工业纯钛的缝隙腐蚀探讨

Crevice corrosion discussion of commercial pure titanium

采用10％FeCl3·6H2O溶液和1mol／L硫酸溶液进行不同温度下的浸泡试验，以3．56％NaCl溶液和1mol／L硫酸为介质，进行不同条件下的电化学测试，对钛的缝隙腐蚀行为进行研究。实验结果表明温度对缝隙腐蚀有较大的影响：在10％FeCl3·6H2O介质中，当温度低于50℃时未发生缝隙腐蚀，当温度高于80℃，缝隙腐蚀随温度升高而增大；在1mol／L硫酸介质中，缝隙腐蚀随温度的升高而加剧；在10％FeCl3·H2O介质中，临界缝隙尺寸随温度的升高而增大。在氧化性的三氯化铁介质中的缝隙腐蚀速率明显小于还原性稀硫酸介质中的缝隙腐蚀速率。

The immersion tests at various temperatures were made with10% FeCl3·6H2O solution and 1 mol/L sulfuric acid solution, theelectrochemical tests in various conditions with 3. 56% NaCl solu-tion and 1 mol/L sulfuric acid solution as mediums were made toresearch the crevice corrosion behavior of titanium. The resaltshows that the temperatures have an important effect on the crevice corrosion. In 10% FeCl3·6H2O solution, no crevice corro-sion occurred when the temperature was below 50℃， the crevicecorrosion would extend with the rise of temperature when the tem-perature was over 80℃; in 1 mel/L sulfuric acid solution, thecrevice corrosion extended with the rise of temperature. In 10%FeCl3·6H2O solution, the critical crevice sizes extended with therise of temperature. The crevice corrosion rate of titanium in the oxidative ferric chloride solution was much less than that in thereductive dilute sulfuric acid solution.