篇名 | 熱浸鍍錚白銹生成之抑制研究 |
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卷期 | 11:1 |
並列篇名 | The Inhibition of the White Rust F ormation on Hot Dip Galvanized Products |
作者 | 鍾時俊 、 鮮祺振 、 施漢章 |
頁次 | 008-014 |
關鍵字 | 熱浸鍍梓 、 白銹 、 非鋁酸鹽轉化膜處理 、 hot dip galvanized steel 、 non-chromate chemical conversion treatment 、 white rust 、 EI |
出刊日期 | 199703 |
熱浸鍍鋅表面會生成具良好保護性的碳酸錚膜,保護辭材在一般環境中不致腐蝕太快o但是在台灣這種高濕度的環境下,熱浸鍍辭工廠的鍍件在戶外儲存時,卻遭遇到鍍件在表面上生成的白鏡問題。本研究探討生成白饒的環境因子,諸如相對濕度、氯離子、硫酸根離子等的臨界條件。熱浸鍍錚鑑件上為了防止自蝕,一般以錯酸鹽處理在表面形成保護膜來抑制自銳的生成。但是面對日趨嚴格的環保法規要求,發展對環境汗染度低的轉化膜處理方式就成為現今急需的工作。本研究開發使用非鋁酸鹽溶液的處理方式,以三價錯代替銘酸鹽中的六價鋁離子。藉著將處理過後的試片暴露在臨界環境表面鹽類濃度分佈1.5時/cm2NaCl、相對濕度80%'證實此種非錯酸鹽轉化膜處理對白饒有成功的抑制效果。
The good corrosion resistance of hot dip galvanized steel products in nature environments is due to the formation of a protective basic zinc carbonate film on the surface of the zinc coatings. However, in Taiwan, we face a severe white rust problem for freshly galvanized works stored in high humidity out-doors environments This paper investigated the critical factors such as relative humidity, chlorides, sulfates for the formation of white rust. Itwas recognized that a simple chromate treatment of galvanized products results in the production of a passive film on the surface of zinc coating which inhibits white rust formation. However, in response to/upcoming environmental regulations, we' should give a considerable amount of resources and time in the development of environmental friendly manufacturing processes, particularly in the areas of chromate compound reduction and environmentally compatible conversion treatments. This work concentrates on non-chromate chemical conversion treatments of galvanized coatings to provide good resistance to the formation of white rust. The present study develops the optimum condition for determining the protective value of non-chromate conversion coating by exposing the zinc specimen contaminated with 1.5μg/cm2 NaCl particles to 80% RH at room temperature.