用于海洋环境下活化腐蚀防护的高性能电弧喷涂层

采用铝或锌涂层的活性腐蚀防护是热喷涂技术应用最多的领域.每年大约要消耗20,000吨的喷涂线材,并且未来需求还在增加.热喷涂技术及材料无论是单独还是一起在海洋环境下使用,都有一定的标准.海上风力发电机（OWET）要求维护间隔时间尽可能长,这可以通过使用长寿命的表面涂层来满足使用要求.目前,金属喷涂涂层主要用于OWET的高应力部件,如法兰、框架和安装面.在实验室测试的过程中,研究了多种用于OWET的双涂层体系的抗腐蚀效果,其中金属涂层关注最多.制备了不同厚度和特性的Zn/A1和Al涂层,对部分涂层进行封孔处理,并制备有机涂层形成多层涂层体系.其目的之一是制备地氧含量的防护涂层,并和目前标准的工艺进行对比.依照ISO20340标准5]对涂层和标样涂层的抗腐蚀性能进行了25周的循环老化测试评价,评估标准为：涂层划痕处的腐蚀和渗透、涂层起泡和锈蚀程度,以及涂层与基材的结合力.测试结果表明,喷涂金属涂层是一种有效的改善材料的抗腐蚀性能方法.采用活性气体作雾化气体的电弧喷涂或冷喷涂制备Zn/A115涂层能够提升涂层的防护效果,并且可以降低涂层的厚度,具有较好的经济前景.

High Performance Arc Sprayed Coatings for Active Corrosion Protection in Offshore Applications

Active corrosion protection with aluminium or zinc is thelargest area of application for thermal spraying. Every year, about 20,000 tonnes of wire of these materials are processed; and the trend is upward. In the commercial offshore sector, spray application of both materials-separately or combined-is to some extent the standard. In the area of offshore wind energy towers （OWET）, there is an additional requirement to make the maintenance intervals as long as possible, which can be met in part by using long-lived surface coatings. Hitherto, spray metallisation has been used mainly on the mechanically highly stressed components of OWET, such as flanges, frames and fitting surfaces. In the course of laboratory tests, the corrosion- protective effects of various duplex systems that are suitable for use in OWET have now been investigated. Particular attention was paid to the form of the metallisation. Zn/A1 and A1 layers of varying thickness and characteristics were applied, in some cases sealed, and provided with a multi-layer organic coating system. One of the objectives was to manufacture low-oxide protective coatings, and to compare these with systems that are today regarded as standard. The protective characteristics of the systems were assessed and compared in the course of a 25-week cyclic aging test as defined in ISO20340tSj. The assessment criteria were： corrosion and penetration at the scratch, degree of blistering, degree of rusting, and adhesion to the substrate. The results of the tests demonstrate possible ways of improving the corrosion protection of spray metallisation. Improvement of the protective characteristics is possible, even in the case of Zn/A115 spray metallisation by using active gases as the atomising gas or using cold-gas metallisation. The thickness of the coating can be reduced, which can bring further economic benefits.