Experimental Analysis of Corrosion Resistance on Columnar to Equiaxed Transition Region of as Cast Structures of AL:-CU Alloys

In the present article, in order to investigate the corrosion resistance tendency on both sides of the columnar to equiaxed transition CET , some samples of Al-Cu alloys 5 and 8 wt- Cu were prepared on the columnar and on the equiaxed sides of the casting and subjected to corrosion tests. The corrosion resistance has been analysed by both the electrochemical impedance spectroscopy technique and Tafel extrapolation method conducted in a 3 NaCl solution at room temperature. It was found that both columnar and equiaxed morphologies at the CET region, for each alloy examined, have attained similar experimental electrochemical impedance and polarisation results. The secondary dendrite arm spacings l2 on both columnar and equiaxed sides of the CET region are very similar in any case experimentally examined and the resemblance on the corrosion resistance of columnar and equiaxed structures has been attributed to the similarity of such micro structural parameter. Ganesan Venkatachalam "Experimental Analysis of Corrosion Resistance on Columnar to Equiaxed Transition Region of as Cast Structures of AL-CU Alloys" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-6 , October 2018, URL: http://www.ijtsrd.com/papers/ijtsrd18733.pdf