corrosion resistance of as-plated and heat …mit.imt.si/revija/izvodi/mit175/yuksel.pdf ·...

B. YÜKSEL et al.: CORROSION RESISTANCE OF AS-PLATED AND HEAT-TREATED ELECTROLESS ...837–842

CORROSION RESISTANCE OF AS-PLATED AND HEAT-TREATEDELECTROLESS DUBLEX Ni-P/Ni-B-W COATINGS

KOROZIJSKA ODPORNOST PLATIRANIH IN NEELEKTRI^NOTOPOLOTNO OBDELANIH DUPLEKS Ni-P/Ni-B-W PREVLEK

Behiye Yüksel1, Garip Erdogan2, Fatih Erdem Bastan2, Rasid Ahmed Yýldýz3

1Istanbul Aydin University, Mechanical Engineering Department, 34668 Istanbul, Turkey2Sakarya University, Engineering Faculty, Department of Metallurgy and Materials Engineering, 54187 Sakarya, Turkey

3TU Istanbul, Mechanical Engineering Faculty, 34437 Istanbul, [email protected]

Prejem rokopisa – received: 2016-10-20; sprejem za objavo – accepted for publication: 2017-03-10

doi:10.17222/mit.2016.304

In this study, Ni-P/Ni-B-W dublex coatings were deposited on carbon steel substrates (AISI 1020) using the electroless platingprocess and their microstructure and corrosion properties were systematically evaluated based on different heat-treatmenttemperatures. Both, the surface morphology and cross-sectional morphology of the Ni-P/Ni-B-W coatings were studied using ascanning electron microscope (SEM), while X-ray diffraction (XRD) was applied for examining the structural modifications.The amorphous coating began to crystallize at a heat-treatment temperature of 350 °C. Potentiodynamic polarizationmeasurements were carried out in an aqueous medium containing 3.5 % NaCl for evaluating the corrosion resistance ofas-plated and heat-treated dublex coatings. The corrosion potentials of dublex coatings were observed to shift toward morepositive values with increased heat-treatment temperatures. Depending on the heat-treatment temperature, it was identified thatthe crystallized dublex coatings generally had better corrosion resistance than the amorphous coating.

Keywords: Ni-P/Ni-B-W coating, corrosion, heat treatment

V {tudiji so bile dvojne Ni-P/Ni-B-W prevleke nane{ene na substrate iz ogljikovega jekla (AISI 1020) s postopkom neelek-tri~nega platiranja. Sistemati~no so bile ocenjene mikrostruktura ter korozijske lastnosti izdelanih prevlek, glede na razli~netemperature toplotne obdelave. Morfologije povr{in in profili izdelanih Ni-P/Ni-B-W prevlek so bili pregledani z vrsti~nimelektronskim mikroskopom (SEM), medtem ko so bile z rentgensko difrakcijsko analizo (XRD) ugotovljene strukturnespremembe. Amorfna prevleka je za~ela kristalizirati pri temperaturi toplotne obdelave 350 °C. Korozijska odpornost platiranihin toplotno obdelanih dupleks prevlek je bila ocenjena s pomo~jo meritev potenciodinami~ne polarizacije v 3,5 % vodni razto-pini NaCl. Opazovali so korozijske potenciale dupleks prevlek, da bi dobili bolj pozitivne vrednosti z zvi{animi temperaturamitopolotne obdelave. Ugotovljeno je bilo, da imajo kristalizirane dupleks prevleke na splo{no bolj{o korozijsko odpornost kotamorfne prevleke.

Klju~ne besede: Ni-P/Ni-B-W dvojna prevleka, korozija, toplotna obdelava

1 INTRODUCTION

Studied for the first time in 1946 by Brenner andRiddell, the electroless plating process has been used inmany industrial applications because of its superiorcharacteristics over electroplating, such as the ability toplate insulation materials and having a homogeneouscoating-thickness distribution.1 Among electroless coat-ing types, electroless nickel coating is the most popularfor having good hardness, wear and corrosion resistanceproperties.2 If the electroless Ni coating family is re-viewed, besides pure Ni coatings, Ni-P and Ni-B coat-ings deposited using reducing agents such as hypo-phosphite, borohydride or dimethylamine borane standout. The major advantages of Ni-P coatings are their lowcost, high corrosion resistance and easy process control.3

