Formation and characterization of borohydride reduced electroless nickel deposits
TL;DR: In this article, the formation of electroless Ni-B deposits and evaluation of their characteristic properties were studied. And the corrosion resistance of Ni-b deposits, in 3.5% sodium chloride solution, both in as-plated and heat-treated (450°C/1 h) conditions, was also evaluated by potentiostatic polarization and electrochemical impedance studies.
About: This article is published in Journal of Alloys and Compounds.The article was published on 2004-02-25. It has received 136 citations till now. The article focuses on the topics: Electroless nickel & Nickel boride.
Citations
More filters
TL;DR: In this article, highly active Ni-B nanoparticles are used as a precursor for electroless nickel deposition and demonstrated their implementation as high-performance electric circuits on the CCPCB surface.
Abstract: Herein, we report novel and highly-active Ni–B nanoparticles as a precursor for electroless nickel deposition and demonstrate their implementation as high-performance electric circuits on the CCPCB surface
6 citations
TL;DR: In this paper, the solid-state decomposition of LiBH4 in the 2LiBH 4:CaNi5 system below the melting temperature of 270°C was reported.
6 citations
TL;DR: In this article, nanocrystalline electroless nickel-boron deposits (on steel substrates) were submitted to heat treatment under non-reactive atmosphere or to nitriding to enhance their properties.
Abstract: Nanocrystalline electroless nickel-boron deposits (on steel substrates) were submitted to heat treatment under non-reactive atmosphere or to nitriding to enhance their properties. Two different nitriding processes were used on the samples: one classical industrial process under an ammonia-based atmosphere and a novel, environment friendly treatment under a reduced pressure, nitrogen-based, atmosphere. The mechanical and tribological properties of the as-deposited and treated samples were investigated by various methods including nanoindentation and scratch tests. Their structural properties were also studied. The hardness of the deposits increased from 900 to 1250 hv100 due to optimal crystallization after the heat treatment and was further enhanced up to 1600 hv100 after nitriding. The scratch tests resistance of the coatings was good in both as-deposited conditions as well as after post treatment.
6 citations
01 Nov 2010
TL;DR: In this article, the effect of different surface finishes on the formation and growth of intermetallic reactions during soldering and thermal ageing with Sn-3Ag-0.5Cu and Sn-4Ag- 0.5cu solders are presented.
Abstract: The formation of intermetallic compounds (IMCs) on solder pads is strongly affected by the type of PCB surface finish since different finishes may lead to several different interfacial reactions and IMCs formation. Since the joint reliability is also determined by the type of the interfacial IMC layer between the solder and substrate, understanding how such intermetallic compounds form and grow during soldering and subsequent thermal ageing is essential. In this paper, experimental results of the effect of three different surface finishes namely: electroless nickel (phosphorus)/immersion gold, electroless nickel (boron)/ immersion gold and bare copper (for comparison) on the formation and growth of interfacial reactions during soldering and thermal ageing with Sn-3Ag-0.5Cu and Sn-4Ag-0.5Cu solders are presented. Several techniques of materials characterization including optical, image analysis, scanning electron microscopy and energy dispersive X-ray analysis were used to examine and quantify the intermetallics in terms of composition, thickness and morphology. The results showed that after soldering on Ni-Au finishes the reaction layer was found to consist of only one layer of (Cu, Ni) 6 Sn 5 with a needle-shape morphology. In addition, the results from SEM with energy dispersive x-ray (EDX) have revealed that isothermal aging at 150°C has caused the thickening and coarsening of IMCs as well as changing them into more spherical shape. During soldering on Ni(B)/Au finish it was observed that closer control of the reflow temperature was very important compared to soldering on Ni(P)/Au finish. Selective etching of solder joints also revealed that the morphology of the intermetallic formed is different across a single solder joint from the centre to the outside edge.
5 citations
01 Jan 2016
TL;DR: In this article, the composition and microstructures of binary and multicomponent alloy deposits were studied, and the effects of various agents and parameters such as metal salts, reductant, etc., on composition and structure in these alloy coatings were investigated in detail.
Abstract: Studying the composition and structure of EN coatings can be traced back to the 1950s, and such measurements for the EN films and other EP alloys have not been stopped till today. However, the systematical research was disappearance in the existing EP or relative books. Three parts of contents were studied in this chapter. The first part is the composition and microstructures of EP binary alloy deposits. The second part is the composition and microstructures of EP ternary and multicomponent alloy deposits. Effects of various agents and parameters such as metal salts, reductant, etc., on composition and structure in these alloy coatings were investigated in detail. The third part is the crystallization process and products, crystallization temperature, and activation energy of EP amorphous alloys.
4 citations
References
More filters
Book•
01 Jan 1990
TL;DR: The Electroless Plating: Fundamentals and Applications (ESPA) as discussed by the authors is a comprehensive text that covers both fundamental and applied aspects of electroless deposition, and was first introduced at SUR/FIN '91.
Abstract: Many texts have been written on surface finishing over the years that deal with electroless deposition as a sidelight. Through the talents and efforts of Glenn Mallory and Juan Hajdu, a comprehensive text, entitled Electroless Plating: Fundamentals and Applications, is available through AESF Headquarters. The editors have combined the efforts of 27 contributing authors to produce a wide-ranging text that covers both fundamental and applied aspects of the subject. Published by the AESF, the book was first introduced at SUR/FIN ‘91—Toronto.
