Effect of Surface Morphology on Electrochemical Behaviour of 1050 Alloy in Nitric Acid Solution

摘要

The effective use of 1050 alloy in the production of lithographic plates, where pitted and convoluted alloy surfaces are generated by alternating current electrograining, requires understanding of the manner of surface transformation under anodic and cathodic polarisation in HNO_3 solution. The present work uses chronoamperometry, combined with observation of the alloy surfaces, to investigate the local anodic and cathodic activity of the various iron-rich second phase particles present in the alloy. The electrochemical response of the alloy relates to changes in surface morphology, with the final stage being pitting. By suitable polarisation of the 1050 alloy, separation and control of the electrochemical activity of second phase particles and the aluminium matrix are possible, revealing their contributions to the cathodic and anodic behaviour of the alloy in HNO_3 solution.