Eventos Anais de eventos
COBEM 2021
26th International Congress of Mechanical Engineering
Corrosion resistance of cold-drawn ZK60A Mg-alloy as a function of strain-hardening
Submission Author:
Pedro Paiva Brito , MG , Brazil
Co-Authors:
Pedro Paiva Brito, Thais Roberta Campos, Beatriz Ferreira, Klaus Silva, Diogo Azevedo de Oliveira, Jonathan Crosara, Rodrigo Coelho
Presenter: Pedro Paiva Brito
doi://10.26678/ABCM.COBEM2021.COB2021-2137
Abstract
Magnesium alloys exhibit elevated strength to weight ratio, high capacity for absorbing mechanical vibrations as well as good machinability and castability. One of the main disadvantages of magnesium alloys is their elevated chemical reactivity, which might limit application in certain media or impose protective measures. As such, efficient and safe use of magnesium alloys requires an understanding of their corrosion resistance in relation to previous processing/microstructure conditions which might influence electrochemical behavior. In the present work, an exploratory work of the corrosion resistance of magnesium alloy ZK60A (0.5%Zr and 5.5%Zn) in 3.5%NaCl solution containing naturally dissolved oxygen was performed. Tests were performed on samples in the T5 (aged) condition and submitted to different levels of cold-work by drawing in order to evaluate the relation between strain-hardening and corrosion behavior. To this end, mechanical properties of the samples (tensile test and hardness) and microstructure (crystallographic texture). The corrosion resistance was evaluated by means of electrochemical impedance spectroscopy and potentiodynamic polarization. The results obtained revealed that the drawing process causes the (10-10) planes to become perpendicular to the drawing direction, as opposed to the initially randomly textured samples in the T5 condition. The corrosion resistance could was found to be dependent on the level of strain-hardening, with a small increase in corrosion rate as a function of cold-work.
Keywords
corrosion, Strain Hardening, Crystallographic texture, Cold-drawing