Nonetheless, a borohydride reduced nickel coating isharder and has higher wear resistance than tool steel andhard chrome coatings.4,5 On the other hand, some studies– although they are limited in number – have highlightedthe addition of tungsten to this coating system for in-

creasing its corrosion resistance, which is lower than thatof a Ni-P coating.6–9 As a result of the co-deposition ofthis refractory material (which cannot be reduced in anaqueous solution as metallic tungsten) together with irongroup metals, developing coatings with attractive corro-sion and tribological properties is possible.10–12 Recently,research for obtaining multilayer coatings to increaseexisting coating corrosion resistance to higher levels hasalso been conducted.13,14

The aim of the present study was to evaluate theeffect of different heat-treatment temperatures on themicrostructure and corrosion properties of electrolessNi-P/Ni-B-W coatings. To the best of our knowledge, noothers studies are available on this topic.

2 EXPERIMENTAL PART

For this experiment, 10 mm × 10 mm × 60 mm plaincarbon steel (AISI 1020) plates were used as a substratematerial for developing Ni-P/Ni-B-W dublex coatings.Prior to the plating process, the surfaces of all the

Materiali in tehnologije / Materials and technology 51 (2017) 5, 837–842 837

MATERIALI IN TEHNOLOGIJE/MATERIALS AND TECHNOLOGY (1967–2017) – 50 LET/50 YEARS

UDK 620.193:621.78:669.058 ISSN 1580-2949Original scientific article/Izvirni znanstveni ~lanek MTAEC9, 51(5)837(2017)

samples were mechanically cleaned (up to 1200 grade)and then soaked in trichloroethylene and cleaned withdetergent in an ultrasonic bath at 70 °C. Finally, samplesurfaces were activated in 30 % of volume fractions. HClfor two minutes and then rinsed in distilled water. Thecleaned substrates were then soaked in Ni-P and Ni-B-Welectroless plating baths for two hours, respectively.

Reagent-grade chemicals and distilled water wereused for the preparation of all the electrolytes and the pHwas adjusted to 4.8±0.2 and 13.5±0.2 with H2SO4 orNaOH in Ni-P and Ni-B-W plating baths, respectively.The temperature of the baths was maintained at 90±2 °Cfor Ni-P and 88±2 °C for Ni-B-W.

Deposition of Ni-P and Ni-B-W was carried out in anaqueous bath containing 15 g/L NiSO4.6H2O, 26 g/LNa2H2PO2·H2O, 13 g/L NaC2H3O2, 12 mL/L HF and8 g/L NH4HF2 for the Ni-P coating, and 24 g/L NiCl2,60 mL/L EDTA, 26.5 g/L KOH, 120 g/L NaBH4,263 g/L NaOH, 2.6g/L PbWO4, 13 g/L EDTA and 40 g/LNa2WO4·2H2O for Ni-B-W coatings, respectively.

The coated specimens were heat treated at 250 °C,300 °C, 350 °C and 650 °C for 1 h each at a heating rateof 5 °C/min in an air-circulated furnace, followed byslow furnace cooling to room temperature.

The composition of the dublex coatings was deter-mined by energy-dispersive X-ray analysis (EDX) usinga Link Analytical QX-2000 attached to the SEM appa-ratus. The crystal structures of the dublex coatings wereexamined using a Philips PW 3710 grazing incidencex-ray diffractometer (Cu-K� radiation). A JeolJSM-7000F FE-SEM was used to characterize themicrostructures and morphology of the coatings. Thecorrosion behavior was investigated using a PGZ 301Dynamic Voltammetry and VoltaMaster4 software.

Electrochemical experiments were carried out in a3.5 % NaCl aqueous solution in a three-electrode cell atroom temperature. In this cell, a platinum electrode wasused as a counter electrode and a saturated calomelelectrode was used as a reference electrode; the dublexcoating was used as a working electrode and by masking

with silicon, only a 1 cm2 surface area was left on thesamples for exposure to the electrolyte. The dynamicpotential scanning technique was used for obtaining thepolarization curves of dublex coating samples. Prior tothe potentiodynamic measurement, samples were heldfor approximately 15 min in the electrolyte and thenelectrode potential was raised from -600mV to +200 mVat a rate of 10 mV/min.

3 RESULTS

The XRD patterns of the as-plated and heat-treatedNi-P/Ni-B-W coatings, and their chemical compositionsare in Figure 1 and in Table 1. SEM micrographs ofNi-P/Ni-B-W coatings before and after the heat treat-ments are in Figure 2.

