00Cr13Ni5Mo2中D类夹杂物在酸化环境中的腐蚀行为研究

摘要

Chemical composition of D-type inclusion in super martensitic stainless steel ( SMSS) 00Cr13Ni5Mo2 was studied and the corrosion behavior of the inclusion with different sizes in solution consisted of HCl , HF and HAc was tracked .The results showed that the D-type inclusion is a kind of compound calcium aluminate .The width of large inclusion particle is 80μm, and the small one is 21 μm.There is a microcrack at the edge of inclusion with large size .The location of inclusion becomes the original position for pitting .The size of pit caused by the large size inclusion became lager along the direction of depth and transversal .It would have the negative effect on the corrosion resistance for SMSS .For the inclusion with small size , the ratio of depth to width of pit formed in corrosion solution is smaller .According to the results , the acceptance limit severity for type D inclusion was grade 2.%对商用的00 Cr13 Ni5 Mo2超级13 Cr材料中的D类夹杂物进行能谱分析，并对不同尺寸的D类夹杂物在HCl＋HF＋HAc强腐蚀性介质中的腐蚀行为进行了过程跟踪。研究结果表明，在00 Cr13 Ni5 Mo2中出现的D类夹杂物属于复合型的钙铝氧化物类夹杂，大颗粒的夹杂物尺寸宽度达到80μm，小颗粒的为21μm，且大颗粒夹杂物的边缘有裂纹。 D类夹杂物出现的位置成为酸化腐蚀过程中形成点蚀的原位，且在腐蚀的过程中大型夹杂物点蚀坑向纵深和横向两个方向发展，对材料的抗腐蚀性能产生非常不利的影响。而尺寸较小的夹杂物在腐蚀过程中形成的点蚀坑的深度也较浅，深宽比较小，危害性较小。从而确定了D类夹杂物可接受的等级为2级。