A new low-cost corrosion-resistant rebar(HRB400 R) was designed and fabricated by chromium micro-alloying. The effects of Cr on the passivation and corrosion behavior of this rebar in the simulated concrete pore sol...A new low-cost corrosion-resistant rebar(HRB400 R) was designed and fabricated by chromium micro-alloying. The effects of Cr on the passivation and corrosion behavior of this rebar in the simulated concrete pore solutions were studied systematically, and its improved corrosion resistance was revealed. In the Cl--free saturated Ca(OH)_2 solution, the HRB400 R rebar presented nearly the same passive film and similar passivation ability compared to the common carbon steel rebar. In the long-term immersion corrosion test in the Cl--contained Ca(OH)_2 solution, the HRB400 R rebar presented improved corrosion resistance and obvious longer passivation-maintaining period. Micro-alloying of Cr element in the rebar matrix enhanced its corrosion resistance against Cl--attack and retarded the corrosion initiation in the matrix. In the alkaline Na Cl salt spraying test, the HRB400 R rebar also presented obviously lower mass-loss rate. The enrichment of Cr element in the rust layer improved its retardant effect to the penetration of aggressive medium, and decreased the corrosion propagation rate of the rebar.展开更多
基金Funded by the National Basic Research Program of China(973 Program,2015CB655100)the Natural Science Foundation of China(Nos.51308111 and 51278098)+5 种基金the Industry-UniversityResearch Cooperative Innovation Fund of Jiangsu Province(No.BY2013091)the Research Project of Science and Technology Development of China Railway Corporation(No.2014G004-F)the“Six Talent Peak”Project of Jiangsu Province(No.2014-XCL-023 and 2016-XCL-196)the China Postdoctoral Science Foundation(No.2013M531249)the Postdoctoral Science Foundation of Jiangsu Province of China(1202008C)the Applied Research Foundation of Nantong City(No.BK2013001)
文摘A new low-cost corrosion-resistant rebar(HRB400 R) was designed and fabricated by chromium micro-alloying. The effects of Cr on the passivation and corrosion behavior of this rebar in the simulated concrete pore solutions were studied systematically, and its improved corrosion resistance was revealed. In the Cl--free saturated Ca(OH)_2 solution, the HRB400 R rebar presented nearly the same passive film and similar passivation ability compared to the common carbon steel rebar. In the long-term immersion corrosion test in the Cl--contained Ca(OH)_2 solution, the HRB400 R rebar presented improved corrosion resistance and obvious longer passivation-maintaining period. Micro-alloying of Cr element in the rebar matrix enhanced its corrosion resistance against Cl--attack and retarded the corrosion initiation in the matrix. In the alkaline Na Cl salt spraying test, the HRB400 R rebar also presented obviously lower mass-loss rate. The enrichment of Cr element in the rust layer improved its retardant effect to the penetration of aggressive medium, and decreased the corrosion propagation rate of the rebar.