鍍鋅鋼材、5%鍍鋁鋅鋼材及304不銹鋼之海洋大氣腐蝕研究

The Atmospheric Corrosion of Galvanized Steel, 5% Aluminum-Zinc Coated Steel and 304 Stainless Steel in Marine Environments

10.6376/JCCE.200109.0107

洪耀宗(Yaw-Tzong Horng)；王志華(Jyh-Hwa Wang)；施漢章(Han C. Shih)；徐希白(H. P. Shu)；林益全(Y. C. Lin)；劉日煬(J. Y. Liu)

熱浸鍍鋅 ； 5%熱浸鍍鋁鋅鋼材 ； 間隙腐蝕 ； 掃瞄式電子顯微鏡 ； 能量分散能譜儀 ； 化學分析電子儀 ； hot-dip galvanized steel ； 5% aluminum-zinc coated steel ； crevice corrosion ； SEM ； EDS ； ESCA

防蝕工程

15卷3期（2001 / 09 / 01）

107 - 114

繁體中文

鋼鐵材料常使用熱浸鍍鋅法進行防蝕處理，但在沿海鹽害地區及硫磺地區等高腐蝕性大氣環境使用時，耐蝕性則較差。本研究報告包括使用：高鍍鋅量熱浸鍍鋅鋼材、5％熱浸鍍鋁鋅鋼材及304不銹鋼材，自1993年在台灣西部沿海地區進行大氣腐蝕試驗。304不銹鋼材並模擬比較其存在間隙時之腐蝕差異性。 由實驗結果顯示高鍍鋅量之熱浸鍍鋅鋼材由於形成較厚的氧化物，使其對鋼底材有較佳之耐蝕保護性，304不銹鋼材料其腐蝕速率雖低，但是形成不均勻之腐蝕現象。利用掃瞄式電子顯微鏡(SEM)及能量分散能譜儀(EDS)觀察表面變化及表面元素分佈情形。並以化學分析電子儀(ESCA)分析腐蝕生成物。A級熱浸鍍鋅鋼材表面腐蝕生成物主要為Fe2O3，顯示已不再對鋼底材提供伽凡尼保護作用。

Hot-dip galvanizing (zinc coatings) has been widely used to improve the atmospheric corrosion resistance of steel for many years. It has good corrosion resistance in general atmospheric environment, but in coastal and sulfurous areas the zinc-coated steel corroded in short period. In this study the results of atmospheric corrosion test of high-zinc coated steel, 5% aluminum-zinc coated steel and 304 stainless steel at Taiwan western coastal area after seven years. The crevice corrosion behavior of 304 stainless steel was also analyzed in this study. The results obtained from the electrochemical measurement showed that the high-zinc coated steel provided the better anti-corrosion performance to the base metal because of the thicker zinc coated layer.304 stainless steel revealed non-homogeneous corrosion behavior even though it had the lower corrosion rate in marine environments. The corrosion behaviors and products were also analyzed with SEM, EDS and ESCA. The major corrosion product of class A zinc-coated steel in severe marine environment is Fe2O3, and this result shows that its zinc coating has no more galvanized protection to the base steel.