Phosphorus, Alloys

High performance sealants, 22 28 High phosphorus alloys, corrosion performance of, 9 710-711 High pinning Type II superconductors, 23 High pressure apparatus, 13 413 High pressure applications, 13 436-448 in commercial products, 13 436-438 in inorganic chemistry reactions, 13 440—448... 

Metal oxide sensors (MOS), smart, 22 717 Metal oxide supported catalysts, 5 336-337 coke formation on, 5 267—270 Metal passivation, in industrial water treatment, 26 137 Metal peroxides, 18 410 Metal phosphates, tertiary, 18 840 Metal-phosphorus alloys, 19 59 Metal phthalocyanines, electrochromic materials, 6 572t, 576-577 Metal prefinishing, detersive systems for, 8 413t... 

Electroless nickel—boron baths use sodium borohydride or dimethyl amine borane [74-94-2] in place of sodium hypophosphite (see Boron COMPOUNDS). The nickel—boron alloy is brittle, highly stressed, and much more expensive than nickel—phosphorus alloys. Nickel—boron is mainly used to replace gold in printed circuit board plating. 

Fig. 21.—Portion of Freezing-point Curve of Copper-Phosphorus Alloys.

P. Jolibois considers that only tin triphosphide and tritetritaphosphide are chemical individuals and that the other phosphides which have been reported are solid soln. or mixtures. A. C. Vivian found that when a mixture of phosphorus and tin is heated in sealed tubes, two conjugate soln. appear to be formed, and two definite layers of molten liquid are present. The maximum amount of phosphorus alloying with tin is 8 per cent., and the product melts at about 485° ... 

Fig. 28.—The Freezing-point Curves of Cobalt-Phosphorus Alloys.

In the nickel processes the reducing agent used most commonly is sodium hypophosphite, which gives a deposit comprising a nickel-phosphorus alloy rather than pure nickel the accelerators commonly are fluorides, and thiourea is a typical stabilizer. 

For further details of the iron-phosphorus alloys see this volume, Part III. 

To find the conditions in which the electroless deposition of gold at Ni-P surfaces with an acceptable appearance and adhesion would be possible, the activation of Ni-P substrates with 10% HC1 solution or a mixture of 0.1 M NH4F and sodium sulfamate was investigated. The results showed that only low phosphorus alloys (P content less than 5 wt%) pretreated with ammonium fluoride/sodium sulfamate mixture can be used for a successful electroless gold plating from cyanide solution and hydrazine as a reducing agent.31... 

Weber, T. A., and Stillinger, F. H., Interactions, local order, and atomic rearrangement kinetics in amorphous nickel-phosphorus alloys. Phys. Rev. B 32,5402 (1985). 

To counteract the (vexing) convection effects on kinetic experiments, Aogaki and co-workers, having developed a special electrode assembly to separate mass transport and kinetic effects, report a marked decrease in the exchange current density (about 25%) in magnetic fields imposed on a copper deposition cell. Virtually no effect on the transfer coefficient (a 0.44) was observed. Experimental results obtained in nickel-phosphorus alloy deposition, cupric ion reduction in ethylenediamine solutions, and the electrolytic reduction of acetophenone " are further demonstrations of the interaction of the magnetic fields with polarization characteristics, and point to the difficulty of fully eliminating the effect of convection and/or diffusion on electrode kinetics. 

The surface activation consisting of zinc deposition, heat treatment, and subsequent leaching of zinc (63, 64) was applied to different amorphous iron-, cobalt-, nickel-, and palladium-based alloys (63, 64). SEM measurements indicated the formation of a porous surface layer. Cyclic voltammetric examinations suggested an increase of surface area by about two orders of magnitude. Heat treatments at higher temperatures resulted in thicker, more porous surface layers and higher electrocatalytic activities (Table II). Palladium-phosphorus alloys with Ni, Pt, Ru, or Rh proved to be the best specimens. Pd-Ni-P with 5% Ni, after treatment at 573 K, exhibited even higher activity than that of the Pt-Pt electrode (Table II). These amorphous alloy electrodes were active in the oxidation of methanol, formaldehyde, and sodium formate. 

Ziewiec et al. [24] reported on the preparation, thermal stability and glass-forming ability of copper-nickel-phosphorus alloys. They found that, depending on the composition, melt spinning may result in either amorphous or partially crystalline systems, whose thermal behaviour was characterized by DSC, DTA, andXRD. 

Direct reduced iron, produced from the reduction of iron oxide, can react with air and moisture to produce hydrogen gas and heat. Ferrophosphorus is an iron and phosphorus alloy (18 to 25% phosphorus) used to adjust phosphorus concentration in steel. 

A. Durairajan, A. Krishnaiyer, B. Haran, R.E. White, B.N. Popov, Characterization of hydrogen permeation through a corrosion-resistant zinc-nickel-phosphorus alloy. Corrosion 56 (2000) 283—288. 

I99OB0I] Bolton, J.D., Jeandin, M., Jouanny Tresy, C., Mechanisms of Sintering in High Speed Steels with Phosphorus Alloying Additions , Powder Met., 33(2), 126-132 (1990) (Crys. Structure, Morphology, Experimental, 10)... 

Iron-Phosphorus Alloy (in Japanese), Shindo Gijutsu Kenkyu Kaishi, 30, 106-114 (1991) (Morphology, Experimental, Electr. Prop., Meehan. Prop., 10)... 

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