ALUMINUM DEPOSITS ON 42CD4 STEEL SUBSTRATES BY MOLTEN-SALTS ELECTROLYSIS

ALUMINUM DEPOSITS ON 42CD4 STEEL SUBSTRATES BY MOLTEN-SALTS ELECTROLYSIS

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Title

ALUMINUM DEPOSITS ON 42CD4 STEEL SUBSTRATES BY MOLTEN-SALTS ELECTROLYSIS (EN)

Creator

GREGOIRE, L (EN)

CHRYSSOULAKIS, Y (EN)

KALOGEROPOULOU, S (EN)

MOORTGAT, G (EN)

Type

journalArticle (EN)

Partial document
Publication in journal (EN)

Article
Scientific article (EN)

Issued

2014-03-01T01:42:02Z

1993 (EN)

Year

1993 (EN)

Description

Electrolytic deposition of aluminum on 42CD4 steel substrates, from a KCl-LiCl eutectic melt with AlCl3 additions at 600-degrees-C, has been studied in order to improve surface properties and corrosion resistance under aggressive gaseous atmospheres. A detailed study of the aluminum reduction mechanism was carried out using the electrochemical methods of linear sweep voltammetry, cathodic chronopotentiometry and cathodic chronoamperometry. The solid state diffusion coefficient of the aluminum into the steel substrate was evaluated using cathodic chronoamperometry and was found to be D(Al) = 1.8 x 10(-11) cm2/sec. From the mechanism found by the electrochemical reaction study, the experimental parameters could be adjusted in order to obtain in a reproducible way a homogeneous, aluminum-rich surface layer of regular thickness on steel electrodes. The best results were obtained using square wave pulses with the following set of parameters: pulse amplitude i(p) = -80 mA/cm2, pulse duration t(p) = 0.5 sec, and relaxation time t(r) = 2 sec. Electron microprobe analysis showed that the electrodeposits obtained consisted of the solid compound, Fe2Al5. Microhardness measurements of the electrocoated samples showed that their superficial microhardness, as much as 950 Vickers, was improved compared to samples treated by classical methods (650 to 750 Vickers), such as nitriding, boriding or carburizing. (EN)

Scientific field

Materials Science, Coatings & Films (EN)

Metallurgy & Metallurgical Engineering (EN)

Engineering and Technology ▶ Materials Engineering
Surfaces, Coatings and Films (EN)

Engineering and Technology ▶ Materials Engineering
Metallurgy and Metallurgical Engineering (EN)

Subject

PULSATING CURRENT (EN)

SWEEP VOLTAMMETRY (EN)

CURRENT METAL ELECTRODEPOSITION (EN)

FUNDAMENTAL-ASPECTS (EN)

Journal

PLATING AND SURFACE FINISHING (EN)