英文摘要 Subject: A Study on C02 Corrosion Mechanisms of pipeline steel Speciality: Oil&Gas Storage and Transportation Engineering Name:Huo Fuyong(signature)出生幽!g Instruct。r:He Guangyu(signatll托)丝垒鱼竺2生竺 AB STRACT The steel corrosion of carbon dioxide has caused huge loss in oil&gas storage and transportation C02 corrosion mechanisms、C02 corrosion actions and effect factors of pipelines steel are studied in simulating C02 corrosion hope this research could give some help on theory and experiment to C02 corrosion and its protection in the oil&gas field. First of all,by using weight·loss method,macroscopical and microcosmic photograph of steel slice,in the paper the author study some factors that affect C02 corrosion rate of pipeline steel,and then put forward some laws ofthe corrosion rate that is relate to temperature、C1。and C02 partial pressure et. Secondly,potentiodynamic polarization curve and EIS(Electrochemical Impedance Spectroscopy)techniques were used to analyze the influence of different effect factors of C02 corrosion on electrode reaction of A3 ,the author study the C02 corrosion mechanisms of XSO,and the relation of the mechanical properties of the corrosion film and C02 corrosion COUrse of X80 steel,and corresponding EIS models were established to interpret the effect of electrode reactions on EIS curve. In the C02 corrosion environment,the impact of C02 corrosion rate and electrode reaction of A3 steel from the corrosive effect factors anodic reactions are controlled by chemical activation 。adsorbs on the surface of XSO steel,and then e into FeOHads and FeOH基,Fe2十is found at reduction of H2C03 is the most important cathodic EIS curves change、Ⅳitll the scale covering the electrode capacitive arc in high frequency section extends but that contract in low frequency corrosion product film prevents XS0 steel from being further corroded. Finally,b