阀用K417合金在南海环境下的海洋大气腐蚀行为研究

Corrosion Behavior Research of K417 Alloy under the Marine Atmosphere Environment in the South China Sea

在南海某岛礁上对阀用K417镍基合金进行了为期24个月的自然暴晒试验。暴晒一定周期试样取回,利用宏观形貌、微观形貌、腐蚀速率和电化学分析等手段研究了其在典型南海海洋大气环境中的腐蚀行为特征。结果表明:K417合金在南海大气环境下腐蚀速率十分缓慢,具有良好的抗海洋大气腐蚀能力。合金暴晒12个月以上仍未出现明显腐蚀产物。合金的点蚀坑尺寸也很小,暴晒24个月后平均点蚀坑深度仅为0.34μm。电化学测试结果也说明K417合金在海洋大气环境下具有优越的耐腐蚀能力。

A 24-month natural exposure test of K417 nickel-based alloy was conducted on one island in the South China Sea.Afterwards,the corrosion behavior of the alloy was studied by means of macroscopic morphology observation,microscopic morphology observation,corrosion rate measurement and electrochemical test.The results show that:the corrosion rate of K417 alloy is very slow,with a good ability against marine atmosphere corrosion.There are no obvious corrosion products after exposure for 12 months.The pit sizes of alloys are also small,whose average depth is only 0.34μm after exposure for 24 months.The electrochemical test result also indicates that K417 alloy has an excellent ability against the marine atmosphere corrosion.