Table 1: Chemical compositions of the Ni-P/Ni-B-W dublex coatings

Type ofcoating Ni (w/%) P (w/%) B (w/%) W (w/%)

Ni-P 87.27 12.73 - -Ni-B-W 87.45 - 7.86 4.69

B. YÜKSEL et al.: CORROSION RESISTANCE OF AS-PLATED AND HEAT-TREATED ELECTROLESS ...

838 Materiali in tehnologije / Materials and technology 51 (2017) 5, 837–842


Figure 2: Surface morphology of dublex coating a), b) as-platedNi-P/Ni-B-W, c) heat treated at 300 °C, d) heat treated at 650 °C

Figure 1: XRD spectra for a): as-plated Ni-P/Ni-B-W, b) 250 °C, c)300 °C, d) 350 °C and e) 650 °C

The cross-sections of the Ni-P/Ni-B-W dublex coat-ings are shown in Figure 3.

Potentiodynamic curves of as-plated and heat-treatedNi-P/Ni-B-W coatings at different temperatures obtainedin a 3.5 % NaCl aqueous medium are shown in Figure 4.

The changes in the corrosion current density (Icorr)values with heat treatment are given in Table 2.

Table 2: Corrosion resistance of as-plated and heat-treatedNi-P/Ni-B-W dublex coatings at different temperatures in 3.5 % NaClsolution

NiP/NiBW Icorr (μA/cm2) Ecorr (mV)As-plated 1.55±0.59 -506±32

300 °C 1.70±0.41 -470±23350 °C 0.71±0.20 -382 ±18650 °C 0.57±0.09 -280±11

The surface morphologies of the as-plated sampleand heat-treated sample at 650 °C following potentio-

dynamic polarization measurements are shown in Fig-ure 5.

The corrosion current density and corrosion potentialvalues obtained by Tafel interpolation are shown inTable 3.Table 3: Corrosion resistance of substrate and Ni-B-W andNi-P/Ni-B-W dublex coatings heat treated at 650 °C in 3.5 % NaClsolution

Sample Icorr (μA/cm2) Ecorr (mV)Carbon steel

substrate 4.59±1.01 -598±46

NiBW 3.40±0.35 -298±17NiP/NiBW 0.57±0.09 -280±11

Figure 6 shows the polarization curves of theNi-B-W and dublex Ni-P/Ni-B-W coatings heat treatedat 650 °C and the steel substrate obtained in a 3.5 %NaCl aqueous medium.

4 DISCUSSION

The Ni-P/Ni-B-W coating diffraction patterns up to300 °C reveal a single broad peak indicating an amor-phous coating structure under these conditions (Fig-




Figure 3: Cross-section of Ni-P/Ni-B-W dublex coating: a) as-plated,b) heat treated at 250 °C c) heat treated at 350 °C, d) heat treated at

Figure 4: Polarization curves in a 3.5 % NaCl aqueous medium ofas-plated and heat-treated Ni-P/Ni-B-W coatings: a) as-platedNiP/NiBW, b) heat treated at 300 °C, c) heat treated at 350 °C d) heattreated at 650 °C

Figure 5: Surface morphology of NiP/NiBW dublex coatings detectedby SEM after potentiodynamic measurement: a) as-plated, b) heattreated at 650 °C

ure 1). For heat-treatment temperatures up to 300 °C, thedublex coating preserved its amorphous structure.However, after heat treatment at and above 300 °C, thediffraction patterns showed the formation of Ni3B inter-metallic crystals. For the higher heat-treatment tempe-ratures up to 650 °C, formation of the nickel boridesprogressively increased. Drovosekov et al., reportedchemical bond formations between boron and tungstenin the Ni-B-W coating system. However, the majornickel borides formed during the heat treatments mighthave prevented the formation of the B-W bond.9,15 Inother words, the quantity of the boron in the coating washigh enough to prevent the formation of Ni-W com-pounds in the structure.16

SEM micrographs of the Ni-P/Ni-B-W coatings be-fore and after the heat treatments showed the formationof typical spherical nodular structures (Figure 2). Eachnodule appears to be formed by the unification of manygrains existing as colonies (Figure 2b), similar to thecase suggested by S. Ruan et al.17 Some microcrackswere noticeable on the surfaces of the as-platedNi-P/Ni-B-W samples. The microcracks may be due tothe internal stress caused by the relatively larger tungstenatoms in the coating structure.18,19

With the heat treatments, the structure progressivelycrystallized and, as consequence, a substantial reductionof the microcracks was noticed (Figure 2c and 2d). In aNi-B-W coating system, W atoms may selectively existat the boundaries of the nodules, from there, they maysegregates to the coating surface, during the heat treat-ments.16,17 This process may decrease the internal stressinside the coating, resulting in a substantial decrease ofthe microcracks on the coating surface.

