Chemical Polishing of Brass
BrassChem by POLIGRAT is a newly developed process for the chemical polishing and deburring of brass. The process combines high performance with low costs. It is also very environmentally friendly.
BrassChem is a two-phase immersion process. As regards both gloss and deburring it achieves a quality which was hitherto only achievable through electropolishing. The first stage of the treatment is to activate the surfaces, followed by a second phase consisting of the polishing proper. The entire moistened surface is treated evenly without the problems which arise during electropolishing with regard to shadowing, gas traces and contacting. The processing is carried out within a period of only a few minutes at room temperature (up to max. 35°C).
The activator and the polishing solution are supplied as concentrates and are prepared for use by the addition of water and hydrogen peroxide. A special patented stabilizer ensures that the amount of hydrogen peroxide used remains small. The concentration of the polishing solution lies in the range of 0.5% to2.0% concentrate with corresponding advantages as regards handling and cost-effectiveness. The polishing solution is free of nitric acid, sulphuric acid, fluoric acid, phosphoric acid and their salts. In use it is uniform in quality and speed up to a metal content of at least 40 g/l. No harmful vapours or annoying smells are produced during processing.
Due to the low concentration of the chemicals and the low viscosity of the solution, the consumption through drag-out is considerably lower than in the case of electropolishing, which works with highly concentrated, almost water-free electrolytes. Correspondingly low are the costs of making up the volume and the wastewater processing. When the rinse water has been neutralized with sodium hydroxide solution, the residue consists only of the metal hydroxides, whose purity is helpful as regards recycling, and no other metal salts.
BrassChem is supplied as a concentrate, separated into activator and polishing solution. It is prepared for use by the customer using water and hydrogen peroxide in accordance with the instructions. There are no additional requirements regarding the material of the tanks thus used, apart from the fact that they need to be resistant to hydrogen peroxide.