分享网上一篇讲涂层失效的文章|船舶涂装&海洋防腐蚀

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[复制链接] 只看楼主倒序阅读楼主发表于: 2012-12-30

复制前面一段给大家看看，需要的话后面有下载，供新造船的兄弟们参考和借鉴，修船的可以跳过了，都是常见的照片。

Introduction to Paint Problems.
There are many different types of coating failure, most of these result in paint or coating detachment. This sort paint failures guide describes the most common paint breakdown types and failures. Often the failure takes place for a combination of reasons that require an expert eye. Amtec offer a free initial e-mail or telephone consultation via the contact details above. You may even send photographs for examination.
Blistering
Blisters often take the form of clusters (or Rashes) of liquid filled, hemispherical bubbles at the paint/metal interface, although blisters can form between layers of paint, these are less common.
Typical blister rashes are shown in photographs 1 and 2. In order to give a sense of scale, a small notebook has been included in the latter figure.

Photograph 1. Blister rash at an area of localised contamination.

Photograph 2.  Blister rash.

Blisters either originate from ionic contamination on the substrate prior to coating or are due to soluble material leaching out from the coating itself and migrating to the interface with the substrate.  Water will always migrate through the film driven by osmosis and when the osmotic pressure within the blister balances the coating adhesion around its circumference, the blister ceases to grow.
Some Blisters can also be associated with areas of corrosion or sacrificial anodes.  In this instance, their growth is driven electrochemically driven and complex rules govern their eventual size.
Commonly, blisters do not show corroded material underneath (due to the highly alkaline blister fluid) and are of concern only in areas where they can be broken mechanically e.g. by the action of water or foot traffic.
When blisters occur late on in the lifetime of the coating they may indicate immanent serious failure - coating barrier properties measurements can sort this out - for more details on this contact Amtec.

Coating Failures & Coating Breakdown