Tribological and Emission Behavior of Novel Friction Materials

Abstract

The tribological behavior and the related airborne particles emission of three copper-free automotive friction materials are investigated. The tests were conducted using a pin-on-disc tribometer equipped with a specifically designed clean-enclosure chamber for the emission measurement. Particle number concentration from particle size 0.3 µm up to 10 µm and the mass of emitted particles between 1 µm to 10 µm were measured. Particular emphasis was given to the chemical composition of the bulk materials, the friction layers and the emissions, in order to explain the acting wear mechanisms, and the recorded emission of airborne particles. The results indicate that the recorded emissions do not correlate with the friction coefficient and the wear rates, since the wear mechanisms exert a different influence on the tribological and emission behavior of the materials under study.

A novel path towards limiting non-exhaust particulate matter emissions of a commercial friction material through the addition of metallurgical slag

“…To understand the constituents of the secondary contact plateaus, point/object EDXS analysis was conducted on 8 different secondary plateau sites on multiple specimens for all compositions. Like other previous studies, the secondary contact plateaus were mainly made of Fe and O, symbolizing Fe oxides 32,33,35 . Apart from the Fe oxides, the secondary contact plateaus are made of minor elements like Si, Mg, Al, Mn, Sn, Cr, and Zn.…”

“…The OPS can measure the total particle number concentration in the size range from 0.3 μm to 10 μm, divided into 16 channels, and with a sampling frequency of 1 Hz. The OPS records and measures particle concentration up to 3000 particles/cm 3 , working with a self-controlled sampling flow rate of 1 l/min 32,33 .…”

A novel study on the reduction of non-exhaust particulate matter emissions through system vibration control

“…4 a, wherein, the limited extension of the secondary contact plateaus can be observed. Numerous studies 13 – 15 have shown that the predominant PM constituents are detached secondary plateaus. With the high removal of the secondary plateaus in the BC specimens, a naturally high emission magnitude of fine particles (Fig.…”

“…Wear particles, including the emitted airborne particles, are generally a result of the disruption of the secondary plateaus 10 – 14 . As far as the emission evaluation is concerned, by following a pre-defined protocol 13 , 15 , a ‘model scenario’ of PM emissions can be achieved through a pin on disc (PoD) tribometer, as it can be completely enclosed and its ‘environment’ can be easily controlled 3 .…”

Effect of the Addition of Waste Generated during the Plasma Cutting of Aluminum Products on the Friction and Emission Properties of a Commercial Friction Material Formulation

“…Following this, to remove any dust and impurities, the air is passed through a High-Efficiency Particulate Air (HEPA) filter (C), followed by the introduction of clean air inside the PoD chamber (D). The air velocity is maintained at 11.5 m/s and the air cleanliness at 1 #/cm 3 (the magnitudes were derived from previous studies [38,39]). A TSI ® Optical Particle Sizer Spectrometer (OPS, model 3330, TSI Incorporated, Shoreview, USA) was connected to D at the point F in Figure 1.…”