湿法磷酸设备用材的耐腐蚀性

Corrosion Resistance of Materials for Hot Wet-process Phosphoric Acid Equipment

湿法磷酸生产中的工作介质,对设备及其材料具有强烈的腐蚀作用,对适合于此条件下工作的铸造高铬镍不锈钢J_1合金进行了均匀腐蚀、晶间腐蚀和点腐蚀等试验。同时,对材料试样表面钝化膜的结构及组成进行测试和分析。试验研究结果表明,J_1合金在磷酸介质中具有优良的耐均匀腐蚀、晶间腐蚀和点腐蚀性。这是由于材料中各合金元素及其含量间的合理匹配,使材料在腐蚀介质中能够发生钝化和具有维持钝化的能力。

Materials and equipment corrode and erode drastically with theactuating medium in the production of hot wet-process phosphoric acid. Inthis process, a cast high Cr-Ni stainless steel J-1 type alloy is most suita-ble for building the equipment. Iso-corrosion, intergranular corrosion and pitting corrosion test, etc.,have been carried out to study corrosion resisance of the alloy. AES and XPS are used to determine construction and composition of thepassive film. Test results show that the J-1 type alloy possesses excellent corrosionresistance. It enables the possipility of passivity and can maintainpassivity,which results from the reasonable marriage of various elements.