Effect of the cooling rate on the electrochemical behaviour of 2017 aluminium alloy

Effect of the cooling rate on the electrochemical behaviour of 2017 aluminium alloy

Szklarz, Z. Krawiec, H. Rogal, Ł. 

AGH University of Science and Technology, Faculty of Foundry Engineering, 23 Reymonta St., Krakow, 30-059, Poland

Institute of Metallurgy and Materials Science of the Polish Academy of Sciences, 25 Reymonta St., Krakow, 30-059, Poland

1 October 2015
7 January 2016
11 May 2016
| Citation



The influence of cooling rate on the microstructure and on the electrochemical behaviour of 2017 aluminium alloy is studied in this work. The electrochemical measurements were conducted at the mesoscale by using Electrochemical Microcell Technique (EMT) with 300 μm capillary in 0.1 M NaCl aqueous solution. The microstructure of specimens from the internal part of ingot and quick cooled sample were determined by optical microscope and SEM/EDX analysis. The corrosion behavior and the passive properties were studied by means of Open Circuit Potential (OCP) and Electrochemical Impedance Spectroscopy (EIS). It is observed that slow solidification causes irregular grain growth with very large and very small grains. Moreover heterogeneities in the matrix were observed in the form of needle shaped particles. High rate of cooling causes the presence of quite small regular grains and homogenous matrix. The specimens of quick cooled 2017 alloy exhibit higher corrosion potential and the dissolution of metal starts at higher anodic potential compared to the non-treated specimens.

1. Introduction
2. Experimental Procedure
3. Results and Discussion
4. Conclusions

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