Role of Attapulgite on Altering the Performance Properties of Cu-Free Brake-Pads
Abstract: Attapulgite, a unique clay mineral is a crystalloid hydrous magnesium-aluminium silicate, composed of silicon oxide, aluminium oxide, magnesium oxide, iron oxide etc. having formula Mg5Si8O20(HO)2(OH2)4•4H2O. Its structure is somewhat between laminated and chain structure having very high surface area and porosity. Its magnesium silicate structure resembles a brick wall with every second brick missing. This leaves elongated porous channels that are highly absorbent. Its fibers were proven to be excellent substitute for asbestos in brake-pads. Hardly anything in details is reported on its exact role in controlling tribo-properties of friction materials (FMs) especially Cu-free FMs. Hence, in this work a series of brake-pads with five types was formulated and developed with increasing amount of attapulgite (0, 5, 10 and 15 wt. %) by compensating with inert barite particles in Cu-free FMs.