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. 2023 Oct 11;16(20):6651.
doi: 10.3390/ma16206651.

Improvement in Corrosion Performance of ECAPed AZ80/91 Mg Alloys Using SS316 HVOF Coating

Gajanan M Naik  1 , Priyaranjan Sharma  2 , Gajanan Anne  3 , Raj Kumar Pittala  2 , Rahul Kumar  4 , Gnane Swarnadh Satapathi  5 , Ch Sateesh Kumar  6   7 , Filipe Fernandes  8   9
Affiliations

Improvement in Corrosion Performance of ECAPed AZ80/91 Mg Alloys Using SS316 HVOF Coating

Gajanan M Naik et al. Materials (Basel). .

Abstract

Mg AZ80/91 alloys are highly popular due to their lightweight, high strength-to-weight ratio, and good machinability. However, their moderate mechanical properties and corrosion resistance have limited their use in the automotive, aerospace, and defense sectors. This study primarily aims to enhance the mechanical performance and corrosion resistance of Mg AZ80/91 alloys, making them more suitable for applications in the aerospace and automotive industries. Firstly, equal-channel angular pressing (ECAP) of Mg AZ80/91 alloys has been attempted to improve their mechanical properties. Secondly, a high-velocity oxy-fuel (HVOF) coating of SS316 was applied over the Mg AZ80/91 substrate to enhance its corrosion resistance. In the second step, an HVOF coating of SS316 is applied over the Mg AZ80/91 substrate for better corrosion resistance. The experimental findings demonstrate that the application of an SS316 coating on the ECAP-4P AZ80/91 Mg alloy substrate results in a uniform and dense layer with an average thickness of approximately 80 ± 5 µm. The HVOF-based SS316 coating on 4P-ECAP leads to a noteworthy enhancement in microhardness and a reduction in the corrosion rate, especially in a NaCl solution (3.5 wt.%). This improvement holds great promise for producing reliable, long-lasting, and resilient automotive, aerospace, and defense components. The application of an HVOF-based SS316 coating onto the AZ80 Mg alloy, which had not undergone ECAP treatment, led to a substantial enhancement in corrosion resistance. This resulted in a notable decrease in the corrosion current density, reducing it from 0.297 mA/cm2 to 0.10 µA/cm2.

Keywords: ECAP; HVOF; SS316 coating; corrosion; microhardness.

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Conflict of interest statement

The authors declare no conflict of interest related to this research study or its findings.

Figures

Figure 1
Figure 1
Experimental data of SS316 powder. (a) SEM image indicating variation in particle size, (b) graphical representation of particle size distribution.
Figure 2
Figure 2
Experimental plan of current research work.
Figure 3
Figure 3
Microscopic and elemental analysis of HVOF-based SS316 coating formed on AZ80 Mg alloy. (a) SEM image of SS316 coating on non-ECAPed specimen; (b) EDS analysis of non-ECAPed specimen; (c) SEM image of SS316 on coating on ECAP-4P specimen; (d) interface region of SS316 coating and ECAP-4P specimen.
Figure 4
Figure 4
Microscopic and elemental analysis of HVOF-based SS316 coating formed on AZ91 Mg alloy. (a) SEM image of SS316 coating on non-ECAPed specimen; (b) EDS analysis of non-ECAPed specimen; (c) SEM image of SS316 on coating on ECAP-4P specimen; (d) interface region of SS316 coating and ECAP-4P specimen.
Figure 5
Figure 5
Sub-surface microhardness of SS316-coated AZ80 Mg alloys.
Figure 6
Figure 6
Sub-surface microhardness of SS316-coated AZ91 Mg alloys.
Figure 7
Figure 7
Graphical representation of corrosion behavior of HVOF-based SS316-coated ECAPed AZ80 Mg alloy.
Figure 8
Figure 8
Graphical representation of corrosion behavior of HVOF-based SS316-coated ECAPed AZ91 Mg alloy.
Figure 9
Figure 9
Corrosion potential data sheet corresponding to HVOF-based SS316-coated non-ECAPed/ECAPed AZ80/91 Mg alloy.
Figure 10
Figure 10
Corrosion morphology and EDS analysis of HVOF-based SS316-coated ECAP-4P AZ80 Mg alloys.
Figure 11
Figure 11
Corrosion morphology and EDS analysis of HVOF-based SS316-coated ECAP-4P AZ91 Mg alloys.
Figure 12
Figure 12
Graphical representation of corrosion rate of ECAP-4P AZ80/91 Mg alloy before and after the application of SS-316 coating.
See this image and copyright information in PMC

References

    1. García-Rodríguez S., López A.J., Torres B., Rams J. 316L stainless steel coatings on ZE41 magnesium alloy using HVOF thermal spray for corrosion protection. Surf. Coat. Technol. 2016;287:9–19. doi: 10.1016/j.surfcoat.2015.12.075. - DOI
    1. Gnedenkov S.V., Sinebryukhov S.L., Mashtalyar D.V., Imshinetskiy I.M. Composite fluoropolymer coatings on Mg alloys formed by plasma electrolytic oxidation in combination with electrophoretic deposition. Surf. Coat. Technol. 2015;283:347–352. doi: 10.1016/j.surfcoat.2015.10.066. - DOI
    1. Gray J., Luan B. Protective coatings on magnesium and its alloys—A critical review. J. Alloys Comp. 2002;336:88–113. doi: 10.1016/S0925-8388(01)01899-0. - DOI
    1. Jiang J., Zhou Q., Yu J., Ma A., Song D., Lu F., Chen J. Comparative analysis for corrosion resistance of micro-arc oxidation coatings on coarse-grained and ultra-fine grained AZ91D Mg alloy. Surf. Coat. Technol. 2013;216:259–266. doi: 10.1016/j.surfcoat.2012.11.055. - DOI
    1. Ma X.Q., Gandy D.W., Frederick G.J. Innovation of ultrafine structured alloy coatings having superior mechanical properties and high temperature corrosion resistance. J. Ther. Spray Technol. 2008;17:933–941. doi: 10.1007/s11666-008-9263-4. - DOI

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