Alloy plating

The Fe, Co, and Ni deposits are extremely fine grained at high current density and pH. Electroless nickel, cobalt, and nickel—cobalt alloy plating from fluoroborate-containing baths yields a deposit of superior corrosion resistance, low stress, and excellent hardenabiUty (114). Lead is plated alone or ia combination with tin, iadium, and antimony (115). Sound iasulators are made as lead—plastic laminates by electrolyticaHy coating Pb from a fluoroborate bath to 0.5 mm on a copper-coated nylon or polypropylene film (116) (see Insulation, acoustic). Steel plates can be simultaneously electrocoated with lead and poly(tetrafluoroethylene) (117). Solder is plated ia solutioas containing Pb(Bp4)2 and Sn(Bp4)2 thus the lustrous solder-plated object is coated with a Pb—Sn alloy (118). 

Hard plating is noted for its excellent hardness, wear resistance, and low coefficient of friction. Decorative plating retains its brilliance because air exposure immediately forms a thin, invisible protective oxide film. The chromium is not appHed directiy to the surface of the base metal but rather over a nickel (see Nickel and nickel alloys) plate, which in turn is laid over a copper (qv) plate. Because the chromium plate is not free of cracks, pores, and similar imperfections, the intermediate nickel layer must provide the basic protection. Indeed, optimum performance is obtained when a controlled but high density (40—80 microcrack intersections per linear millimeter) of microcracks is achieved in the chromium lea ding to reduced local galvanic current density at the imperfections and increased cathode polarization. A duplex nickel layer containing small amounts of sulfur is generally used. In addition to... 

Two pieces of work-hardened 5000 series aluminium alloy plate were butt welded together by arc welding. After the weld had cooled to room temperature, a series of hardness measurements was made on the surface of the fabrication. Sketch the variation in hardness as the position of the hardness indenter passes across the weld from one plate to the other. Account for the form of the hardness profile, and indicate its practical consequences. 

To avoid decarburization and Assuring of the carbon and low-alloy steels, which is cumulative with time and, for all practical purposes irreversible, the limitations of the Nelson Curves should be followed religiously, as a minimum. Suitable low-alloy plate materials include ASTM-A204-A, B, and C and A387-A, B, C, D, and E, and similarly alloyed materials for pipe, tubes, and castings, depending upon stream temperatures and hydrogen partial pressures, as indicated by the Nelson Curves. 

Pinner, R., Copper and Copper Alloy Plating, Copper Development Assoc., London (1962)... 

Lee, W. G. (1971) Improvement of solder connections by gold alloy plating. Plating, 58, 997-1001. 

Several binary alloys of technological importance are known to form by way of an underpotential co-deposition mechanism. The abnormal composition-potential relationship observed in Cu-Zn alloys deposited from cyanide-based electrolytes, one of the most widely used commercial alloy plating processes, is attributed to the underpotential co-deposition of Zn [64]. The UPD of Zn is also known to occur on Co and Fe and has been included in treatments focusing on the anomalous co-deposition of Co-Zn [65] and Ni-Zn alloys [66-68]. Alloys of Cu-Cd have been shown to incorporate Cd at underpotentials when deposited from ethylene diamine solution [69-71]. 

Iron(II) formate dihydrate, 14 537 Iron(II) fumarate, 14 537 Iron gelbs, 19 399, 400 Irondl) gluconate dihydrate, 14 541 Iron group carbides, 4 690-692 Iron halides, 14 537-540 Iron hydroxide, water exchange rates and activation parameters of hexaaqua complexes, 7 589t Iron(II) hydroxide, 14 542 Iron(III) hydroxide, 14 542 Iron hydroxides, 14 541—542 Iron(II) iodide, 14 540 Iron(III) iodide, 14 540 Iron/iron alloy plating, 9 813—814. See also Fe entries... 

Lead/lead alloy plating, 9 814-817 Lead-lead frame alloys, properties of, 17 842t... 

