"Measurements of a Trace Amount of Indoor Corrosion Using Kelvin Probe and QCM Methods"

“使用开尔文探针和 QCM 方法测量微量室内腐蚀”

基本信息

批准号：
03453066
负责人：
TSURU Tooru
金额：
$ 4.03万
依托单位：
Tokyo Institute of Technology
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1991
资助国家：
日本
起止时间：
1991 至 1992
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-03453066/
关键词：
ATMOSPHERIC CORROSION ELECTROLYTE THIN LAYER KELVIN METHOD DIFFUSION LIMITING CURRENT WATWER LAYER ELECTRONIC MATERIALS QUARTZ CRYSTAL MICROBALANCE QCM 火気腐食水晶振動子秤量法

项目摘要

New methods for measuring a trace amount of corrosion, which are based on Kelvin prove and quartz crystal microbalance (QCM) methods, have been developed to clarify the mechanisms of indoor corrosion in electronic equipments.This study is divided into three chapters.(1) "Development of a Vibrating reference electrode system" A new technique for measuring the potential distribution on a metal without touching the surface has been developed. We found that the use of parasitic capacitance is effective to reduce to time for measurement. By using this equipment, the surface potential of aluminum embedded in a copper sheet was measured.(2) "oxygen reduction under thin water layer" The reduction mechanisms of oxygen on metals with thin water layer have been investigated by Kelvin probe method. Particular attention has been given to the dependence of the oxygen reduction rate on the thickness of water layer. It was found that the reduction rate increases with decreasing the thickness of water layer down to the thickness of several tens mum. When the thickness is decreased further, it is independent of the thickness. It can be explained by a decrease of oxygen solvability and a pH change of water film.(3) "Impedance characteristics of metal corrosion under thin water layer"The impedance characteristics of steels and copper have been monitored in wet/dry cycle condition. This is capable of monitoring the corrosion rate simultaneously with the thickness of water layer. We found that the corrosion rate increases sharply, immediately after the dried surface is reimmersed into a solution and shortly before the surface dried out, and that it exhibits a maximum around the water layer thickness of 20 mum.

基于开尔文证明和石英晶体微天平（QCM）方法的微量腐蚀测量新方法已被开发出来，以阐明电子设备室内腐蚀的机理。本研究分为三章。（1） “振动参比电极系统的开发” 开发了一种无需接触表面即可测量金属电位分布的新技术。我们发现，使用寄生电容可以有效减少测量时间。利用该设备测量了嵌入铜片中的铝的表面电位。(2)“薄水层下的氧还原” 采用开尔文探针法研究了氧在薄水层金属上的还原机理。特别关注氧还原速率对水层厚度的依赖性。结果发现，随着水层厚度减小到几十微米，减少率增加。当厚度进一步减小时，它与厚度无关。这可以通过氧溶解度的降低和水膜pH值的变化来解释。(3)“薄水层下金属腐蚀的阻抗特性”在湿/干循环条件下监测了钢和铜的阻抗特性。这能够同时监测腐蚀速率和水层厚度。我们发现，在将干燥的表面重新浸入溶液中之后以及在表面干燥之前不久，腐蚀速率急剧增加，并且在水层厚度为 20 μm 左右时腐蚀速率达到最大值。