A critical review of corrosion rate calculations of Mg-Al-Li alloys using traditional mass loss measurements

Anna Dobkowska , Bogusława Adamczyk-Cieślak , Jarosław Mizera

Abstract

The corrosion rate (CR) calculations were performed for AZ31, AZ31-4Li, AZ31-7.5Li and AZ31-15Li Mg alloys after extrusion, and after extrusion with subsequent heat treatment. CR was obtained using three different mass loss (ML) measurements: i) traditional ML measurements where weighing before and after immersion was being implied, ii) by atomic absorption spectroscopy, where number of Mg²⁺ ions were calculated from the solution after immersion, and iii) by ML measurements in an artificial atmosphere. As results show, there are many differences in CR results obtained by these techniques. When CR is being calculated for multi-alloy-ing materials, all possible anodic reactions which can take place during dissolution of immersed samples in the solution, should be considered.