In this study, a dynamic corrosion device for cement paste was developed according to the underground conditions of oil and natural gas wells, which possess a largely dynamic and constantly migrating corrosive medium. Using CO₂ as the corrosion medium, the effects of the three corrosion conditions, namely static non-migration, dynamic non-migration, and dynamic migration of the corrosion solution, on the corrosion process of cement paste were studied. The results revealed that under static non-migration conditions, the corrosion products aggregated on the surface of the cement paste samples and filled the pores of the samples, thereby slowing the corrosion rate. Conversely, the ability of the corrosion products to fill the pores weakened and the leaching effect was enhanced in samples under dynamic non-migration conditions because of the flowing corrosion medium, which further accelerated the corrosion process. The migration of the corrosion medium strengthened the leaching effect of CO₂ in the samples. The cracks on the surface of the samples were wider and longer than those of the non-migrated samples. This was more conducive to the invasion of corrosive media and for the acceleration of the corrosion process. These results not only enhance the understanding of cement corrosion, but also provide a new perspective and reference for corrosion research of oil-well cement paste.

本研究根据油气井井下腐蚀介质大、动态不断迁移的情况，研制了一种水泥浆动态腐蚀装置。使用 CO ₂以腐蚀介质为研究对象，研究了腐蚀液静态不迁移、动态不迁移和动态迁移三种腐蚀条件对水泥浆体腐蚀过程的影响。结果表明，在静态非迁移条件下，腐蚀产物在水泥浆体试样表面聚集并填充试样的孔隙，从而减缓腐蚀速率。相反，在动态非迁移条件下，由于腐蚀介质的流动，腐蚀产物填充孔隙的能力减弱，浸出效果增强，进一步加速了腐蚀过程。腐蚀介质的迁移增强了CO ₂的浸出效果在样品中。样品表面的裂纹比非迁移样品的裂纹更宽更长。这更有利于腐蚀介质的侵入和加速腐蚀过程。这些结果不仅增进了对水泥腐蚀的认识，也为油井水泥浆体腐蚀研究提供了新的视角和参考。