Silvering the earliest began in l800, a silver-plated patent is from Birmingham, England Elkington brothers in 1838, used in the bath for alkaline cyanide bath, and they invented the alkaline cyanide gold plating systemsimilar. More than a century, the basic formula of the silver plating solution and the formula is not very different, simply raising the silver coordination ion concentration in order to achieve fast-silvering. The main drawback of the the cyanide Department bath current density, this problem is resolved, efficient silver-plated current density can be as high as 10A/dm up to 1.5 ~ dm, Bright Silver, plated smooth and do not need to resort to light, can also be plated thick. In recent years, rapid development of electronic components, high-speed selective silver-plated, such as selective silver-plated lead frame, spray plating method. Current density as high as 300 ~ 3000A/dm, the concentration of potassium silver cyanide [KAg (CN) 2] in the bath up to 40 to 75g / L, the anode with platinum or platinum-plated titanium anode, so that in the 1s, can be plated with silver layer of about 4 ~ 5μm, it has been able to meet with aluminum bonding bonding between silicon and silver pad. Carbon disulfide brightener and can not get the full bright silver layer, and joined the bath to wait some time before taking effect, it is estimated that real brightener is generated by the CN reaction of carbon disulfide with the bath replaced by urea, thiourea sulfide, guanidine, cyanamide compounds (cyanamide) and other kinds of sulfides of certain compounds.
We use every day of the kettle inside the gall bladder is processed through silver plating. Due to poor thermal conductivity of the silver itself, silver-plated kettle has an insulating effect.
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