海水流速对典型金属管材腐蚀行为的影响

Effect of Flow Velocity on Corrosion Behavior of Typical Metal Materials for Pipes in Seawater

利用管路模拟腐蚀试验装置和电化学分析手段对比研究了4种典型海洋用金属管路材料在静态和动态海水环境中的腐蚀行为。结果表明，在静态海水环境中，碳钢的腐蚀速率远高于304不锈钢、B10铜合金和纯钛TA2。4种材料在3～10m／s流速内均为湍流腐蚀。流速为10m／s时，B10铜合金的动态腐蚀敏感性比304钢强，主要原因是在动态海水中B10的活化溶解区明显宽于304不锈钢，其成膜速度较慢。在静态和动态海水冲刷环境条件下，TA2由于在表面形成致密稳定的钝化膜，基本不发生腐蚀，是耐海水腐蚀性能最优异的管路材料。

The corrosion behavior of four typical metal materials for pipes was studied in static and dynamic seawater by pipe flow apparatus and electrochemical measurements. The results showed that the corrosion rate of carbon steel in nature seawater was higher than that of 304 stainless steel, B10 alloy and TA2. All of the fluid types of four materials were turbulence in the flow velocities between 3 m/s to 10 m/s. The corrosion behavior of B10 alloy was more sensitive than that of 304 stainless steel in the flow velocity of 10m/s, the main reason was the activation dissolve zone of B10 was wider than 304, which caused protective layer on the surface of B10 formed more slowly than that of 304. TA2 did not corrode in both static and dynamic conditions due to the most dense and stable corrosion product formed on the surface, which was the most excellent material for pipe in seawater.