Cobalt, alloy with zinc

Rubidium metal alloys with the other alkali metals, the alkaline-earth metals, antimony, bismuth, gold, and mercury. Rubidium forms double halide salts with antimony, bismuth, cadmium, cobalt, copper, iron, lead, manganese, mercury, nickel, thorium, and zinc. These complexes are generally water insoluble and not hygroscopic. The soluble rubidium compounds are acetate, bromide, carbonate, chloride, chromate, fluoride, formate, hydroxide, iodide,... 

Zinc—Cobalt. Alloys of Zn—Co usually contain 0.3—0.8% cobalt. Higher cobalt alloys, from 4—8%, have shown better salt spray resistance (156), but the commonly plated alloy is 0.3—0.8%. One automotive company specifies 0.3—1.0%. Cobalt is expensive, and economics favor the lower alloys. Costs have been quoted for zinc—cobalt at 1.2 times the cost of chloride zinc, with zinc—nickel alloys at 1.5—1.6 times the chloride zinc. Deposits can be very bright, but the improved corrosion resistance advantage requires yellow or bronze chromates. Alkaline baths give fewer problems in plating components with lapped, spot-welded seams. 

Another prospective application of zinc oxide is the alloying with magnetic atoms like manganese, cobalt, or nickel to prepare diluted magnetic semiconducting alloys that are interesting as materials for spintronics, promising the possibility to use the spin of the electrons for electronic devices [176],... 

Materials such as metals, alloys, steels and plastics form the theme of the fourth chapter. The behavior and use of cast irons, low alloy carbon steels and their application in atmospheric corrosion, fresh waters, seawater and soils are presented. This is followed by a discussion of stainless steels, martensitic steels and duplex steels and their behavior in various media. Aluminum and its alloys and their corrosion behavior in acids, fresh water, seawater, outdoor atmospheres and soils, copper and its alloys and their corrosion resistance in various media, nickel and its alloys and their corrosion behavior in various industrial environments, titanium and its alloys and their performance in various chemical environments, cobalt alloys and their applications, corrosion behavior of lead and its alloys, magnesium and its alloys together with their corrosion behavior, zinc and its alloys, along with their corrosion behavior, zirconium, its alloys and their corrosion behavior, tin and tin plate with their applications in atmospheric corrosion are discussed. The final part of the chapter concerns refractories and ceramics and polymeric materials and their application in various corrosive media. 

Zinc Process [11.1,11.2,11.5,11.6]. In this process, cemented carbide scrap is treated in molten zinc or zinc vapor, which reacts with the binder to form intermetallic phases and a zinc-cobalt alloy. These reactions lead to a volume expansion of the binder and bloat the scrap. After vacuum distillation of zinc, the material is liiable and can be readily disintegrated. The condensed Zn can be re-used. The reclaimed carbide/metal sponge contains less than 50 ppm Zn. 

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. 

AMINOETHYLETHANDIAMINE (111-40-0) Combustible liquid (flash point 208°F/ 98°C oc). An organic base. Ignites spontaneously with cellulose nitrate, and possibly other nitrogen compounds. Silver, cobalt, or chromium compounds may cause explosions. Contact with nitromethane forms a heat-, friction-, and shock-sensitive explosive. Incompatible with acids, acrylates, aldehydes, alcohols, alkylene oxides, caprolactam solution, cresols, organic anhydrides, substituted allyls, epichlorohydrin, glycols, halogenated compounds, isocyanates, ketones, mercury, phenols, strong oxidizers, vinyl acetate. Attacks aluminum, copper, cobalt, lead, tin, zinc, and their alloys. 

Lustrous, hard metal hexagonal, cJose-packed structure. d 12.45. mp about 2450" bp about 4150", Sp heat (O ) 0,057 cal/g/°C. Does not react with acids, even aqua regia. Net oxidized by air in the cold on heating combines readily with oxygen the powdered metal forms the dioxide on ignit -mg in air. Supeficially attacked by coned alkaline hypochlorites, The powdered metal is attacked by chlorine above 200" by bromine between 300-700. Oxidized by fused alkali hydroxides. Forms alloys with platinum, palladium, cobalt, nickel, tungsten forms definite compds with zinc and with tin. 

In Raney s method a catalytically active metal is alloyed with a catalytically inactive one and then treated with a reagent that dissolves out the inactive metal. The catalytically inactive component that is to be dissolved out may be aluminum, silicon, magnesium, or zinc. The catalytically active metal is usually nickel, cobalt, copper, or iron. Noble-metal catalysts can, however, also be produced by Raney s method if an aluminum-platinum alloy (40% of platinum) or a zinc-palladium alloy (40% of palladium) is decomposed by hydrochloric acid.153... 

Nickel is a constituent of many metal alloys (e.g., Ni-Cr-Fe alloys for cooking utensils and corrosion-resistant equipment Ni-Cu alloys for food processing, chemical, and petroleum equipment, and for coinage Ni-Al alloys for magnets and aircraft parts Ni-Cr alloys for heating elements, gas-turbines, and jet-engines). Alloys of nickel with zinc, manganese, cobalt, titanium, and molybdenum are used for special industrial purposes, and alloys of nickel with precious metals are used for jewelry. 

Metallic impurities such as copper, nickel, iron, and cobalt cause corrosive reactions with the zinc in battery electrolyte and must be avoided particularly in zero mercury constructions. In addition, iron in the alloy makes zinc harder and less workable. Tin, arsenic, antimony, magnesium, etc., make the zinc brittle. ... 

Other alloy additions in commercial use include iron (often a two-layer electroplated coating with less iron—typically 20% —in the under-layer to assist formability and more iron—often 80% —in the outer layer to assist paintability) cobalt (0.15-0.35%) similar amounts of chromium (the zinc/ chromium/chromium-oxide coating known as Zincrox) and a range of ternary alloys and of composite coatings. 

In Fig. 1 there is indicated the division of the nine outer orbitals into these two classes. It is assumed that electrons occupying orbitals of the first class (weak interatomic interactions) in an atom tend to remain unpaired (Hund s rule of maximum multiplicity), and that electrons occupying orbitals of the second class pair with similar electrons of adjacent atoms. Let us call these orbitals atomic orbitals and bond orbitals, respectively. In copper all of the atomic orbitals are occupied by pairs. In nickel, with ou = 0.61, there are 0.61 unpaired electrons in atomic orbitals, and in cobalt 1.71. (The deviation from unity of the difference between the values for cobalt and nickel may be the result of experimental error in the cobalt value, which is uncertain because of the magnetic hardness of this element.) This indicates that the energy diagram of Fig. 1 does not change very much from metal to metal. Substantiation of this is provided by the values of cra for copper-nickel alloys,12 which decrease linearly with mole fraction of copper from mole fraction 0.6 of copper, and by the related values for zinc-nickel and other alloys.13 The value a a = 2.61 would accordingly be expected for iron, if there were 2.61 or more d orbitals in the atomic orbital class. We conclude from the observed value [Pg.347]

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