Research Paper Replacement of Copper Cyanide by Copper Sulfate In

Research Paper

Replacement of copper cyanide by copper sulfate in brass electroless bath

Accepted 20th April, 2019

ABSTRACT

Environmental friendly processes and health protection are industrial requirements nowadays. In the surface finishing industry, there are greater opportunities for the improvement of the composition of bath solutions, reduction or elimination of the use of toxic substances, and the formation of residues with high complexity for your disposal. This study presents results on the replacement of copper cyanide by copper sulfate in the composition of an electroless brass plating bath; this electroless brass plating process can be applied directly to zamak alloys, low-carbon steels, or aluminum. The effect of the concentration of copper Gladis P. Mendoza-Aragón, Roal Torres- Sánchez, Adan Borunda-Terrazas, Alfredo sulfate on the morphological and brass film color characteristics was studied. For Aguilar-Elguézabal and Carlos Domínguez- this purpose, the characterization was done by scanning electron microscopy, Ríos* optical microscopy, and L*, a*, b*color parameters using spectrophotometry and electrochemical techniques. The composition of the bath consists of zinc oxide as a Centro de Investigación en Materiales +2 Avanzados, S.C., Miguel de Cervantes No. 120, source of Zn ions, a suitable complexing agent, and a stabilizer, under alkaline pH Complejo Industrial Chihuahua, Chihuahua, and temperature of 75±C. The results indicate that it is possible to control the México C.P. 31136. color of brass plating through this new process by selecting the Cu+2/Zn+2 ratio.

*Corresponding author. E-mail: [email protected]. Tel: 52 614 Key words: Brass, electroless, cyanide, sulfate, electrochemical, zamak, 4391117. spectrophotometer, copper.

INTRODUCTION

Brass plating, which originated in the mid-1600s, is one of bumpers, application as lubricating film for the drawing of the processes most frequently used to coat alloys. The steel, and so on. Brass plating may be a potential substitute ancient process consists of the dissolution of solid brass in for dyes and resins applied electrolytically, a technology is nitric acid mixed with cyanide to prepare the plating bath, relatively new. Although the latter technology is gaining which is a health risk due to the obvious volatility of the some acceptance, commercial costs, difficult adaptability to substances used in this process. It was not until 1920 that high-volume processes, and the fact that the finish cannot the electrolytic process was developed as an alternative to rust or age artificially reduce its fields of application, so the use of solid brass (Kowalski, 1998). brass is an excellent substitute (Kowalski, 1998). The interest in brass coating focuses on two main areas: Baths for coating metal objects with brass by both functional and decorative. For decorative purposes, the electrolytic and electroless processes are based on the use brass coating is mainly applied to hardware. In this of copper cyanide, zinc cyanide, and sodium cyanide, these application, the colorof the brass is very important. processes are considered highly hazardous to health and Coatings are usually thin (0.005 mm) and the coating has highly toxic. Since cyanide-based precursor is still used, little protection against corrosion in harsh environments there is a great interest in replacing cyanide salts for the (Blum and Hogeboom, 1949; Strow, 2005). preparation of brass baths. Examples of functional purposes of brass plating include Attempts have been made to eliminate or reduce the use increasing the adhesion between rubber and steel, of cyanides in brass electrolytic baths and other types of improving the corrosion resistance of marine vessels, use in metal plating, such as silver coating (Sanchez et al., 1996), the automotive industry as an intermediate layer on where a low cyanide content is used in the bath, gold Academia Journal of Environmental Science; Mendoza-Aragón et al. 038

