Corrosion and protection characteristics of zinc and manganese phosphate coatings

被引：144

作者：

Weng, D

Jokiel, P

Uebleis, A

Boehni, H

机构：

[1] HILTI LTD,MANCHESTER M17 1BY,LANCS,ENGLAND

[2] ETH HONGGERBERG,INST MAT CHEM & CORROS,CH-8093 ZURICH,SWITZERLAND

来源：

SURFACE & COATINGS TECHNOLOGY | 1997年 / 88卷 / 1-3期

关键词：

phosphating; corrosion protection; electrochemical measurement;

D O I：

10.1016/S0257-8972(96)02860-5

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

The corrosion and protection characteristics of zinc and manganese phosphate coatings in aqueous solutions are investigated by means of physical methods and electrochemical measurements. The results show that the insulation property of zinc phosphate coating is better than that of manganese phosphate, but the porosity of the former is inferior to that of the latter. The anodic current of coated samples decreases and polarization resistance increases compared to the substrate. The corrosion of phosphated steel exhibits the characteristics of no diffusion in acidic solution, a finite-length diffusion in neutral medium, and a semi-infinite diffusion in alkaline solution. Chemical dissolution is the primary form in the failure of phosphate coatings, which is induced by the electrochemical corrosion of the substrate. The protection ability of phosphate coatings mainly depends on their barrier performance.

引用

页码：147 / 156

页数：10

共 16 条

[1]

Freeman D.B., 1986, Phosphating and Metal Pretreatment

[2] CYCLIC VOLTAMMETRIC AND SCANNING ELECTRON-MICROSCOPIC EVALUATION OF THE CORROSION-RESISTANCE OF ZN-PHOSPHATED STEEL [J].