Influence of the microstructure of Mg-Ca magnesium alloy with TiO₂/ZrO₂ nano-oxide ALD coating on the functional properties

Abstract

The paper presents an analysis of the results of evaluating the effect of microstructure obtained by methods of severe plastic deformation (SPD) - equal-channel angular pressing (ECAP) and high-pressure torsion (HPT) - on the mechanical and operational properties of the Mg-1%Ca alloy. The influence of the ZrO2 nano-oxide coating deposited using the atomic layer deposition (ALD) technology was considered in comparison with the uncoated material under study. At the same time, it was noted that the application of a ZrO2 nano-oxide coating by the ALD method made it possible to increase the mechanical characteristics of the ECAP samples by about 20% (the ultimate strength was 205 MPa after ECAP and 262 MPa for ECAP samples with ALD coating). The lowest values of the adhesive component of the friction coefficient were observed on samples after SPD treatment using the HPT method with an applied ZrO2 nano-oxide coating. However, it was found that both the initial material of the study and after SPD treatment by ECAP, the Mg-1% Ca alloy demonstrates a slightly lower damping ability during the deposition of ZrO2 films.