Treatments Mechanical Treatments Galvanic treatments Galvanic Hydraulics and Automotive Pre-Treatments Post-Treatments Period restorations Galvanic treatments Galvanic treatments : metal coating: formation methods Thegalvanic coatingis performed for decorative purposes, to resist corrosion and wear, and to resize worn or undersized pieces; the most commonly made are copper, nickel, chromium, zinc and gold, platinum and their alloys (bronzes, brass, tin-based alloys, etc.). In manygalvanic processes, for example in nickel plating, copper plating andsilverplating, the anode is made up of plates of the same metal as the coating that is applied: when the electric current passes, the metal of the anode progressively dissolves in the form of salt, thus replacing the one deposited on the cathode in the electrolytic bath. In other galvanic processes, the anode is instead formed by a material which, in the conditions in which the electrolysis is carried out, is not attacked, for example in the chrome plating where lead bars are usually used as anode. In this case the galvanic bath is gradually depleted in metal salt and this must be reintegrated from time to time by adding new quantities. Galvanic treatments: Metal coating: properties The properties of differentGalvanic coatings depend on their nature and also on that of the metal on which they are applied. Thus the common chromium plating has above all a decorative function, because the layers of chromium deposited are very thin, with thicknesses of the order of 0.005 mm, and always somewhat porous; moreover, their adhesion to iron is poor, so their application is always preceded by that of a more consistent nickel plating , which is essentially entrusted with the protection of the iron against atmospheric attack, on which the chrome adheres much better. The adhesion of the nickel plating on the iron, already good in itself, improves if the iron is previously subjected to a copper plating ; a chrome platingof excellent quality is therefore constituted by a copper plating , by a nickel plating and finally by the real chrome plating . Galvanic treatments: Metal coating: finishing operations Each galvanic deposit after being applied is subjected to cleaning with abrasive pastes, often necessary to ensure a good adhesion of the deposits subsequently applied: at the exit from the different galvanic baths the coatings show, in fact, a scarce and milky sheen due to the imperfect regularity of the metal layer. To avoid costly cleaning operations, small quantities of so-called brightening agents are introduced into many baths, generally consisting of organic compounds that directly cause the formation of shiny deposits, although almost always much more fragile. Rely on Pioli srl for your galvanic treatments Pioli srl, galvanic treatments in Reggio Emilia © 2016 Pioli Srl - Via C.Carrà 1/3/5/7 - 42124 Reggio Emilia - P.iva 01951310356 - Tel. 0522.94.13.39 - Rea n° RE-237645 - Cap.Soc. 10.000€ i.v. Privacy | Website by Clicom