plating with thiosulfate instead of gold cyanides (Sullivan Hurtado-Macias et al., 2010; Domínguez-Ríos et al., 2005), it and Kohl, 1997), the use of a non-cyanide bath for was evaluated the effect of sodium-potassium tartrate on electroless gold plating on Ni substrates (Sato et al., 2002), the morphological characteristics and the Cu-Zn film and cyanide-free zinc plating (Nabil, 2002). Fujiwara and composition, obtaining an acicular morphology on deposits Enomoto (1988) developed a brass-plating bath free of with low levels of Rochelle salt and nodular morphology cyanides based on CuSO4, ZnSO4, and sodium with a high content of Rochelle salt in the bath. glucoheptonate dehydrate with pH above 10.0 using The process of this study was originally developed and current densities of 0–5 A/dm2. The thickness of the brass patented by our group using cyanide precursor film was 5–50 m. According to their results, the Cu7OZn3O (Domínguez-Ríos et al., 2008; Domínguez et al., 2001; brass characteristic color was obtained with current Hurtado-Macias et al., 2010; Domínguez-Ríos et al., 2005). densities above 1 A/dm2. There is a patent for cyanide-free In these studies, the bath composition contained ZnO, electroplating brass plating based on pyrophosphate and CuCN, NaCN, NaOH, Rochelle salt, and NH3OH-Na2CO3 to orthophosphate, with the application of a brass film with a adjust the pH. Due to environmental pressures and for thickness of 0.05 to 0.1 m on a metallic foil substrate toxicological reasons, we started a research in order to (Ameen and Orloff, 1998). Carlos and De Almeida (2004) replace CuCN by the environmentally friendly CuSO4. The studied the effect of polyalcohol sorbitol on an electrolytic process reported in this study concerns an electroless bath bath of Cu-Zn and reported the capability to obtain colors of that solves several problems that are present in the Cu-Zn deposit from golden to grayish bright brass. electroplating of brass. Studies on cyanide-free electrolytic Sn-Zn bath plating using sulfate-tartrates at pH from 4 to 5 have also been published (Guaus and Torrent-Burgués, 2005). Another EXPERIMENTAL research on the electroplating of Cu-Zn alloy in an alkaline solution by adding D-mannitol was reported (Juskenas et Samples of zamak alloy with dimensions of 20 mm × 20 mm al., 2007). De Almeida et al. (2011) studied electrolytic Cu- × 2 mm were used as a substrate. They were roughened Zn plating based on Ethylenediaminetetraacetic acid with 220 and 600 grit sandpapers and then weighed in (EDTA) as Cu2+complexing, a cyanide-free process with the groups of three pieces to start the process of electroless capability to obtain yellow brass color. Ballesteros et al. brass plating. Three samples were subjected to electroless (2014) studied the electrochemical deposition of Cu-Zn plating for each experimental condition. To properly using chloride of Cu and Znandglycine as complexing agent; prepare the surface of the pieces of zamakalloy for the this electrolytic bath was also free of cyanides and worked electroless brass, the following baths were prepared: at room temperature. Recently, Minggang et al. (2015) studied the influence of copper sulfate for electrolytic Cu-Zn a) Alkaline degreasing bath, which was prepared with plating in a cyanide-free bath using 1-hydroxyethylidene-1, Na2CO3 and Na3PO4-12H2O as recommended by ASTM 1-diphosphonic acid (HEDP), potassium citrate, Cu and Zn B252-92 (2009), a bath temperature of 70–85C, a current sulfates, and potassium hydroxide to adjust the pH to 13. density of 30–55 A/dm2, time of 180 s, and rinsing with Among the most recent efforts to apply a cyanide-free distilled water. Cu-Zn coating, we can review the study of Ramírez and b) A cathodic degreasing bath of sodium hydroxide (NaOH), Calderón (2016) who investigated several Cu and Zn bath which was used to complete the removal of oils and fats compositions using sulfates, triethanolamine as a chelating and to ensure good adhesion of the electroless brass plating agent, sodium hydroxide, and an alkaline pH of (ASTM B252-92, 2009). The conditions of the bath were approximately 14. It can have different compositions of the room temperature, a current density of 16 A/dm2, a time of Cu-Zn film and by controlling the amount of 40 s, and rinsing with distilled water. triethanolamine and the applied current density, a Cu7OZn3O coating could be obtained. After surface preparation, the next step was immersion in A comparative study of four N-based additives added to a the electroless brass plating bath, for which the content of plating bath of Cu-Zn-Sn with different amounts of CuSO4 was varied while keeping the concentration of the additives showed that it was possible to control the color of other reagents constant in accordance with our previous the alloy and obtain a color that imitated gold color. The studies (Domínguez-Ríos et al., 2008; Domínguez et al., four additives were triethanolamine (TEA), ammonium 2001; Hurtado-Macias et al., 2010; Domínguez-Ríos et al., fluoride (AF), ammonia triacetic acid (NTA), and 2005). The composition and conditions of the baths used in polyacrylamide (PAM). The color varied from a red to a the experiments are shown in Table 1. color that imitated gold, and Cu-Zn-Sn blackened coatings The surface characterization and measurement of the could be obtained by using a larger quantity of the additives thickness of the electroless brass coating was performed by (Ding et al., 2018). scanning electron microscopy (FSEM) using a Jeol JSM 7400 In previous studies on electroless brass plating on zamak instrument and the weight gain was calculated alloy (Domínguez-Ríos et al., 2008; Domínguez et al., 2001; gravimetrically. For measurement of the L*, a*, and b* color Academia Journal of Environmental Science; Mendoza-Aragón et al. 039

