A comparative analysis of ladle furnace slag and electric arc furnace slag as abrasives in a friction material formulation: friction and particulate emission behaviour

In this study, three friction materials were analyzed to evaluate the tribological behavior of novel, sustainable abrasives derived from steelmaking slags. A reference formulation containing alumina was compared with two alternative formulations incorporating Electric Arc Furnace (EAF) and Ladle Furnace (LF) slags. Tribological tests assessed friction stability, wear, and particulate emissions, while detailed characterization of worn surfaces and cross-sections provided insight into wear mechanisms. All materials formed secondary plateaus mainly composed of compacted iron oxides, as common in systems employing cast iron disc counterfaces. While all abrasives contributed to the generation of Fe-rich wear debris, EAF slag particles showed superior performance due to their ability to fragment and integrate into the friction layer, enhancing its compactness and reducing wear and emissions. LF slag particles, in contrast, did not fragment and failed to bond effectively with the friction layer. The results highlight the potential of EAF slag as an effective, eco-friendly abrasive in brake pads. Further validation under realistic conditions is recommended through inertia dynamometer testing.