Investigating the long term effects of creep with chromate free primers

爬行在各行各业中都有负面的含义。这在卷材涂层金属领域没有什么不同。蠕变描述了当腐蚀性材料不知不觉地在油漆金属界面的两半之间强行移动时发生的情况。这个过程从一块油漆金属的切割边缘开始，向内推进的速度由附着力、防腐武器对着它排列起来，当然还有推动化学物质前进的条件的强度决定。Galvalume的无铬底漆受到边缘腐蚀的严重影响。有些人认为这会在一段时间后减缓，而Galfan和HDG等基材上的涂层在一段时间后(5年)就会赶上切割边缘的蠕变程度，但在Beckers我们没有看到这一点。我们想要了解盖洛姆和其他两种衬底的边缘腐蚀之间的区别。为此，我们希望将电化学方法；扫描振动电极技术(SVET)应用于少量选择的底漆，并在上述衬底上涂抹面漆。项目目标：该项目的目标是利用电化学技术表征Galvalume、Galfan和热镀锌钢板上发生的刃口腐蚀。面板将涂上含铬底漆和不含铬底漆以及面漆。将尝试最多2种不同的防腐颜料。将调查任何差异，并解决影响切割边缘腐蚀速度的参数，以努力减缓边缘腐蚀速度。将尝试电化学测试、盐雾和外部暴露之间的相关性。

Creep has negative conations in many walks of life. It is no different in the field of Coil Coated metal. Creep describes what happens when corrosive materials insidiously force their way between the two halves of the paint metal interface. The process starts from the cut edge of a piece of painted metal advancing inwards at a rate determined by the strength of adhesion, the anticorrosive weaponry lined up against it and of course the strength of the conditions pushing the chemicals forward.Chromate Free Primers for Galvalume suffer badly from edge corrosion. Some people believe that this slows down after a period of time and coatings on substrates such as Galfan and HDG 'catch up' on the extent of creep from the cut edge after a period of time (5 years) but at Beckers we have not seen this. We would like to understand the differences between edge corrosion on galvalume and the other 2 substrates. To this end we would like to apply the electrochemical methodology; Scanning Vibrating Electrode Technique (SVET) to a small selection of primers plus topcoats applied to the above mentioned substrates. Project aims:The aim of the project is to characterise the cut edge corrosion that takes place on Galvalume, Galfan and Hot Dip Galvanised Steel using electro-chemical techniques. The panels will be coated with chromate containing and chromate free primers plus topcoats. A maximum of 2 different anti-corrosive pigments will be tried. Any differences will be investigated and the parameters that impact on the speed of cut edge corrosion will be addressed in an effort to slow down the rate of edge corrosion. Correlations between electrochemical testing, Salt Spray and Exterior exposures will be attempted.