Table 1: Compositions and conditions of electroless baths.

Bath Reactant (mol/L) 1 2 3 4 5 6 7 NaOH 1.12 1.12 1.12 1.10 1.12 1.12 1.12 NaCN 1.50 1.50 1.50 1.50 1.50 1.50 1.50 ZnO 0.11 0.11 0.11 0.11 0.11 0.11 0.11

CuSO4 0.05 0.07 0.08 0.10 0.11 0.13 0.15

Na2CO3 0.20 0.20 0.20 0.20 0.20 0.20 0.20

NH4OH 0.16 0.16 0.16 0.16 0.16 0.16 0.16

NaK(C4H4O6)·4H2O 0.12 0.12 0.12 0.12 0.12 0.12 0.12

Bath Conditions Temperature (C) 70 70 70 70 70 70 70 Time (min.) 15–30 15–30 15–30 15–30 15–30 15–30 15–30 Agitation Cst. Cst. Cst. Cst. Cst. Cst. Cst. pH 11 11 11 11 11 11 11

Table 2: Weight gain and thickness of sample vs CuSO4 concentration.

Weight gain (mg) Thickness (µm) Bath 15 min 20 min 30 min 15 min 20 min 30 min 1 0.8 2.4 2.0 3.328 0.974 1.295 2 1.0 1.1 1.4 2.489 1.168 2.710 3 1.6 0.8 1.1 1.480 1.967 2.330 4 1.6 0.9 1.0 2.554 2.777 2.654 5 1.5 2.0 2.4 3.035 2.307 2.372 6 2.1 2.1 1.5 3.193 4.160 5.617 7 4.1 2.7 5.03 4.332 4.844 4.514

parameters, a Spectrum-one spectrophotometer gloss guide CuSO4 and a steady increase starts above 0.08 mole/L of 45/0 equipped with a spectre-guide sphere gloss (BYK CuSO4. As can be seen in Figure 1(b), the thickness of the Gardner) was used. A Gill AC potentiostat-galvanostat from brass layer obtained with the highest CuSO4 concentration ACM Instruments was used for electrochemical is around 4 to 5 μm, providing evidence for the characterization. autocatalytic character of the electroless brass bath. Table 3 shows the results of variables that describe the color L*, a*, and b* when the content of copper sulfate RESULTS AND DISCUSSION increases in the bathroom. The letter L* correspond to the quantitative determination of clarity or whiteness of Table 2 shows the results of weight gain and brass coating, a* indicates a tendency toward red if its value is thickness coating for three immersion time conditions with positive or green if it is negative, and b* indicates the different contents of CuSO4 in the electroless brass plating tendency toward yellow if it is positive and blue if it is bath. negative. As can be seen, low dispersion of the b* Figure 1(a) shows a graph of the weight gain of the parameter is obtained by this process and the combination electroless brass film as a function of the concentration of of parameters L*, a*, and b*corresponds to a typical CuSO4. The highest weight gain is observed for the sample yellowish brass color. with an immersion time of 30 min and the highest Figure 2(a) shows the graph of L*, indicating that the concentration of CuSO4 (5.03 mg of brass coating). For all increase in copper sulfate content increases the whiteness samples, there is a trend of an increase in weight gain as the of the yellow color. Figure 2(b) shows that the parameter CuSO4 concentration increases, but for samples with a* maintains values below 10, indicating a tendency immersion times of 20 and 30 min, a high variability in towards reddish color, while Figure 2(c) shows that yellow weight gain is observed for the lower concentrations of color predominates as values of b* are above 25, and this Academia Journal of Environmental Science; Mendoza-Aragón et al. 040

Figure 1: Graphs of copper sulfate concentration vs (a) weight gain of the brass film and (b) thickness of brass film.

