New coatings for automotive fasteners

The obligation to reduce vehicle weights in order to decrease CO2 emissions leads to widespread use of light alloys. The Plus VLh topcoat improves performances linked to friction for difficult tightening cases, particularly for multi-tightening in aluminium and onto catophoretic paint. It is also effective in cases of loosening at high temperatures, while avoiding stick-slip problems when tightening. Thistopcoat can be applied in one coat onto the Geomet 321 grade A coating, which can be used for all fasteners and meets new expectations of the German automotive industry with whom an approval process has been initiated. Geokote topcoat is currently used in mass production forexternal car parts such as locks for doors and bonnets. It has been developed to meet requirements regarding resistance to chemicals and repetitive abrasion to the extent that it can now be applied to fasteners such as screws, nuts and clamping clips. This topcoat provides a thin layer optimal corrosion resistance and assembly properties which enable it to avoid the stick-slip effect, which can occur when tightening.