Localized impedance measurements of AA2024 and AA2024‐T3 performed by means of AFM in contact mode

Abstract

Purpose

The purpose of this paper is to present the results of an atomic force microscopy (AFM) based approach to local impedance spectroscopy (LIS) measurement performed on AA2024 and AA2024‐T3 aluminium alloys.

Design/methodology/approach

AFM‐LIS measurements were performed ex‐situ without the electrolyte environment, so in fact the electrical not electrochemical impedance was obtained.

Findings

Relative local impedance values recorded for AA2024 alloy during the researches carried out were maximally approximately three orders of magnitude higher than the ones obtained for age‐hardened AA2024‐T3 alloy. Moreover, in the case of AA2024‐T3 alloy, a region located in the interior of α crystals exhibited localized impedance one order of magnitude higher than that measured at its grain boundary when affected by intergranular corrosion.

Originality/value

The paper presents differences in localized impedance between grain and grain boundaries activity.

Citation

Arutunow, A., Zieliński, A. and Tobiszewski, M.T. (2013), "Localized impedance measurements of AA2024 and AA2024‐T3 performed by means of AFM in contact mode", Anti-Corrosion Methods and Materials, Vol. 60 No. 2, pp. 67-72. https://doi.org/10.1108/00035591311308038