Table 3: Results of the L*, a*, b* System (corresponding to lightness, redness, and yellowness, respectively).

L* a* b* Bath 15 min 20 min 30 min 15 min 20 min 30 min 15 min 20 min 30 min 1 69.98 70.49 74.83 0.26 5.90 0.40 30.31 39.23 35.09 2 70.24 72.20 72.18 2.58 8.27 7.22 36.29 29.35 32.62 3 76.20 71.73 67.93 0.85 0.49 0.51 28.66 30.30 26.96 4 77.59 78.13 76.23 0.49 0.69 7.59 29.08 30.29 26.80 5 78.54 78.34 78.39 0.01 0.16 1.75 31.18 31.25 33.17 6 83.30 79.09 75.01 1.38 9.58 3.72 30.00 26.85 33.15 7 84.21 84.45 77.24 2.34 1.42 4.08 30.41 28.25 30.93

color is obtained even with low concentrations of CuSO4. growth of Zn needles is observed for the CuSO4 contents of Figure 3 shows the electroless brass film on the samples 0.05 and 0.150 mole/L. obtained with an immersion time of 15 min under different Figure 5 shows the surface morphology of the samples concentrations of CuSO4. As can be observed, for almost all with the immersion time of 30 min. As can be seen, they samples a nodular structure prevails, where each node has have a nodular structure with the cauliflower the appearance of a cauliflower form. For the CuSO4 content characteristic, but Zn needles are not present, which of 0.150 mole/L, a needle-type growth consisting of Zn is indicates that the coating mainly consists of brass. This observed, and the cauliflower structure can be observed in surface morphology can be associated with the low gloss of the background. For samples with immersion times of 20 the brass coating; however, the characteristic yellow color min, Figure 4 shows that the nodule size is smaller when of brass Cu7OZn3O is obtained. compared with the immersion time of 15 min; nevertheless, Figure 6 shows a micrograph of the cross-section of an the cauliflower structure is also seen in the nodules and the electroless brass film sample obtained with an immersion Academia Journal of Environmental Science; Mendoza-Aragón et al. 041

Figure 2: Graphs of L*, a*, b* system for definition of the color of the electroless brass film.

time of 30 min and a CuSO4 concentration of 0.13 mole/L. electroless bath with CuCN are shown, since all electroless As can be seen, there is excellent adhesion between the baths exhibit the same behavior. Autocatalytic reduction or brass film and zamak alloy and the film does not have pores electroless is a technique through which metal deposits are and is very homogeneous. By means of SEM equipped with obtained by a redox reaction, which occurs within the EDS, a microanalysis was carried out to determine the ratio solution between the metal ions to be deposited and the of Cu/Zn with increasing content of CuSO4. The results are reducing agent, without an external input current, and the shown in the graph in Figure 7; it can be observed that the coating process is autocatalytic, since once the metal begins ratio increases slightly with increasing content of CuSO4, to be deposited, it will be responsible for catalyzing the indicating that the deposition rate of Cu is directly reduction of more metallic ions present in the bath. Figure dependent on the CuSO4 concentration. 8(a) shows the behavior of potential (mV) versus time (s) For the electrochemical characterization of electroless of the two baths studied during 1800 s. It is observed that brass baths, the results of the bath containing a CuSO4 the electrochemical potential or redox presents a very concentration of 0.11 mole/Land a comparison with an similar behavior with the same tendency throughout the Academia Journal of Environmental Science; Mendoza-Aragón et al. 042

(a) (b)

(e) (f)

(g)

Figure 3: FESEM microphotographs of samples with immersion time of 15 min. under copper sulfate concentrations of a) 0.050, b) 0.067, c) 0.084, d) 0.100, e) 0.117, f) 0.134, and g) 0.150 mol/L.

