A. V. Isaev, V. V. Isaev, T. I. Devyatkina, E. G. Ivashkin, A. A. Bachaev
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引用次数: 0
Abstract
Free cyanide ions should be replaced by thiocyanate ions to decrease the toxicity of a cyanic silver-plating electrolyte. This allows the process to occur at high working current densities with the formation of a fine-grained deposit. This structure is shown to be formed due to the discharge of a mixed cyanide–thiocyanate complex. However, black or yellow spots causing article rejection form on the silver coating surface after washing and subsequent drying at elevated temperature. The spots are insoluble silver products, which further worsen the physicochemical characteristics of the coating. These spots can be removed by both chemical and electrochemical methods. The final elemental analysis of the coating composition after product removal shows no elements except for silver. The deposit structure has also been improved.
期刊介绍:
Russian Metallurgy (Metally) publishes results of original experimental and theoretical research in the form of reviews and regular articles devoted to topical problems of metallurgy, physical metallurgy, and treatment of ferrous, nonferrous, rare, and other metals and alloys, intermetallic compounds, and metallic composite materials. The journal focuses on physicochemical properties of metallurgical materials (ores, slags, matters, and melts of metals and alloys); physicochemical processes (thermodynamics and kinetics of pyrometallurgical, hydrometallurgical, electrochemical, and other processes); theoretical metallurgy; metal forming; thermoplastic and thermochemical treatment; computation and experimental determination of phase diagrams and thermokinetic diagrams; mechanisms and kinetics of phase transitions in metallic materials; relations between the chemical composition, phase and structural states of materials and their physicochemical and service properties; interaction between metallic materials and external media; and effects of radiation on these materials.