X70和16Mn钢腐蚀行为比较：Ⅲ.腐蚀磨损

用旋转试片装置和失重法比较X70钢和16Mn钢在含沙溶液中腐蚀磨损行为，研究流速、介质pH值、温度等因素影响.结果表明，2种管道钢存在相同临界流速，045 m/s，高于临界流速时，腐蚀磨损失重明显增加.同时温度升高也使钢的失重增加.此外腐蚀和磨损的交互作用十分明显，尤其在酸性介质中，交互作用影响可占总失重量的80%以上.X70钢抗腐蚀磨损性能较好.原因是X70钢易形成致密保护膜和有较高表面硬度.前者导致在酸性和弱碱性介质中，X70钢的失重较小，只有在强碱性下，二者腐蚀磨损失重几乎相同；后一因素使得X70钢在高流速下有较好抗磨损性. 

COMPARISON OF CORROSION BEHAVIOR OF X70 AND 16Mn STEELS Ⅲ. CORROSION - EROSION

The corrosion - erosion behavior of two pipeline steels, X70 steel and 16Mn steel in flowing sandy water solution is studied by means of electrochemical apparatus with rotating coupons and weight loss method. The influences of flow velocity, pH, and temperature on their corrosion-erosion behavior were investigated. The results showed that there was the same value for critical velocities, about 0.45m/s, for the two pipeline steels, above which, the weight loss increases dramatically. The weight loss also increased when temperature was rising. In addition, the synergism between corrosion and erosion was obviously observed. Especially in acid mediums, the percentage of the synergism in total weight loss was high up to more than 80 %. X70 steel had better resistance to corrosion-erosion, There are two reasons for these phenomena that X70 steel produce easily compact protective film, and the surface hardness of X70 is higher than that of 16Mn. The former factor results in the lighter weight loss of X70 steel in acidic and weakly alkaline condition, and the weight loss of 16Mn steel and X70 steel are almost equal only in the strongly alkaline condition. The latter factor makes a better erosion resistance of X70 steel.