disclosed by the invention is high in toughness andsaline soil corrosion resistance.

Description

Technical field [0001] The invention belongs to the field of metal materials, and specifically relates to buried structural steel with good strength and toughness and soil corrosion resistance. Background technique [0002] Buried structures refer to buildings and structures built underground, such as bridges and culverts, pipe corridors, roadways, tunnels, and civil air defense projects. At present, the main building forms mainly include reinforced concrete structures and fabricated steel structures. Compared with Traditional cast-in-place concrete structure, fabricated steel structure has the advantages of low engineering cost, low construction difficulty, fast construction speed, anti-deformation ability and long durability, and the steel structure can be recycled, high utilization rate, fabricated steel structure In the future, it will gradually replace reinforced concrete structures and become the mainstream of future buried structure engineering. [0003] The steel used for ...

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Problems solved by technology

[0009] The patents disclosed in the above documents are all related to a grounding grid metal material for power transmission that is resistant to acidic soil corrosion. It is not high, so it cannot meet the requirements for the use of buried steel structure products such as bridges and culverts, pipe galleries, etc., and cannot meet the use in saline soil environments

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