Electrodeposition of Copper and Brass Coatings with Olive-Like Structure

One method of creating a brass coating is through electrodeposition, which is most often completed in cyanide galvanic baths. Due to their toxicity, many investigations focused on the development of more environmentally friendly alternatives. The purpose of the study was to explore a new generation of non-aqueous cyanide-free baths based on 1-ethyl-3-methylimidazolium acetate ionic liquids. The study involved the formation of copper, zinc, and brass coatings. The influence of the bath composition, cathodic current density, and temperature was determined. The obtained coatings were characterized in terms of their morphology, chemical composition, phase composition, roughness, and corrosion resistance. It was found that the structure of the obtained coatings is strongly dependent on the process parameters. The three main structure types observed were as follows: fine-grained, porous, and olive-like. To the best knowledge of the authors, it is the first time the olive-like structure was observed in the case of an electrodeposited coating. The Cu-Zn coatings consisted of 19–96 at. % copper and exhibited relatively good corrosion resistance. A significant improvement of corrosion properties was found in the case of copper and brass coatings with the olive-like structure.

Electrodeposition of Copper and Brass Coatings with Olive-like Structure

One method of creating a brass coating is through electrodeposition, which is most often completed in cyanide galvanic baths. Because of the toxicity of cyanides, many are working on the development of cyanide-free baths, which are promising but not satisfactory to replace the classic methods. The purpose of the study was to explore a new generation of non-aqueous cyanide-free baths based on 1-ethyl-3-methylimidazolium acetate ionic liquids. The study involved the formation of copper, zinc, and brass coatings. The influence of the bath composition, cathodic current density, and temperature was determined. The obtained coatings were characterized by their morphology, chemical composition, roughness, and corrosion resistance. It was found that the structure of the obtained coatings is strongly dependent on the process parameters. The three main structures observed were fine-grained, porous, and olive-like. To the best knowledge of the authors, it is the first time the olive-like structure was observed in the case of an electrodeposited coating. The Cu-Zn coatings consisted of 19–96 at.% copper and exhibited relatively strong corrosion resistance. High improvement of corrosion properties was found in the case of copper and brass coatings with an olive-like structure.

Effects of number of substituents and molecular weight of polyamines on the non-cyanide alkaline zinc plating process

The effects of the number of substituents and molecular weight of polyamines in the non-cyanide alkaline plating bath on the morphology, brightness and bright ranges of zinc electrodeposited coating and cathodic polarization, cyclic voltammogram on the non-cyanide alkaline zinc plating process were investigated. Cathodic polarization measurements showed that the polyamines all increased cathodic polarization of the plating process and shifted the zinc reduced potential to a more negative direction. However, cycle voltammogram curves of the 5 continuous cycles shows that the quaternary polyamine Q7-20 has a more stable adsorption and desorption processes than the secondary polyamine Bt18 has.

The Effect of Accelerator Types on the Phosphate Zn-%12Ni Electrodeposited Coating

The aim of this study is to investigate the effect of nitrate and nitrite on the weight, morphology and electrochemical properties of phosphated Zn-%12Ni electrodeposit coatings. In order to investigate phase structure and surface morphology of samples, X-ray diffraction and scanning electron microscopy were employed. In order to measure corrosion resistance behavior of the coats, Potentiostat/Galvanostat test was used. The results showed that nitrite accelerator reduces coating weight and surface porosity simultaneously obtaining by phosphating solution. Furthermore, coatings which were obtained by the nitrite accelerator had a higher corrosion resistance than that of the nitrate accelerator.

Tribological Study of Fe–W–P Electrodeposited Coating on 316 L Stainless Steel

Ternary iron–tungsten–phosphorus (Fe–W–P) coatings were electrodeposited with different sodium tungstate (NaWO4·2H2O) concentration on stainless steel 316 L substrate. These coatings were characterized by energy dispersive X-ray spectrometer (EDX), scanning electron microscope (SEM), and X-ray diffraction (XRD). The friction and wear behavior of these coatings were investigated using ball-on-disk tribometer under dry conditions. This study reveals a nanocrystalline and nodular structure with nanometric grain size of the deposited alloy. The maximum level of incorporation of tungsten (W) is about 29.54 at %. It was obtained with 0.5 M of sodium tungstate concentration, and it increases the microhardness of the coatings. Moreover, it was found that Fe–W–P coatings had significantly improved the tribological properties of the substrate due to their higher wear resistance and lower friction coefficient.

Graphene/polyaniline electrodeposited needle trap device for the determination of volatile organic compounds in human exhaled breath vapor and A549 cell

In this work, a graphene/polyaniline (G/PANI) electrodeposited coating was introduced as a novel extraction phase of needle trap microextraction (NTME) for the extraction of volatile organic compounds (VOCs).