Development of thermal spray coatings with corrosion protecting and antifouling properties

为了开发具有防腐蚀和防腐蚀性能的热喷涂涂层，将铝-铜涂层、铝-锌涂层和锌涂层喷涂到钢基体上并浸入海中。在喷涂上述涂层（顶涂层）之前，用铝底涂层处理一些基材。当藤壶附着于铜含量低于20质量%的铝-铜合金涂层和铜含量低于40质量%的铝-铜混合物涂层时，在铜含量较高的涂层的情况下发生钢基材的生锈。锌涂层和含大于50质量%锌的铝-锌涂层具有防腐蚀和抗腐蚀特性。结果发现，铝底涂层的应用促进了顶涂层本身的腐蚀。在这种情况下，腐蚀开始于顶涂层/底涂层边界或底涂层/基材边界上或附近。腐蚀产物会使面漆浮起，并在面漆上积累。

For the purpose of development of thermal spray coatings with both corrosion protection and antifouling properties, aluminum-copper coatings, aluminum-zinc coating and zinc coatings are sprayed onto a steel substrate and are immersed in the sea. Some of the substrates are treated with an aluminum under-coat prior to the spraying of the above-mentioned coatings(top-coats). While barnacles adhered to the aluminum-copper alloy coatings of copper content lower than 20 mass% and to the aluminum-copper blend coatings of the copper content lower than 40 mass%, rusting of the steel substrates occurred in the case of the coatings of higher copper content. The zinc coatings and aluminum-zinc coatings containing more than 50 mass% zinc possess both corrosion protection and antifouling characteristics. It was found that the application of the aluminum under-coat promotes the corrosion of the top-coats themselves. In this case, the corrosion started on or near the top-coat/under-coat boundary or the under-coat/substrate boundary. The corrosion product(s) lift the top-coats and are also accumulated on the top-coats.