The Effects of Na2SiO3 Concentration on the Properties of Plasma Electrolytic Oxidation Coatings on 6060 Aluminum Alloy

Becerik, D. Alexandre; Ayday, Aysun; Kumruoğlu, Levent Cenk; Kurnaz, S. Can; Ozel, A.

doi:10.1007/s11665-011-0022-1

Cited by 23 publications

(9 citation statements)

References 15 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Different electrolytes result in different growth rates, structures, phase compositions and element distribution of the PEO coatings [22][23][24][25]. Generally, the electrolytes used for PEO treatment are composed of acidic electrolytes and alkaline electrolytes.…”

Section: Influence Of Electrolytesmentioning

confidence: 99%

Plasma Electrolytic Oxidation Coatings on Lightweight Metals

Li¹,

Liang²,

Wang³

2013

Modern Surface Engineering Treatments

View full text Add to dashboard Cite

Section: Influence Of Electrolytesmentioning

confidence: 99%

Plasma Electrolytic Oxidation Coatings on Lightweight Metals

Li¹,

Liang²,

Wang³

2013

Modern Surface Engineering Treatments

View full text Add to dashboard Cite

“…The presence of elements such as Mg, Cu or Zn suppresses the transition from γ-to α-alumina, which again leads to a decreased hardness [10,11]. Nevertheless, all these phases exhibit a significantly higher hardness compared to the substrate [12][13][14] and also compared to oxide coatings produced by anodising or hard-anodising. The high hardness, residual compressive stresses in the oxide coating [15], and the compact microstructure of the oxide coatings produced by PEO lead to a high wear resistance [12,16,17].…”

Section: Introductionmentioning

confidence: 99%

Plasma Electrolytic Oxidation of High-Strength Aluminium Alloys—Substrate Effect on Wear and Corrosion Performance

Sieber

Simchen

Morgenstern

et al. 2018

Metals

View full text Add to dashboard Cite

Abstract:With the progress in materials science and production technology and the establishment of light-weight design in many fields of the industry, the application of light metals no longer requires only mechanical strength, but also a significant protection of the material against wear and corrosion. Hard and wear-resistant oxide coatings on aluminium are produced by plasma electrolytic oxidation (PEO). During PEO, a conversion of the aluminium substrate to a ceramic oxide takes place. While the role of strength-giving alloying elements like Cu, Mg/Si, Zn, and Zn/Cu on the PEO process has selectively been subject of investigation in the past, the significance of the alloy composition for the service properties of the coatings is still unknown. Therefore, the performance of PEO coatings produced on the widely used commercial high-strength alloys AlCu4Mg1 (EN AW-2024), AlMgSi1 (EN AW-6082), and AlZn5.5MgCu (EN AW-7075) is examined with regard to their behaviour in the rubber-wheel test according to ASTM G65 and the current density-potential behaviour of the substrates with undamaged and worn coatings in dilute NaCl solution. To give a reference to the unalloyed material the testings were carried out also on Al 99.5 (EN AW-1050) which was treated in an adjusted PEO process. Although differences in the conversion of intermetallic phases during PEO and the phase composition of the coatings on the various substrates are determined, the service properties are hardly depending on the alloying elements of the investigated aluminium materials. The wear rates in the rubber-wheel test are low for all the alloyed samples. The current density-potential curves show a decrease of the corrosion current density by approximately one order of magnitude compared to the bare substrate. Eventually, previous wear of the coatings does not deteriorate the corrosion behaviour. PEO layers on technically pure aluminum can resist the testing regimes if they are prepared in an electrolyte with an elevated silicate content and without additional hydroxide ions, during a longer process time.

show abstract

“…Chen et al [10] observed that the degree of polymerization of silicate ions, which influences the mechanism of coating formation, and the thermal-driven gel-forming process under sparking, depend on the concentration of NaOH and Na 2 SiO 3 . A wide range of Na 2 SiO 3 (2-36 g•L −1 ) and KOH or NaOH (2-8 g•L −1 ) concentrations were used in the electrolytic solution for PEO of Al alloy [7,[11][12][13][14][15][16]. Cheng et al [7] prepared PEO coating in dilute (8 g L −1 Na 2 SiO 3 •9H 2 O) and concentrated (36 g L −1 Na 2 SiO 3 •9 H 2 O) silicate solutions, and observed that the coatings formed in the dilute solution provided better wear resistance than those formed in the concentrated solution, due to better mechanical properties of the outer layer, and fine bonding of the layers.…”

Section: Introductionmentioning

confidence: 99%

Silicate and Hydroxide Concentration Influencing the Properties of Composite Al2O3-TiO2 PEO Coatings on AA7075 Alloy

et al. 2021

View full text Add to dashboard Cite

This work evaluates the effect of sodium meta-silicate pentahydrate (SMS) and potassium hydroxide concentrations on properties of Al2O3-TiO2 coatings produced through plasma electrolytic oxidation in a solution containing 3 g L−1 potassium titanyl oxalate, (PTO), using a unipolar waveform with constant current density. The surface and cross-section characteristics of PEO coatings including morphology, elemental distribution, and phase composition were evaluated using FESEM, EDS, and XRD techniques. Voltage-time response indicated the concentration of SMS and KOH had a significant effect on the duration of each stage of the PEO process. More cracks and pores were formed at the higher concentrated solutions that resulted in the incorporation of solution components especially Si into the coating inner parts. Ti is distributed throughout the coatings, but it had a dominant distribution in the Si-rich areas. The coating prepared in the electrolyte containing no silicate consisted of non-stoichiometric γ-Al2O3 and/or amorphous Al2O3 phase. Adding silicate into the coating electrolyte resulted in the appearance of α-Al2O3 besides the dominant phase of γ-Al2O3. The corrosion behaviour of the coatings was investigated using the EIS technique. It was found that the coating prepared in the presence of 3 g L−1 SMS and 2 g L−1 KOH, possessed the highest barrier resistance (~10 MΩ cm2), owing to a more compact outer layer, thicker inner layer along with appropriate dielectric property because this layer lacks the Si element. It was discovered that the incorporation of Ti4+ and especially Si4+ in the coating makes the dielectric loss in the coating.

show abstract

The Effects of Na2SiO3 Concentration on the Properties of Plasma Electrolytic Oxidation Coatings on 6060 Aluminum Alloy

Cited by 23 publications

References 15 publications

Plasma Electrolytic Oxidation Coatings on Lightweight Metals

Plasma Electrolytic Oxidation Coatings on Lightweight Metals

Plasma Electrolytic Oxidation of High-Strength Aluminium Alloys—Substrate Effect on Wear and Corrosion Performance

Silicate and Hydroxide Concentration Influencing the Properties of Composite Al2O3-TiO2 PEO Coatings on AA7075 Alloy

Contact Info

Product

Resources

About