A new corrosion test for organically coated galvanised steel products

A new approach to obtain predictions on cut-edge corrosion resistance in or ganic coated galvanised steel (OCS) products has been developed which. unli ke many accelerated tests, can be performed in any desired external environ ment. The testing procedure is based on the monitoring of cationic zinc (Zn 2+) released from OCS panels prepared prior to exposure with an exceptional ly high cut edge length per unit area. There is an excellent correlation be tween the total quantity of cationic zinc leached from the exposed edge ove r a three-month period of external exposure and the observed cut edge corro sion performance after a 4-year natural external exposure period in the sam e environment. The results of conventional accelerated testing methodologie s have been found to fail to accurately predict external exposure as accura tely as this testing procedure. The test can be performed in any weathering regime and can accurately predict the difference in environmentally sensit ive materials performance.