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Copper matrix composites reinforced with different mass fractions of TiC particles were prepared by spark plasma sintering （SPS） technology. The microstructures of the copper matrix composites with different sintering temperatures and TiC contents were investigated. The effects of TiC content on the electrical conductivity， nano-mechanical properties， microhardness， tensile properties， and tribological behaviors of the composites were studied. Results show that the TiC/Cu composites obtained by sintering at 850 ℃ have a dense structure， with a good bonding between the reinforcements and the matrix. On the one hand， as the TiC content increases， the grains of the copper matrix phase in the TiC/Cu composites are continuously refined and the grain boundary density increases. This leads to an increase in the hardness and yield strength of the composites. On the other hand， the increase in TiC content gradually leads to the development of pores and cracks at the bonding interface between the reinforcement and matrix. When bearing or transmitting load， the pores and cracks will become the preferred location for stress concentration and crack formation， resulting in a reduction in the conductivity， tensile strength， and elongation of the composite. With TiC content of 5%-15%（mass fraction，the same below）， the composites have higher tensile strength， modulus of elasticity and yield strength， appropriate hardness， and better overall mechanical properties. When the TiC content exceeds 20%， the yield strength of TiC/Cu composites decreases significantly and the composite fracture mechanism changes from ductile fracture to brittle fracture. The TiC reinforcements significantly improve the tribological properties of the copper matrix composites. The friction coefficient and wear of the composites during friction increase linearly with increasing load and tend to decrease with increasing TiC content. At a TiC content of 20%， the composite has the highest wear resistance and lowest coefficient of friction. The wear mechanism is dominated by abrasive wear， accompanied by slight adhesive wear and oxidative wear.

Titanium (Ti) materials are highly valued in the medical field for their outstanding biocompatibility and corrosion resistance. However, challenges such as suboptimal wettability and wear resistance can impact the tribological properties of titanium implants, potentially leading to implant failure. This study explores the application of ultrafast pulsed laser processing to create two distinct structures, circular pits and grooves, on the surface of titanium materials. The samples underwent low-surface-energy treatment, after which the wettability and wear resistance of the textured surfaces were evaluated. The findings indicate that the textured surfaces exhibit improved hydrophobic properties and reduced surface wear. Specifically, the textured surfaces demonstrated a remarkable 73.68% reduction in wear compared to the untextured surfaces. These results underscore the potential of etching textured structures onto titanium surfaces to enhance their wear resistance, thereby offering promising implications for the improvement of titanium implant performance. [ABSTRACT FROM AUTHOR]

The tribological performance of internal combustion engines (ICEs) has an important impact on fuel efficiency and power consumption, and the wear of cylinder liner-piston ring (CLPR) system affects the operation reliability. The surface texture of CLPR can significantly improve the tribological performance of ICEs. Aiming at the friction and wear of CLPR, the different textures (dimple, equilateral triangle and square) are generated on the CLPR using laser processing, and the different tests are conducted on the UMT-TriboLab tester. The coefficient of friction, wear topography, surface roughness parameters and profiles are measured. The results show that, compared with the non-textured surface, the dimple texture surface of piston ring or cylinder liner has better tribological performance. If the textures coexist on the cylinder liner and piston ring, the tribological performances are better than single surface texture. Furthermore, the mixed textures can significantly improve the surface lubrication performance and the ability to store abrasive particles, and better surface quality can be obtained at the same operating conditions to enhance the tribological performance. This study can provide guidance for reducing the friction and wear of CLPR system of ICEs, and achieve energy saving and emission reduction of ICEs. [ABSTRACT FROM AUTHOR]