An industrial atmospheric corrosion resistant rebar and a production method thereof

Abstract

An industrial atmospheric corrosion resistant rebar and a production method thereof belong to the technical field of steel for corrosion resistant rebars. The rebar comprises the following chemical components, by weight C 0.14-0 .19%, Si 0.4-0 .6%, Mn 0.8-1 .2%, P 0.05-0. 08%, S <0.005%, V 0.03-0 .07%, Cu 0.32-0 .45%, Cr 0.4-0 .6%, and the balance Fe. A process of primary melting in a converter + refining in an LF furnace + continuous casting + high temperature open rolling + medium and low temperature finish rolling + grading cooling is adopted in the production method to obtain high-strength industrial atmospheric corrosion resistant steel. Through a rational component design and establishment of reasonable continuous casting and rolling process parameters to suppress surface enrichment of single-phase Cu, so an economical non-Ni Cu-P series corrosion resistant steel is developed. According to the invention, the advantages are as follows: by employing existing steel production equipment, surface quality problems of ingot blanks and mill bars of non-Ni corrosion resistant steel are solved and ultrafine grain structures are obtained, thus improving corrosion resistance, and meeting performance requirements on industrial atmospheric corrosion resistant rebars at economical costs, having a very broad application space in China.

Description

technical field [0001] The invention belongs to the technical field of corrosion-resistant building steel, in particular to a steel bar resistant to industrial atmospheric corrosion and a production method thereof. Background technique [0002] The premature failure of reinforced concrete structures caused by the corrosion of steel bars has become a major disaster that has been widely concerned by countries in the century. According to reports in the United States, in terms of bridges alone, more than half of the 575,000 reinforced concrete bridges have steel corrosion damage, and the repair cost of reinforced concrete corrosion damage costs 250 billion U.S. dollars a year, of which the bridge repair cost is 155 billion U.S. dollars. 4 times the initial construction cost of the bridge. [0003] In our country, steel bars are susceptible to corrosion, which affects the gripping force of reinforced concrete, reduces the performance and service life of the building, and increa...

AI Technical Summary

Problems solved by technology

[0006] 1) Domestic manufacturers have developed 2205 stainless steel bars and have been used in a very small amount in major national projects. The main alloy is 22.5%Cr-5.8%Ni-3.0%Mo, and stainless steel bars have excellent corrosion resistance. However, the cost of the alloy is extremely high, which limits its wide-scale promotion and use, and the demand for corrosion-resistant steel bars in my country is huge, and the resources of Ni and Cr in my country are not abundant, and there is no sustainability

[0007] 2) In the U.S. market, the U.S. MMFX company has developed and widely promoted the application of low-carbon high-Cr-N corrosion-resistant steel bars, which contain about 9% Cr and 200-400ppm N. The alloy cost is significantly lower than that of stainless steel bars. Tensite + lath martensite + retained austenite structure, excellent corrosion resistance, but the cost of low-carbon Cr-iron alloy per ton of steel is still close to 3,000 yuan

[0009] 4) There is still a small amount of research and development of Cu-Mn synergistic corrosion-resistant steel in China. The cost of the alloy is low, but the corrosion resistance is not satisfactory

Images