The thickness of the Ni-P coating in the dublexcoating system was measured as 2 μm, while the averagethickness of the Ni-B-W (the other coating in thesystem) was measured as 11 μm (Figure 3). On the otherhand, it was obvious that the nodular structure seen in

the surface morphology of the Ni-B-W coating showedcolumnar growth starting from the Ni-P layer to thetopmost surface of the coating (Figure 3a). Furthermore,it was observed that adherence of the Ni-P coating to thesubstrate was good and there was no pore formationbetween the substrate and Ni-P coating. Pores seen in theinterface of Ni-P/Ni-B-W, in addition to pores partiallyobserved inside the Ni-B-W coating had a columnarstructure and they were considered to have been formeddue to the capturing of released hydrogen – even if insmall amounts – during the oxidation reaction of sodiumborohydride used as a the boron source.5 The poresdisappear with increasing heat-treatment temperatures.This may be a result of the diffusion of hydrogen atomsto the surface. They may promote better crystallizationof the coating and ease the formation of the Ni3B andNi2B phases (Figure 3b and 3c). After 650 °C heattreatment the major phase of the coating was noticed tobe Ni3B. At that stage adherence between the coatingsreached its best level, while the Ni-B-W coating showedcolumnar grains with a denser structure (Figure 3d).

As Figure 4, a difference of approximately 220 mVwas detected between corrosion potentials (Ecorr) ofas-plated and 650 °C heat-treated dublex coatings. Thisis the shifting of Ecorr values of the coatings towardnobler values with increased heat treatments applied tothe coatings. The anodic branch of the polarization curveof the coating before heat treatment showed the break-down potential at values around -310 mV (Figure 4a).But the current density increased at a constant rate,indicating that the unstable passive film formation on thecoating has disappeared rapidly. For heat treatment at300 °C, the breakdown potential was observed to shifttoward -220 mV. At 300 °C, which is the onset tem-perature of crystallization, corrosion potential shiftedtowards a positive end approximately 40 mV, comparedto the as-plated sample. At 350 °C, crystallization wasnearly completed and the corrosion potential had shiftedtowards more positive values. However, the breakdownpotential was observed (as with other samples) at around-180 mV. Nonetheless, it was detected that the currentdensity of this sample became higher as the potentialvalue increased compared with that for the to as-platedand heat-treated samples at 300 °C. For the heat treat-ment at 650 °C, a passive film formation on the coatingsurface was seen at around -190 mV, suggesting thatcorrosion rate was restrained at such potential range.However, as this protective film began to dissolve ataround -90 mV, a steep increase in the current densitywas observed.

The major reason for the difference between thecorrosion resistance of as-plated and heat-treatedNi-P/Ni-B-W coatings exposed to chloride ions wasundoubtedly associated with the transformation of themicrostructure from an amorphous to a crystalline mor-phology. The main reason for having a higher Ecorr valuethe heat-treated coating at 300 °C (where an amorphous




Figure 6: Polarization curves: a) steel substrate, b) Ni-B-W coatingheat treated at 650 °C, c) dublex Ni-P/Ni-B-W coating heat treated at650 °C

structure still prevailed) compared to the as-platedsample was the result of the borides formed during theonset of crystallization. The heat-treated sample at350 °C (where the microstructure had completely beentransformed to a crystalline structure) had a highercorrosion resistance compared to the sample heat-treatedat 300 °C.20 On the other hand, it is a known fact thatcorrosion resistance generally increases with addition oftungsten to a electroless nickel-boron coating system,because of the tendency to form an oxide film on thesurfaces.7,18 However, as seen in Figure 4, the corrosionresistance of the as-plated Ni-P/Ni-B-W sample having anodular structure did not increase, with the addition oftungsten. This is because the tungsten atoms were stuckin the colony boundaries, not to be segregated to thesurfaces during the corrosion process and therefore,could not be oxidized to promote the formation of amixed oxide film. However, depending on the increasedheat treatment temperatures segregation of W atomstoward surfaces at 650 °C was more likely to occur. Themixed oxide film a passive zone formed this way may bethe main reason for the substantial decrease of thecurrent density as observed here.

