| Summary: | In this study, the potential of Fe<sub>3</sub>Al coating material as an environmentally friendly alternative to coatings containing critical elements for brake discs was investigated. A buffer layer of Cr–Mo steel (Ferro 55) that was about 500 µm thick was applied on a gray cast iron disc to enhance the coating quality and prevent the formation of hot cracks during solidification. The microstructural analysis of the cross-section of the coating showed that the buffer layer diffused into the Fe<sub>3</sub>Al coating, forming a combination of Fe<sub>3</sub>Al, Fe, and Fe<sub>3</sub>AlC<sub>0.5</sub> phases. The tribological properties of the Fe<sub>3</sub>Al-coated disc were evaluated using pin-on-disc tests against two different copper-free friction materials extracted from commercial brake pads. The wear results show a coefficient of friction comparable to that of an uncoated disc (≈0.55), but with a reduction in particulate matter (PM) emissions, which decreased from 600 to 476 #/cm<sup>3</sup>. The last issue is an interesting aspect that is gaining increasing importance in view of the upcoming international standards.
|
|---|