【摘要】 通过实验室内埋片实验研究了20#钢在近中性土壤中的腐蚀规律和机理。在三种不同土壤中埋片,对腐蚀后的试样腐蚀形貌和产物进行EDS和XRD分析,并测定了试样的腐蚀速率、自腐蚀电位以及极化曲线随时间的变化关系。结果表明:随着时间的延长,腐蚀速率是不断变化的;3种不同土壤中的钢试样经过相同的腐蚀时间后,1#和2#腐蚀最为严重,3#腐蚀程度稍轻;经过60d腐蚀后,能谱和射线分析其腐蚀产物主要是非晶质、Fe(OH)3和Fe2O3;不同时间和土壤的电位变化规律是不同的,与腐蚀速率变化规律是一致的。最后探讨了腐蚀机理,在近中性土壤中,低碳钢腐蚀的阴极过程主要是氧的还原,在阴极区域形成OH-离子,阳极过程是铁的氧化,氧化后的两价Fe2+发生水合作用,并转化为更稳定的产物Fe(OH)3和Fe2O3。更多还原

【Abstract】 Corrosion process and mechanism of 20# low-carbon steel in near-neutral in soil are studied by experiments of buried specimens in laboratory.In three kinds of soils,the corrosion features and products are analyzed by EDS and XRD,and the relation of corrosion rates,open-circuit potential and polarization curve with times are tested.The results indicated that corrosion rates changed incessantly along.On the condition of the same times,specimens and different soil samples,the corrosive degree of 1# and 2# specimens are serious,but 3# specimen is a little serious.The corrosion products are main non-crystalloid,Fe(OH)3 and Fe2O3.The change rules of different times and soils are different,and are accordant with that of corrosion rates.The corrosion mechanism is discussed,in near-neutral soils,oxygen is deoxidized and OH-ions are created in cathode area,iron is oxidized and the hydration of Fe2+ ions is created with water from soil in anode area,and Fe2+ are converted into more steady products Fe(OH)3 and Fe2O3.更多还原