Corrosion resistance of thermally sprayed Al and Al/SiC coatings on Mg

Campo, M.; Carboneras, M.; López, María Dolores; Torres, B.; Rodrigo, P.; Otero, E.; Rams, J.

doi:10.1016/j.surfcoat.2009.03.057

Cited by 109 publications

(35 citation statements)

References 9 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…It was found that the corrosion resistance of the Cr 3 C 2 -NiCr coating is reduced by either (a) the presence of porosity, especially when the pores are interconnected [12], as can be seen in Figure 1a, or (b) the presence of carbides [13], as illustrated in Figure 1b. Guilemany et al [6] showed that defects such as pores and cracks play a key role in the integrity of the coating-substrate system and can negatively affect the corrosion resistance, as they act as main paths for the electrolyte to pass the coating and reach the substrate.…”

Section: Introductionmentioning

confidence: 99%

Electrochemical Behavior of Bilayer Thermal-Spray Coatings in Low-Temperature Corrosion Protection

Sadeghimeresht

Markocsan

2017

Coatings

View full text Add to dashboard Cite

Cr 3 C 2 -NiCr coatings are greatly used to protect critical components in corrosive environments and to extend their lifetime and/or improve functional performance. However, the pores formed during spraying restrict the coating's applicability area for many corrosion protection applications. To overcome this technical challenge, bilayer coatings have been developed, in which an additional layer (the so-called "intermediate layer") is deposited on the substrate before spraying the Cr 3 C 2 -NiCr coating (the so-called "top layer"). The corrosion behavior of the bilayer coating depends on the composition and microstructure of each layer. In the present work, different single-layer coatings (i.e., Cr 3 C 2 -NiCr, Fe-and Ni-based coatings) were initially sprayed by a high-velocity air fuel (HVAF) process. Microstructure analysis, as well as electrochemical tests, for example, open-circuit potential (OCP) and polarization tests, were performed. The potential difference (∆E) had a great influence on galvanic corrosion between the top and intermediate layers, and thus, the coatings were ranked based on the OCP values (from high to low) as follows: NiCoCrAlY > NiCr > Cr 3 C 2 -NiCr > NiAl > Fe-based coatings (alloyed with Cr) > pure Ni. The Ni-based coatings were chosen to be further used as intermediate layers with the Cr 3 C 2 -NiCr top layer due to their capabilities to show high OCP. The corrosion resistance (R p ) of the bilayer coatings was ranked (from high to low) as follows: NiCoCrAlY/Cr 3 C 2 -NiCr > NiCr/Cr 3 C 2 -NiCr > NiAl/Cr 3 C 2 -NiCr > Ni/Cr 3 C 2 -NiCr. It was shown that splat boundaries and interconnected pores are detrimental for corrosion resistance, however, a sufficient reservoir of protective scale-forming elements (such as Cr or/and Al) in the intermediate layer can significantly improve the corrosion resistance.

show abstract

Section: Introductionmentioning

confidence: 99%

Electrochemical Behavior of Bilayer Thermal-Spray Coatings in Low-Temperature Corrosion Protection

Sadeghimeresht

Markocsan

2017

Coatings

View full text Add to dashboard Cite

show abstract

“…Thus, it has been expected that Al coating on Mg alloys should be an effective way to improve their corrosion resistance. Recently much effort has been devoted to the development of Al coating techniques including plating [7], anodizing [8,9], thermal spray [10][11][12][13] and laser cladding [14,15]. However, in these attempts, several problems still remain unsolved, such as thermal damages of the substrate materials and necessities of surface pretreatments or post-treatments.…”

Section: Introductionmentioning

confidence: 99%

Superplastic behavior of Al-coated Mg alloy sheet

Tokunaga¹,

Matsuura²,

Ohno³

2014

Journal of Alloys and Compounds

View full text Add to dashboard Cite

“…In previous researches, Al was co-deposited with SiC or Al 2 O 3 particles to improve the stability of the ceramic coat on Mg alloy substrate (Ref [14][15][16][17]. However, the Al layer in TBCs as bonding interlayer between TBCs (8YSZ top coat and MCrAlY bond coat) and Mg alloy substrate has not been investigated.…”

Section: Introductionmentioning

confidence: 99%

Preparation and Bond Properties of Thermal Barrier Coatings on Mg Alloy with Sprayed Al or Diffused Mg-Al Intermetallic Interlayer

et al. 2013

View full text Add to dashboard Cite

Sprayed Al or diffused Mg-Al layer was designed as interlayer between the thermal barrier coatings (TBCs) and Mg alloy substrate. The effects of the interlayer on the bond properties of the coats were investigated. Al layers were prepared by arc spraying and atmospheric plasma spraying (APS), respectively. Mg-Al diffused layer was obtained after the heat treatment of the sprayed sample (Mg alloy with APS Al coat) at 400°C. The results show that sprayed Al interlayer does not improve the bond stability of TBCs. The failure of the TBCs on Mg alloy with Al interlayer occurs mainly due to the low strength of Al layer. Mg-Al diffused layer improves corrosion resistance of substrate and the bond interface. The TBCs on Mg alloy with Mg-Al diffused interlayer shows better bond stability than the sample of which the TBCs is directly sprayed on Mg alloy substrate by APS.

show abstract

Corrosion resistance of thermally sprayed Al and Al/SiC coatings on Mg

Cited by 109 publications

References 9 publications

Electrochemical Behavior of Bilayer Thermal-Spray Coatings in Low-Temperature Corrosion Protection

Electrochemical Behavior of Bilayer Thermal-Spray Coatings in Low-Temperature Corrosion Protection

Superplastic behavior of Al-coated Mg alloy sheet

Preparation and Bond Properties of Thermal Barrier Coatings on Mg Alloy with Sprayed Al or Diffused Mg-Al Intermetallic Interlayer

Contact Info

Product

Resources

About