NANOTRIBOLOGY APPLICATION IN THE COINING INDUSTRY I - IMPLEMENT BASIC RESEARCH AND LAB TEST RESULTS ON PRODUCTION LINE
Enter briOn coining production presses in US Mint, a low viscosity stamping oil was sprayed on the blanks before they were fed between the obverse and reverse die. Although the fluid might reduce the friction between die and coin blank surface during coining to avoid micro adhesion, it penetrated into the surface defects, propagated micro cracks, and caused the micro-pitting on die surfaces. In the laboratory, according to the surface molecular thermodynamics model, a new technology of monomolecular Carboshield BTX film was developed. With this technology, a thin lubricant film was applied on the blank surfaces by burnishing process before stamping. The oil spray system was shut off. With this nano lubrication, die life was increased three times, and coin surface quality was improved, too.