normalNickel‐Al2O3 alloys were electrodeposited from a Watt's‐type nickel‐electrolyte, which contained the second phase particles suspended in the solution. The effects of particle concentration, particle size, and plating conditions on microstructure and physical properties of the deposits were studied. Using submicroscopic Al2O3 particles, the room temperature yield strength increased from 8 kg/mm2 for pure nickel to 35 kg/mm2 for alloys containing 3.5–6.0 v/o (volume per cent) normalAl2O3 . It is believed that this increase was due to dispersion strengthening effects similar to those observed in sintered or internally oxidized metal‐metal oxide systems.

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Articles you may be interested inInfluence of milled α-Fe powders on structure and magnetic properties of Sm(Co,Zr)7/α-(Fe,Co) nanocomposite magnets made by mechanical alloying Structure and magnetic properties of electrodeposited, ferromagnetic, group 3-d element films grown onto GaAs (011) substrate J. Appl. Phys. 93, 7634 (2003); 10.1063/1.1543916 Structure and magnetic properties of electrodeposited cobalt nanowiresElectrodeposited films of cobalt-iron traditionally have been thought of in terms of their magnetic properties. The current investigation, however, has demonstrated that the mechanical properties of bulk coatings of cobalt-iron alloys can be equally attractive. Bulk coating (> 100 r-l) of cobalt-iron have been electrodeposited in the concentration range of l%-12.6% Fe as a function of cathodic current density (I-10 A/dm 2 ), electrolyte temperature (60-90°C) and ferrous concentration in the electrolyte (0.5-5.0 g/liter Fe++). Microstructure-mechanical property relationships, including yield strengths, ultimate tensile strengths and microhardnesses, have been determined for these materials after a 15 min, 482°C (900°F) stress relief anneal. Room temperature yield strengths as high as 102 kg/mm 2 (145 000 psi) and ultimate tensile strengths of up to 135 kg/mm 2 (192 000 psi) have been obtained. The general trends indicate that lower electrolyte temperatures, and higher iron contents yield coatings with greater strength.

A method has been developed which permits the use of an insoluble anode to electrodeposit cobalt by the addition of a sufficient amount of an electrochemically active substance such as vanadium pentoxide to the cobalt sulfate plating solution. In the absence of such additions, formation of Co3+ ions and cobalt oxide false(Co2O3false) at the platinum anode results during plating. The effects of the addition of vanadium pentoxide on the electrode process during plating have been investigated through the analyses of various electrolysis products as a function of additive concentration and plating time. The results show that besides cobalt deposition, vanadium ions of lower oxidation state (V++, V+++, VO++ ) are formed at the cathode and these ions seem to be responsible for the reduction and suppression of Co3+ ions and the oxide at the platinum anode. It has also been observed that the concentration of the added electrochemically active substance changed very little, indicating no incorporation of vanadium with the deposit during plating. The mechanical properties of the deposits prepared using an insoluble anode are compared with those obtained using a soluble anode.

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