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On the steel surface defects in thermal processing in the field of materials processing has been a research hotspot. The oxide scale is one of the major defects of the steel surface quality, is one of the main reasons that led to its loss of quality, a direct impact on the rate of finished steel production in the metal. In this paper, the actual process of the Baotou Iron and Steel Group Rail Beam Plant heavy rail steel as the main research object U71Mn steel, the steel surface by the hot-rolled heating process oxidation burning more serious, in-depth study of the heating temperature, heating time, as well as the oxidizing atmosphere heavy rail slab surface oxidation. In order to clarify the oxidation kinetics of heavy rail steel, improve the finished product rate. Research experiment, using the desiccant method continuous weighing of the sample is calculated according to the experimental recording the weight of the unit area of ??the sample increased, drawing weight gain curves obtained billet surface oxidation and heating time, heating temperature between The kinetics of, and combined with the results of analysis of the content of oxidizing atmosphere on the oxidation loss under different atmosphere. Rapid warming, the the typical warming and slow warming the three heating system experiments, in air atmosphere, after 260min heated, billet in three heating system oxidation burning rate was 4.6%, 3.4% and 1.3%, respectively. Oxidation burning in the the simulated furnace atmosphere, billet were 3.1%, 1.7% and 0.6%, respectively. Oxidizing atmosphere had a significant effect on the amount of oxidation burning. , In an air atmosphere under a constant temperature of 900 to 1300 ° C, insulation test, the sample average oxidation rate was increased from 0.04 to 0.96 mg/cm2 · min, than 1100 ° C before the slow rate of oxidation, followed by significantly faster, 1100 ℃ rate change the inflection point; in simulated furnace atmosphere, the average oxidation rate is increased from 0.01 to 0.81mg/cm2 · min, the inflection point of the speed change at 1150 ° C. The oxidation rate of the oxidizing atmosphere under the respective temperature had a significant effect. Analog under the furnace atmosphere, each of the 1200 ° C and 1300 ° C, the weight gain of the insulation test curve an inflection point, weight gain before the curve is steeper in the inflection point, after a dense oxide layer suppresses the penetration of oxygen, the oxidation rate increases slowed, weight gain curve slows. The results for billet high temperature heating process, the exploration of the oxidation kinetics data support, provide a reliable theoretical basis for improvement of the heating process control for the actual production of the high-temperature oxidation of steel, energy saving and emission reduction of the iron and steel enterprises have important practical significance.
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