Titanium-microalloyed economical high-strength weathering steel and production method thereof

Abstract

The invention provides titanium-microalloyed economical high-strength weathering steel and a production method thereof. The titanium-microalloyed economical high-strength weathering steel comprises 0.08%-0.14% of C, 0.25%-0.50% of Si, 0.40%-0.70% of Mn, no more than 0.012% of P, no more than 0.005% of S, 0.40%-0.70% of Cr, 0.02%-0.07% of Ni, 0.20%-0.40% of Cu, 0.020%-0.045% of Alt, 0.025%-0.050% of Ti, no more than 0.0040% of N, and the balance Fe and inevitable impurities. According to the titanium-microalloyed economical high-strength weathering steel and the production method thereof, the low-Mn and Ti-microalloyed design is adopted and is combined with the controlled rolling and cooling process, so that the high-strength weathering steel has excellent comprehensive mechanical properties, welding performance and forming performance.

Description

technical field [0001] The invention belongs to the field of alloy smelting, and in particular relates to a titanium microalloyed economical high-strength weathering steel and a production method thereof. Background technique [0002] According to statistics, the annual economic losses caused by metal corrosion in my country account for about 3%-5% of the national GDP. Due to its excellent atmospheric corrosion resistance, weathering steel can slow down the corrosion rate of steel materials in the atmospheric environment. It is widely used in steel structures exposed to outdoor atmospheric environments for a long time, such as containers, railway vehicles, bridges, towers, and cable trays. application. Weathering steel mainly forms a dense protective rust layer between the rust layer and the substrate by adding alloy elements such as Cu, P, Cr, Ni, etc., thereby blocking the penetration of corrosive media into the steel substrate and slowing down the corrosion of the metal ...

AI Technical Summary

Problems solved by technology

The yield strength of the steel is ≥345MPa, and the microalloying element Nb is added, and the production cost is relatively high

And the P content is high, it is easy to form a high P segregation zone, which reduces the low temperature impact toughness and welding performance of the steel

[0009] The low-cost weathering steel involved in the above four patents has a high P content on the one hand, which reduces low-temperature impact toughness and welding performance, and on the other hand has low strength, which is not conducive to the development of lightweight and thinning steel structures.

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