关键词: 腐蚀产物膜, 二氧化碳腐蚀, 温度, 膜厚, 晶粒, 形貌结构, 高温高压釜, 扫描电镜

Abstract: The corrosion process of three kinds of tubing steels in the environment of carbon dioxide was simulated with high-temperature and high-pressure autoclave.The effects of temperature on the scale thickness of corrosion product and crystal average grain size of the corrosion products were analyzed using the scanning electron microscope.The analysis results show that the scales of corrosion products from the three kinds of steels have double-layer structures in the cross sections.The maximum variation of average thickness of the scales for the three kinds of steels appeared at 120℃.However,the minimum variation of the average thickness of scales for the steels of N80 and J55 appeared at 160℃,for steel P110 at 180℃.The variations of the average grain sized of scales with temperature for the three steels exhibited a peak and a valley,respectivelyl.The temperatures corresponding to the peaks of three steels were all at 120℃,and the temperature of valleys for N80 and J55 were at 160℃ and for P110 at 180℃.The crystal grain sizes for different materials varied,but the temperature corresponding to the peak or valley of the average thickness of scales was the same with that corresponding to peak or valley of crystal grain size for every kind of steel.

Key words: corrosion product scale, carbon dioxide corrosion, temperature, scale thickness, grain size, morphology, high-temperature high pressure autoclave, scanning electron microscope