Academia Journal of Environmental Science; Mendoza-Aragón et al. 043

(a) (b)

(e) (f)

(g)

Figure 4: FESEM microphotographs of samples with immersion time of 20 min. under copper sulfate concentrations of a) 0.050, b) 0.067, c) 0.084, d) 0.100, e) 0.117, f) 0.134, and g) 0.150 mol/L.

Academia Journal of Environmental Science; Mendoza-Aragón et al. 044

(a) (b)

(e) (f)

(g)

Figure 5: FESEM microphotographs of samples with immersion time of 30 min. under copper sulfate concentrations of a) 0.050, b) 0.067, c) 0.084, d) 0.100, e) 0.117, f) 0.134, and g) 0.150 mol/L.

Academia Journal of Environmental Science; Mendoza-Aragón et al. 045

Brass Film electroless Zamack Alloy

Figure 6: FESEM microphotographs of a cross-section of the sample with an immersion time 30 min. and a CuSO 4 concentration of 0.13 mole/L.

Figure 7: Graph Cu/Zn ratio obtained from EDS microanalysis.

test time, initiating the process with potential values of approximately –0.6 mA/cm2. This latter trend is indicative about –1510 mV and ending in values close to -1375 mV. of the consumption of reducing species. On the other hand, The behavior shown in both cases may be associated with the test with CuCN presents large positive values of the both the anodic and cathodic reactions, which are carried current in the first few seconds, with predominant out simultaneously in the process, and have very similar oxidizing species, but those values immediately become potentials; that is, the oxidation and reduction potentials negative, indicating the presence of the reducing species (a maintain very close values in both tests. A shift of the curve greater amount of metal ions are present in the bath), is observed for the bath with CuCN, indicating that the showing a similar decrease in these values, in the same way potential is more negative, which indicates the possibility of as the tendency shown in Test 05. The behavior shown in having a more negative potential in the reducing agent, both tests must influence the quality of the coating, causing an increase of the kinetics reduction. Figure 8(b) adhesion, compactness, continuity, and number of pores. shows the behavior of the current density (mA/cm2) versus In both tests, descending peaks are observed, which are time (s) for an electroless brass bath containing a CuSO4 known as transient or anodic and cathodic peaks. This concentration of 0.11 mol/L as compared with an behavior can be observed in both the potential series and electroless bath with CuCN. The behavior shown for the the current series, between which there exists a reciprocity CuSO4 bath (Test 05) starts with positive values current according to Ohm’slaw, indicating abrupt changes in both until a time of 300 s, showing that there is a prominent potential and current demand. presence of oxidizing species (reducing agent) at the start According to information obtained from the literature of the process and thereafter a current change to negative regarding both electrolytic and electroless individual values (with reducing species with CuSO4), reaching a processes and taking into account all the results obtained in maximum value of approximately –0.9 mA/cm2 in about this study, we propose the following mechanisms based on 700 s. Departing from this value, a downward trend is the similarities of reagents in electroless plating baths and observed until the end of the test, reaching a value of electrolytic baths. The surface to be covered with brass Academia Journal of Environmental Science; Mendoza-Aragón et al. 046

(a)

(b)

Figure 8: Graphs of electroless brass bath (a) potential vs time and (b) current vs time for bath 5 and bath with CuCN.

must be a surface with catalytic sites; thus once the metallic Furthermore, NaCN is added to the bath as a stabilizing surface has been immersed in the electroless brass plating component, and the dissolved oxygen in the bath reacts bath, the reducing agent (R-) in contact with the catalytic with hydrocyanic acid to produce cyanate ions according to surface (Figure 9(a)) will begin to be oxidized (R+), as Reaction 3 (Saubestre, 1972): indicated in Figure 9(b). While the liberated electrons will - - - remain on the catalytic surface, promoting the interaction 2 CN + O2 2 OCN + 4e ...... 3 of copper and zinc ions with those electrons on the surface, thus starting the deposition of brass, as shown in Figure According to the literature (ASTM B252-92, 2009)., 9(c). The fresh brass surface formed becomes the new Rochelle salt acts as a reducing agent according to the autocatalytic surface and keeps growing until the Cu and Zn following reaction: ions have been totally consumed. The following chemical 2- - reactions are involved: C4H4O6 + O2 4CO2 + 2H2 + 2 e ...... 4

