T.L. Rama Char

Electrodeposition of nickel-cadmium alloys from a pyrophosphate bath

Abstract Nickel has been codeposited with cadmium from a pyrophosphate bath. Detailed studies on alloy composition, cathode efficiency and cathode potential have led to a knowledge of the operating conditions necessary for obtaining satisfactory deposits containing 0–57% nickel. The cathode efficiency was 10–80%, and the limiting current density 8 A/dm 2 . X-Ray studies of the annealed deposits showed a close correspondence with the thermal diagram, with the presence of γ(b.c.c.), γ 1 (b.c.c.) and β (f.c.c.) phases and combinations at different compositions.

Electrodeposition of ternary alloys of iron--cobalt--cadmium from the sulphate bath

Abstract Ternary alloys of iron-cobalt-cadmium have been electrodeposited for the firdt time from the sulphate bath. Detailed studies on alloy composition, cathode efficiency and cathode potential have led to the operating conditions for obtaining satisfactory deposits containing iron 0–60, cobalt 0–60 and cadmium 7–100%. The cathode effeciency was 39–99%, and the limiting current density 30 A/dm2. X-Ray studies indicate the presence of mixtures of the b.c.c. and h.c.p. phases.

Inhibitors for Aluminium in Acid Solutions

Corrosion rates and inhibitor efficiencies have been determined for commercial aluminium in hydrochloric acid with the following inhibitors: nicotinic acid; dextrin; thiourea; and tannic acid. Polarisation studies have been made with thiourea and the mechanism of corrosion inhibition is herein discussed.