- Mar 24, 2018 -
The chrome plated basin waste process has many common features in addition to other plating species:
①The main component of the chromium plated basin waste electrolyte is not the metal chromium salt but the chromic acid with strong oxidizing property.
②The current efficiency is very low, generally 13% to 16%, and the maximum is only about 23%. Therefore, a large amount of hydrogen is precipitated during the chrome plated basin waste process, and a toxic mist is emitted. A good suction device and a chrome mist inhibitor are needed.
③The solution must add a small amount of additional anions, such as SO42-, F-, SiF62-, etc., but also to maintain a certain amount of trivalent chromium in the electrolyte.
④The dispersion ability is low. For parts with relatively complex shapes, pictographic anodes, protective cathodes, etc. must be used in order to obtain a good coating.
⑤The current density used is very high, sometimes several times higher than the current density of the plating species. The chrome plated basin waste process also has a higher cell voltage and often requires more than 12 volts, while other plating types use a 6 volt power supply.
⑥The control of temperature and current density is demanding, and there must be close cooperation between the two. Current density is fixed, the temperature can only change 1 ~ 2 °C, the temperature is fixed, the current density changes 2 ~ 3A/dm2.
⑦The anode used for chrome plating is not metallic chromium, but insoluble anodes such as lead, lead-tin or lead-antimony.
⑧Because the chromium layer is easily passivated, it is not allowed to cut the power midway during the plating basin waste process.
The above points reflect some of the characteristics of chrome plated basin waste production, that is, its particularity. This particularity constitutes the special nature of the chrome plated basin waste process that distinguishes it from other electroplating processes. However, chrome plating is a kind of electroplating plating, and it certainly has the general rule of electroplating. We should start from the production practice, gradually study and understand the entire process of chrome plating, understand and master the special and universal rules of the chrome plated basin waste process, make it Better service for production.