2+ +1 +1 KNaC4H4O6 + Cu Cu(C4H4O6) + K + Na in solution ...... 1 Finally, with the excess of free electrons found in the bath and the catalytic surface of the part, the brass alloy is In strongly alkaline solutions, the zinc forms the deposited on the surface: tetrahydroxozincate: Cu2+ + 2e-Cu° 2+ - 23- 2+ - Zn + 4 OH Zn(OH)4 also in solution ...... 2 Zn + 2e Zn° Finally, with the excess of free electrons found in the bathand the catalytic surface of the part, the brass alloyis deposited on the surface.

Cu2+ + 2e-Cu° Academia Journal of Environmental Science; Mendoza-Aragón et al. 047 2+ - Zn + 2e Zn°

(a) Brass Cu+2 (b) Brass Cu+2 electroless R- electroless e- R+ R+ bath +2 bath +2 R- Zn e- Zn Cu+2 Cu+2 Zamak R- Zamak e- R+ alloy alloy R+ R- Cu+2 e- Cu+2 Zn+2 Zn+2 R- e- + - - R R+ R Cu+2 e Cu+2 Cu+2 Cu+2 R- e- - - R+ + R Zn+2 e R Zn+2 +2 +2 R- Zn e- Zn R- e- R+ +2 Cu+2 +2 Cu+2 R- Cu e- Cu R- e- R+

Brass +2 (c) electroless - Cu bath e e- Cu+2 Zamak e- alloy e- Zn+2 e- e- Cu+2 e- e- +2 e- Zn

Brass e- coating +2 e- Cu e-

Figure 9: Electroless brass deposition mechanism on the zamak alloy surface: (a) initial reaction on the Figure 9. Electrolesscatalytic surface ofbrass zamak , deposition(b) oxidation reaction mechanism of the reducing on agent the on zamak the surface alloy of zamak, surface: and (c) (a) initial reduction and brass alloy coating on the surface of zamak. reaction on the catalytic surface of zamak, (b) oxidation reaction of the reducing agent on the surface of zamak, and (c) reduction and brass alloy coating on the surface of Conclusions Ballesteros JC, Torres-Martínez LM, Juárez-Ramírez I, Trejo G, Meas Y 2+ 2+ zamak.(2014). Study of the Electrochemical Co-Reduction of Cu and Zn Ions from an Alkaline Non-Cyanide Solution Containing Glycine. J. According to our results, copper cyanide can be replaced by Electroanal. Chem. 727: 104–112. copper sulfate in the electroless brass bath and the Blum W, Hogeboom GB (1949). Principles of Electroplating and deposition rate is maintained. This substitution allows the Electroforming, third edition, McGraw-Hill. use of environmentally friendly brass plating, since Carlos A, De Almeida MRH (2004). Study of the Influence of the Polyalcohol Sorbitol on the Electrodeposition of Copper-Zinc Films from wastewater is more simplified. a Non-Cyanide Bath. J. Electroanal. Chem. 562(2): 153–159. The surface morphology of the electroless brass film is De Almeida MRH, Barbano EP, de Carvalho MF, Carlos IA, Siqueira JLP, nodular with cauliflower-shaped nodules. This process Barbosa LL (2011). Electrodeposition of Copper–Zinc from an Alkaline allows the tuning of color by selection of the brass Bath Based on EDTA. Surf. Coat. Technol. 206(1): 95–102. Ding L, Liu F, Cheng J, Niu Y (2018). Effects of four N-based additives on relationship CuSO4/ZnO, including the yellow brass color imitation gold plating. Journal of Applied Electrochemistry, Published Cu7OZn3O. online 13 January 2018, https://doi.org/10.1007/s10800-018-1148-8. Domínguez C, MV Moreno A (2001). Aguilar-Elguézabal, Process for Autocatalytic BrassPlating on Zamak Alloys. Plating Surf. Finishing. 88(9): 91–99. ACKNOWLEDGMENT Domínguez-Ríos C, Moreno López MV, Miranda Navarro SV (2005). Mejoras al proceso de latonado por inmersión para piezas de aleaciones The authors are grateful to Wilber Antúnez for his valuable base zinc, Mexican Patent No. MX 229,256. assistance with the scanning electron microscopy. Domínguez-Ríos C, Moreno MV, Torres-Sánchez R, Antúnez W, Aguilar- Elguézabal A, González-Hernández J (2008). Effect of Tartrate Salt Concentration on the Morphological Characteristics and Composition of Cu-Zn electroless plating on Zamak 5 zinc alloy. Surf. Coat. Technol. REFERENCES 202(19): 4848–4854. Fujiwara Y, Enomoto, H (1988). Characterization of Cu-Zn Alloy Deposits Ameen TJ, Orloff GL (1998). Non-Cyanide Brass Plating Bath and a Method from Glucoheptonate Baths. Surf. Coat. Technol. 35(1): 113–124. of Making MetallicFoil Having a Brass Layer Using the Non-Cyanide Guaus E, Torrent-Burgués J (2005). Tin–Zinc Electrodeposition from Brass PlatingBath, Patent USA No. 5762778 A. Sulphate–Tartrate Baths. J. Electroanal. Chem. 575(2): 301–309. Academia Journal of Environmental Science; Mendoza-Aragón et al. 048