It can be seen that uniform corrosion occurred on thesurface of the as-plated sample in the amorphousstructure that has the lowest corrosion resistance (Fig-ure 5a). Conversely, on the surface of the heat-treatedsample at 650 °C complete crystallization were notedand the pits (indicated by arrows) in the grains within thecolonies were observed (Figure 5b).

To interpret the effect of the dublex coating oncorrosion resistance, the potentiodynamic polarizationmeasurements of the Ni-P/Ni-B-W and Ni-B-Wcoatings, as well as which were deposited under thesame process conditions and heat-treated at 650 °C, andcarbon steel substrate were studied (Table 3).

As can be observed from Figure 6, while the Ni-B-Wcoating and the dublex coating almost had the samecorrosion potential, more positive values at about 300mV, compared with that of the substrate. Among thecoating studied the dublex coating has the lowest corro-sion current density. The anodic branches of polarizationcurves of both the dublex and the Ni-B-W coatings havea passive zone, and both coatings had an Epit value ofapproximately -90 mV. Additionally, the current densityof the Ni-B-W coating at a constant rate increases,depending on the increased potential value. On the otherhand, the anodic branch of the dublex coating indicatedthat an entrance to a second passive zone at approxi-mately 20 mV. This passive zone may be related to theexistence of Ni-P in the dublex coating. A similar inter-pretation was reported by Zhang et al. for the corrosionof Ni-B-W surfaces.14 In general, corrosion starts at theoutermost surface of the substrate and proceed inward.However, the stable passive film formed on the Ni-Player on the substrate may act as a barrier for corrosionpropagation, causing the dublex coating to have better

corrosion resistance than the single-layer Ni-B-Wcoating.

5 CONCLUSIONS

The effect of heat treatments on the corrosion resis-tance of a Ni-P/Ni-B-W dublex coating deposited oncarbon steel was studied. The Ni-P/Ni-B-W coatingshave an amorphous structure for a heat treatments up to300 °C. The coatings start to crystallize at about 350 °Cand completed at about 650 °C with the major phasesbeing the nickel borides. The heat treatment, besidescausing nickel boride formation within Ni-B-W, alsocaused obtaining a denser Ni-P/Ni-B-W coating whenincreasing heat treatment temperature.

The corrosion resistance of the dublex coating in-creases substantially with increasing the heat treatmenttemperature. The dublex coating and the single-layerNi-B-W coating heat-treated at 650 °C indicated highercorrosion resistance as compared to that of steel sub-strate. When these two coatings were compared in termsof corrosion resistance, the dublex coating showed betterperformance.

6 REFERENCES

1 A. Brenner, G. Riddell, Nickel Plating on Steel by ChemicalReduction, J. Res. Nat. Bur. Std., 37 (1946), 31–35

2 J. Sudagar, J. Lian, W. Sha, Electroless nickel, alloy, composite andnano coatings-A critical review, J. Alloys Compd., 571(2013),183–204, doi:10.1016/j.jallcom.2013.03.107

3 Y. F. Shen, W.Y. Xue, Z.Y. Liu, L. Zuo, Nanoscratching Deformationand Fracture Toughness of Electroless Ni-P Coatings, Surf. Coat.Technol., 205 (2010), 632–640, doi:10.1016/j.surfcoat.2010.07.066

4 K. M. Gorbunova, M.V. Ivanov, V. P. Moissev, Electroless Depo-sition of Nickel-Boron Alloys – Mechanýsm of Process, Structure,and Some Propertýes of Deposits, J. Electrochem. Soc., 120 (1973),613–618, doi:10.1149/1.2403514

5 R. N. Duncan, T. L. Arney, Operatýon and Use of Sodium-Boro-hydride-Reduced Electroless Nickel, Plat. Surf. Finish., 71 (1984)12, 49–54

6 R. A. C. Santana, S. Prasad, A. R. N. Campos, F. O. Arau´ jo, G. P.DA Silva, P. Lýma-Neto, Electrodeposition and Mechanical Pro-perties of Ni–W–B Composites from Tartrate Bath, Prot Met PhysChem., 46 (2010) 1, 117–122, doi:10.1134/S207020511001017X