Nickel(II), concentration formation constant of chelates, 5 717t Nickel 200, in galvanic series, 7 805t Nickel acetate tetrahydrate, 17 117 Nickel acetylacetonate, 17 117 Nickel alloying process, 17 99-100 Nickel alloy plating, 9 821-822 Nickel alloys, 17 88, 95-104 13 512, 515-525... 

Zinc-iron alloy plating, 9 831 Zinc iron chromite brown spinel formula and DCMA number, 7 348t Zinc Iron Chromite Brown pigment for plastics, 7 369t Zincite... 

Zinc-nickel alloy plating, 9 829-831 Zinc Omadine... 

U.S. imports for consumption, 6 545t Zinc/zinc alloy plating, 9 827-832 Zineb, 7 591... 

B 96 Copper-Silicon Alloy Plate, Sheet, Strip, and Rolled Bar for General Purposes and... 

The use of Zn-Cr(III) alloy plating has almost replaced the use of Cr(VI) in the electroplating industry due to its excellent corrosion resistance and its lower toxicity. Recently, a solvent extraction procedure for separating and selectively recovering the two metals, zinc and chromium, from electroplating wastewaters has been demonstrated [10]. 

The earlier papers on zinc alloys plating were described by Brodd and Leger [92]. 

After fixing Pd catalyst on modified nylon 12 surfaces by various methods, they were coated by electroless Ni-P alloy plating. Alumina- or silica-modified nylon 12 was well wet by electroless plating liquid, and modified nylon 12 situations in a liquid were good dispersed. Nickel metal was deposited on silica or alumina surface. Finally, it was confirmed that the formation of metal layer was depended mainly on the method of Pd catalyst fixing. 

Secondary cells are voltaic cells that can be recharged repeatedly. The lead storage battery and nickel-cadmium cell are examples of secondary cells. The lead storage battery consists of six voltaic cells. Its electrodes are lead alloy plates, which take the form of a grill, filled with spongy lead metal. The cathode consists of another group of plates filled with lead (IV) oxide, P6O2. Dilute sulfuric acid is the electrolyte of the cell. When the battery delivers a current, the lead is oxidized to lead ions, which combine with sulfate fS0 7 ions of the electrolyte to cover the lead electrode. 

Permeation experiments (Fig. 14-2 b) conducted with hydrogen as the interstitial component i diffusing across a (Pd,Pt) alloy plate are in agreement with the above conclusions [B. Baranowski (1989)]. 

Typical bath constituents for alloy plating are given in Table 3, which also gives some impression of the variety of alloys which may be electrodeposited. 

The use of mixed complex baths is interesting since the concentration of one free metal ion may be altered by varying the amount of one ligand. Thus, in a copper—tin bath, cyanide content may be varied to alter the activity of copper ions, with little or no effect on tin which is present as stannate or as a pyrophosphate complex. It is evident that some knowledge of the coordination chemistry will reduce the degree of empiricism in developing alloy plating baths. 

Zinc Alloys. There has been considerable worldwide activity in the area of plating zinc alloys. This interest results from efforts to improve the corrosion resistance of automobiles and automotive components without using cadmium (150). The use of zinc—alloy plated coil for automotive body steel originated in Japan, has spread through Europe, and more recendy has come to the United States. Three zinc alloys dominate the interest zinc—nickel, zinc—iron, and zinc—cobalt. Europe produces predominantly zinc—nickel. In Japan, zinc—nickel and zinc—iron are more popular (151). The annual worldwide nickel consumption for zinc—nickel alloy plating has been estimated at 2700—3175 metric tons (152). In the United States, consumption is estimated at about 225 metric tons for this purpose. Alloys are generally 6—12% nickel. Usage is expected to increase. 

During service inspection corrosion of an upper surface wing panel containing an access door was observed. The panel and door were made from an alloy plate to which aluminum catches were attached for securing the door in the closed position. Stainless shims were fitted between the catches and the aluminum plate. 

Tin Alloys, plating, making flat glass Bolivia, Brazil, Malaysia 81... 

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