Investigating the long term effects of creep with chromate free primers

蠕变在生活的许多方面都有负面影响。这是没有什么不同的领域线圈涂层金属。蠕变描述了当腐蚀性材料在油漆金属界面的两半之间不知不觉地强行进入时所发生的情况。该过程从一片涂漆金属的切割边缘开始，以取决于附着力的速度向内推进，防腐蚀武器排列在其上，当然还有推动化学品前进的条件强度。Galvalume的无铬底漆严重遭受边缘腐蚀。有些人认为，经过一段时间后，这种情况会减缓，一段时间（5年）后，Galfan和HDG等基材上的涂层会“赶上"切割边缘的蠕变程度，但在Beckers，我们还没有看到这种情况。我们想了解galvalume和其他2种基材的边缘腐蚀之间的差异。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和涂在上述基材上的面漆。项目目标：该项目的目的是使用电化学技术解决镀锌、Galfan和热浸镀锌钢的切割边缘腐蚀问题。面板将涂有含铬酸盐和不含铬酸盐的底漆和面漆。将尝试最多2种不同的防腐颜料。将研究任何差异，并解决影响切割边缘腐蚀速度的参数，以减缓边缘腐蚀速度。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.