Matrix replacement is the most important change in a composite and requires extensive testing of the material properties of alternative matrices prior to replacement. In our case, the matrix currently used in the manufacture of composite brake pads is no longer in use. The objective of this master's thesis is to find a suitable alternative matrix and evaluate the effects of replacement in terms of frictional properties, wear and temperature resistance. Four sample matrices of novolak phenol-formaldehyde resin were compared, which differ from flowability and additives. The samples of the composite friction material were tested for their frictional properties on a Krauss machine according to the reference composite friction material. Wear mechanisms were identified using light microscopy and analysis SEM and temperature resistance was compared using DSC analysis. The results of the friction tests showed better frictional properties of the composites with the medium-flow phenol-formaldehyde resin (µ = 0.49) compared to the reference composite (µ = 0.46). The DSC analysis results showed the highest temperature resistance of the medium-flow phenol-formaldehyde resin (T = 470 °C) compared to the reference resin (T = 450 °C). The shear strength results did not differ significantly. The lowest volume loss was measured on the medium-flow resin (168 mm3) compared to the reference material (193 mm3). SEM figures show the highest wear for the composite with short-flow resin with NBR elastomer additives. The wear mechanism is predominantly abrasive in the form of grooves, pitting, and in the form of delamination and areas of matrix tear-outs due to oxidation and fatigue. The most suitable alternative phenol-formaldehyde resin was a novolak-phenol-formaldehyde resin with medium flowability, which would be interesting for the production of a composite friction material.
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