Hurtado-Macias A, Domínguez-Ríos C, Muñoz-Saldaña J, Torres-Sánchez R, Sato J, Kato M, Otani H, Homma T, Okinaka Y, Osaka T, Yoshioka O (2002). Pérez-García SA, González-Hernández J (2010). Effect of Surface Substrate Ni Catalyzed Electroless Gold Deposition from a Noncyanide Substrate Roughness and of Chelating Agent on the Microstructure and Bath Containing Thiosulfate and Sulfite. J. Electrochem. Soc. 149(3): Mechanical Properties of Electroless Processed Brass Coatings. Ind. Eng. C168-C172. Chem. Res. 49(24): 6388–6393. Saubestre EB (1972). Stability of electroless copper solutions. Plating. 59: Juskenas R, Karpavičienė V, Pakštas V, Selskis A, Kapočius V (2007). 563- 566. Electrochemical and XRD Studies of Cu–Zn Coatings Electrodeposited in Standard Guide for Preparation of Zinc Alloy Die Casting for Electroplating Solution with D-mannitol. J. Electroanal. Chem. 602(2): 237–244. and Conversion Coatings, Active Standard ASTM B 252-92 (2009), Book Kowalski AJ (1998). Brass plating. Plating Surf. Finishing. 85(36). of Standards, vol. 02.05. Martyak NM, McDuffie B (1990). Side Reactions in Electroless Copper, Part Strow H (2005). Surface Engineering, vol. 5, ASM Handbook. I.Distillation of Ammonia. Metal Finishing. 88: 51-54. Sullivan M, Kohl PA (1997). Electrochemical Study of the Gold Thiosulfate Minggang L, Guoying W, Shuangshuang H, Shuhan X, Yejiong Y, Qinfang M Reduction. J. Electrochem. Soc. 144(5): 1686-1690. (2015). Electrodeposition of CuZn Alloys fromthe Non-Cyanide Alkaline Bath, Surf. Rev. Lett. 22: 1550003-1–1550003-6. Nabil Z (2002). High Performance Alkaline Cyanide-Free Zinc Plating Carbon Rich Deposit, AESF SUR/FIN® Proceedings. pp. 638–647. Cite this article as:

Ramírez C, Calderón JA (2016). Study of the effect of Triethanolamine as a Mendoza-Aragón GP, Torres-Sánchez R, Borunda-Terrazas A, chelating agentin the simultaneous electrodeposition of copper and Aguilar-Elguézabal A, Domínguez-Ríos C (2019). Replacement of zincfrom non-cyanide electrolytes. J. Electroanal. Chem. 765: 132–139. copper cyanide by copper sulfate in brass electroless bath. Acad. J. Sanchez H, Chainet E, Nguyen B, Ozil P, Meas Y (1996). Electrochemical Environ. Sci. 7(4): 037-048. Deposition of Silver from a Low Cyanide Concentration Bath. J.

Electrochem. Soc. 143(9): 2799-2804. Submit your manuscript at

http://www.academiapublishing.org/journals/ajes