7 M. G. Hosseini, M. Abdolmaleki , H. Ebrahimzadeh, S. A. SeyedSadjadi, Effect of 2-Butyne-1, 4-Diol on the Nanostructure andCorrosion Resistance Properties of Electrodeposited Ni-W-BCoatings, Int. J. Electrochem. Sci., 6 (2011) 4, 1189–1205

8 T. Osaka, N. Takano, T. Kurokawa, T. Kaneko, K. Ueno, Characteri-zation of chemically-deposited NiB and NiWB thin films as acapping layer for ULSI application, Surf. Coat. Technol., 169–170(2003), 124–127, doi:10.1016/S0257-8972(03)00186-5

9 G. Graef, K. Anderson, J. Groza, A. Palazoglu, Phase evolution inelectrodeposited Ni-W-B alloy, Mater. Sci. Eng., B41 (1996),253–257, doi:10.1016/S0921-5107(96)01656-X

10 E. Lassner, W. D. Schubert, Tungsten: Properties, Chemistry, Tech-nology of the Element, Alloys, and Chemical Compounds, KluwerAcademic, New York, 1999

11 E. Beltowska-Lehman, Kinetics of Induced Electrodeposition ofAlloys Containing Mo from Citrate Solutions, Phys. Stat. Sol., 5(2008) 11, 3514–3520, doi:10.1002/pssc.200779404




12 A. I. Aydeniz, A. Göksenli, G. Dil, F. Muhaffel, C. Calli, B. Yüksel,Electroless Ni-B-W Coatings for Improving Hardness, Wear AndCorrosion Resistance, MTAEC9, 47 (2013) 6, 803–806

13 T. S. N. Sankara Narayanan, K. Krishnaveni, S. K. Seshadri, Elec-troless Ni–P/Ni–B Dublex Coatings: Preparation and Evaluation ofMicrohardness, Wear and Corrosion Resistance, Mater. Chem. Phys.,82 (2003), 771–779, doi:10.1016/S0254-0584(03)00390-0

14 W. X. Zhang, Z. H. Jiang, G. Y. Li, Q. Jiang, J. S. Lian, ElectrolessNiP/NiB Dublex Coatings For Improving The Hardness and TheCorrosion Resistance of AZ91 D Magnesium Alloy, Appl. Surf. Sci.,254 (2008), 4949–4955, doi:10.1016/j.apsusc.2008.01.144

15 A. B. Drovosekov, M.V. Ivanov, V. M. Krutskikh, E. N. Lubnin, Y.M. Polukarov, Chemically Deposited Ni-W-B Coatings: Composi-tion, Structure and Properties, Prot. Met., 41(2005) 1, 55–62,doi:10.1007/s11124-005-0008-1

16 F. Z. Yang, Z. H. Ma, L. Huang, S. K. Xu, S. M. Zhou, Electro-deposition and Properties of an Amorphous Ni-W-B Alloy beforeand after Heat Treatment, Chin. J. Chem., 24 (2006), 114–118,doi:10.1002/cjoc.200690004

17 S. Ruan, C. A. Schu, Mesoscale Structure and Segregation inElectrodeposited Nanocrystalline Alloys, Scripta Mater., 59 (2008)11, 1218–1221, doi:10.1016/j.scriptamat.2008.08.010

18 R. A.C. Santana, S. Prasad, A. R. N. Campos, F. O. Arau´ jo, G.P.Sýlva, P. Lima-Neto, Electrodeposition and Corrosion Behaviour of aNi–W–B Amorphous Alloy, J. Appl. Electrochem., 36 (2006),105–113, doi:10.1007/s10800-005-9046-2

19 R. A. Yildiz, A. Göksenli, B. Yüksel, F. Muhaffel, A. Aydeniz, Effectof Annealing Temperature on The Corrosion Resistance of Elec-troless Produced Ni-B-W Coatings, Adv Mat Res., 652 (2013),263–268, doi:10.4028/www.scientific.net/AMR.651.263

20 Z. Z. Hamid, H. B. Hassan, A. M. Attyia, Influence of DepositionTemperature and Heat Treatment on The Performance of ElectrolessNi–B Films, Surf. Coat. Technol., 205 (2010) 7, 2348–2354,doi:10.1016/j.surfcoat.2010.09.025




corrosion resistance of as-plated and heat …mit.imt.si/revija/izvodi/mit175/yuksel.pdf ·...

Documents