963 citations
Patent•
23 Sep 1968
TL;DR: HIGH STABILITY, AUTOCATALYTIC ELECTROLESS NICKEL PLATING BATH COMPRISING an AQUEOUS SOLUTION CONTAINing about 0.08-016 MOLE/LITER NICKels IONS, about 019-0.38 MOLE / LITER HYPOPHOSPHITE IONS and ESSENTIALLY about 035-3.14 MOLE or Liter CITRATE IONS as discussed by the authors.
Abstract: HIGH STABILITY, AUTOCATALYTIC ELECTROLESS NICKEL PLATING BATH COMPRISING AN AQUEOUS SOLUTION CONTAINING ABOUT 0.08-016 MOLE/LITER NICKEL IONS, ABOUT 0.19-0.38 MOLE/ LITER HYPOPHOSPHITE IONS, AND ESSENTIALLY ABOUT 0.35-3.68 MOLE/LITER AMMONIUM IONS, ABOUT 0.0.-1.07 MOLE/LITER ACETATE ION AND ABOUT 0.007-0.14 MOLE/LITER CITRATE IONS, THE SOLUTION HAVING A PH IN THE RANGE OF ABOUT 7.0 TO ABOUT 9.5 THE AMMONIUM IONS COMPLEX PALLADOUS IONS INTRODUCED INTO THE PLATING BATH BY "DRAG OUT" FROM THE ACTIVATOR SOLUTION TO FORM A SOLUBLE AMMONIUM-PALLADIUM COMPLEX, WHICH INHIBITS REDUCTION OF PALLADOUS ION TO ZERO VALENT CATALYTIC PALLADIUM BY THE HYPOPHOSPHITE OF THE BATH. BY THE REMOVAL OF POTENTIAL CATALYST SITES FROM THE BATH OR BY RENDERING THE POTENTIAL SITES RELATIVELY CATALYTICALLY INACTIVE, RANDOM DEPOSITION OF THE NICKEL AND PREMATURE LOSS OF THE BATH IS AVOIDED.
154 citations
TL;DR: In this paper, the same fundamental reaction is occurring on all the coatings of the present study but over a different effective area in each case, which can be attributed to the decrease in the effective metallic area prone to corrosion.
Abstract: Electroless Ni-P composite coatings have gained a good deal of popularity and acceptance in recent years as they provide considerable improvement of desirable qualities such as hardness, wear, abrasion resistance, etc. The disagreement among researchers on the corrosion behaviour of these coatings warrants a thorough investigation. Among the various techniques available for the determination of corrosion resistance, electrochemical impedance spectroscopy (EIS) is considered to be superior as it provides not only an assessment of the corrosion resistance of different deposits but also enables the mechanistic pathway by which the deposits become corroded to be determined. The present investigation focuses on the evaluation of the corrosion resistance of electroless Ni-P and Ni-P-Si3N4, Ni-P-CeO2 and Ni-P-TiO2 composite coatings produced using an acidic hypophosphite-reduced electroless nickel bath, using EIS. The study makes evident that the same fundamental reaction is occurring on all the coatings of the present study but over a different effective area in each case. The charge transfer resistance of electroless Ni-P and Ni-P composite deposits are in the range 32,253–90,700 Ω cm2, whereas the capacitances of these coatings are in the range 11–17 µF/cm2. The improved corrosion resistance obtained for electroless Ni-P and Ni-P composite coatings is due to the enrichment of phosphorus on the electrode surface, which enables the preferential hydrolysis of phosphorus over that of nickel. The better corrosion resistance obtained for electroless Ni-P composite coatings can be ascribed to the decrease in the effective metallic area prone to corrosion. Among the three electroless Ni-P composite coatings, the corrosion resistance is in the following order: Ni-P-CeO2=Ni-P-Si3N4>Ni-P-TiO2.
119 citations
TL;DR: In this paper, the effect of phosphorus on the corrosion behavior of electroless nickel-plated mild steel in deaerated 40 w/o NaOH solution was examined using potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) techniques.
Abstract: Electroless Ni-P deposits with phosphorus content ranging from 4.8 to 12.8 weight percent (w/o) were examined using potentiodynamic polarization curves and electrochemical impedance spectroscopy (EIS) techniques to characterize the effect of phosphorus on the corrosion behavior of electroless nickel-plated mild steel in deaerated 40 w/o NaOH solution. Anodic polarization of the electroless Ni-P alloys in caustic NaOH solution shows that the passive current density decreases with increasing phosphorus content in the deposits. At an applied potential of -1.2 V vs. saturated calomel electrode (V SCE ) (close to their E corr ), EIS data indicate that the R ct for Ni-P alloys in NaOH solution increases with increasing phosphorus content. X-ray photoelectron spectroscopy (XPS) results suggest that the primary constituent formed on the Ni-P surface after EIS measurement in 40 w/o NaOH solution at an applied potential of -0.4 V SCE (in the passive region) is Ni(OH) 2 , which is responsible for the passivity of the Ni-P alloys. The polarization resistance of Ni-P alloys in NaOH solution at -0.4 V SCE also increases with increasing phosphorus content
111 citations