不锈钢钝化膜表面微观形貌特征的ECSTM研究  

In-situ ECSTM investigation on passivation surface for polycrystalline stainless steel

作　　者：胡艳玲[1] 胡融刚[1] 邵敏华[1] 卓向东[1] 林昌健[1] 

机构地区：[1]厦门大学材料科学与工程系

出　　处：《电子显微学报》2001年第5期631-635,共5页Journal of Chinese Electron Microscopy Society

基　　金：国家自然科学基金资助项目 (5 95 2 5 10 2 ;5 98710 43)~~

摘　　要：本文利用扫描隧道显微镜及自制的无源恒电位仪组成电化学扫描隧道显微镜 (ECSTM) ,对浸泡在 0 5mol LH2 SO4 +0 0 2mol LNaCl溶液中的Cr11Ni13 不锈钢表面进行控电位原位研究 ,获得不锈钢表面纳米尺度的动态形貌图像。实验表明 :当试样处于开路电位时 ,不锈钢表面为自然形成的均匀椭球形氧化物晶粒。当电位控制在阴极和阳极活性溶解区时 ,原来的氧化物晶粒随时间延长而缓慢消失。当电位控制在活化、钝化过渡区时 ,表面钝化膜晶粒尺寸变大 ,形状转变成半球形 ;同时有新的钝化膜晶粒生成。当控电位在钝化区时 ,钝化膜晶粒转变成月牙形 ;随电位升高 ,钝化膜发生动态重整 :晶粒呈定向有序化生长 。In this article, in situ topographical information of passivated surface for polycrystalline stainless steel(Cr 11 Ni 13 SS)was obtained by ECSTM. Topography of the same region was traced by STM while potentials in different regions were applied to the sample in 0 5mol/L H 2SO 4+0 02mol/L NaCl. When the applied potential changed from active dissolution region to 0V, formation of passive grains of 200nm×150nm×10nm in size was observed on the surface. While the potential rose to 0 2V, grooves between grains were leveled and grains tended to fuse together, forming a uniform shape. As the potential moving in anodical direction, the passive grains grew slowly and oriented along x y plane. Surface roughness parameter S a also became smaller with increasing potentials.

关 键 词：扫描隧道显微镜 钝化膜 不锈钢 原位研究 微观形貌 

分 类 号：O647.1[理学—物理化学]