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This work investigates the effect of multiwall carbon nanotubes (MWCNTs) on the mechanical and tribological behavior of a fiber reinforced composite (FRC). Fiber reinforced composites and nano-engineered FRCs are manufactured by resin transfer molding. In-plane tensile tests, in-plane shear tests and through-thickness compression tests are used to assess the influence of MWCNTs on the material mechanical behavior. Pin on disk dry sliding tests are used to quantify the effect of MWCNTs on the friction coefficient and the specific wear rate. It was determined that (1) MWCNTs have an influence on the improvement on both the through-thickness compression strength and the specific wear rate, and (2) they do not influence the material stiffness, in-plane tensile and shear strengths and the friction coefficient. It is assumed that the observed improvements are due to the demonstrated positive influence of the MWCNTs effect on the matrix/reinforcement interfacial strength and on the matrix fracture toughness.

WC/TiC-based cermets are, generally, considered as potential alloys widely used in hot rolling industry because of their interesting properties, namely high resistance to wear and oxidation. This work was aimed at studying the tribological behaviour, at relatively high temperatur, of WC/TiC-based cermets prepared using the powder metallurgy procedure. Three WC/TiC-Co cermets were prepared with different titanium carbide (TiC) additions namely 5%, 10% and 15% [in weight percentage (wt.%)], and a tungsten carbide-cobalt (WC-Co) grade without TiC which was considered as a reference material, resulting in a total of four samples. Friction tests were carried out, at two different contact temperatures of 450°C and 650°C, using a tribometer and an alumina ball during 2 h 46 min with load and speed of 20 N and 0.5 m/s, respectively. The obtained friction coefficients indicate that WC/TiC-based grades are relatively stable compared to the reference grade which shows an unstable friction coefficient with many peaks. It was also found that wear rates decreased with increasing TiC content, but exhibited a noticeable increase with rising temperature. Moreover, and in order to characterise the tribological degradation, the wear tracks microstructure composed of 80% WC, 15% Co and 5% of TiC, were analysed using a scanning electron microscope (SEM) process. Consequently, an enhancement of the wear resistance at 650°C was observed, and oxides of various types rich in tungsten, cobalt and oxygen were identified through SEM/energy electron spectrometery (EDS) images.