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A new type of intelligent lubrication functional material, Cu-5Sn/22vol%Cr 3 C 2 /16vol%Ti 3 SiC 2 composite, was fabricated by powder metallurgy. The mechanical and tribological properties of Cu-Sn/Cr 3 C 2 /Ti 3 SiC 2 composite were studied. Ti 3 SiC 2 , as a lubricating component, had a better reinforcing effect than graphite. Compared with Cu-Sn/Cr 3 C 2 /Gr composite, Cu-Sn/Cr 3 C 2 /Ti 3 SiC 2 composite exhibited a 97% increase in hardness and 144% increase in compressive strength, reaching 223 HV and 821 MPa, respectively. Moreover, Cu-Sn/Cr 3 C 2 /Ti 3 SiC 2 composite's wear rate was lower than those of Cu-Sn/Cr 3 C 2 /Gr composite under different loads. The enhancement was ascribed to the Ti 3 SiC 2 particles, which had a well-bonded interface with the matrix and induced a higher Orowan strengthening effect. The studied composites with enhanced mechanical and tribological properties have promising potential for application in bearings and mechanical transmission devices. • Cu-Sn/Cr 3 C 2 /Ti 3 SiC 2 composite was fabricated by mechanical alloying and vacuum hot-pressing sintering. • The mechanical and tribological properties of composites were improved by replacing graphite with Ti 3 SiC 2. • The formed mechanically mixed layers enhanced the wear resistance of Cu-Sn/Cr 3 C 2 /Ti 3 SiC 2 composites. [ABSTRACT FROM AUTHOR]

Mo 2 C particle-reinforced Cu-1Cr and Cu-1Cr-0.19Zr (wt%) composites were fabricated by the powder metallurgy method. The effect of Mo 2 C particles on microstructure, mechanical properties, conductivity, softening resistance, and wear resistance of the composites was systematically studied. Dispersed Mo 2 C particles improved the properties and promoted the heterogeneous nucleation of Cr precipitates. The ultimate tensile strength, elongation, and conductivity of CuCrZr-5Mo 2 C (5 wt%) composite were 474.9 MPa, 33.7%, and 82.9% IACS, respectively. CuCr-5Mo 2 C and CuCrZr-5Mo 2 C composites exhibited high wear resistance and decreased friction coefficient. Cr precipitates and Mo 2 C particles promoted abrasive wear and reduced the wear rate. The dominant wear mechanisms of these composites were adhesion wear and abrasive wear. The average friction coefficient of CuCr-5Mo 2 C and CuCrZr-5Mo 2 C composites was 0.55 and 0.47, and the wear rate was 2.23 × 10−5 and 1.79 × 10−5 mm3·N−1·m−1, respectively. Mo 2 C particles effectively enhanced the high-temperature softening resistance by pinning grain boundaries. CuCr-5Mo 2 C and CuCrZr-5Mo 2 C composites' softening temperatures were 810 °C and 855 °C. These findings contribute to the development of high-performance copper composites. • CuCr-Mo 2 C and CuCrZr-Mo 2 C composites were fabricated by powder metallurgy. • The effect of Mo 2 C particles on microstructure and properties were investigated. • Mo 2 C particles promoted the heterogeneous nucleation of Cr precipitates. • Mo 2 C particles promoted abrasive wear and reduced the wear rate. • Mo 2 C particles enhanced the softening resistance by pinning grain boundaries. [ABSTRACT FROM AUTHOR]

Cr 3 C 2 and graphite (Gr) reinforced Cu-Sn matrix composites were fabricated by powder metallurgy. The effects of Cr 3 C 2 content (5, 10, 15, 20 wt%) on the microstructure, mechanical properties and tribological properties of studied composites were investigated. The results showed that Cr 3 C 2 particles were well bonded to the copper matrix. The as-sintered Cu-Sn/20Cr 3 C 2 /5Gr composite achieved a microhardness of 120 HV, an ultimate compressive strength of 330 MPa, and a yield strength of 206.49 MPa. Cr 3 C 2 particles improved the high-temperature stability of the composite with a softening temperature of 800 ℃. In addition, Cr 3 C 2 particles had an inhibitory effect on plastic deformation and adhesive contact during wear, improving the wear resistance of composites. The average friction coefficient and wear rate of Cu-Sn/20Cr 3 C 2 /5Gr were 0.32 and 2.48 × 10-5 mm3·N−1·m−1, respectively. It was worth noting that the dominant wear mechanisms of the studied composites changed with increased Cr 3 C 2 content, from adhesive wear to abrasive wear. This work was beneficial for developing copper matrix composites with high-temperature stability and enhanced wear resistance. [ABSTRACT FROM AUTHOR]

The tin bronze- x Cr 3 C 2 -graphite composites (x = 5, 10, 15, and 20 wt%) were fabricated by mechanical alloying and spark plasma sintering. Fine-scale uniform distribution of composites was achieved. The Cr 3 C 2 particles enhanced the mechanical properties and wear resistance of copper-based composites. The as-sintered tin bronze-20Cr 3 C 2 -graphite showed a hardness of 109 HV, a compressive strength of 333 MPa, and a yield strength of 219 MPa. In addition, the wear rate of as-sintered tin bronze-20Cr 3 C 2 -graphite was maintained in the order of 10−5 at 30 N, 50 N, and 70 N. The wear mechanism of the studied composites varied from surface fatigue and adhesion wear to abrasive wear with the increase of Cr 3 C 2 content during dry sliding. These findings provide a new method for developing copper-based composites with enhanced mechanical properties and wear resistance. • The tin bronze-Cr 3 C 2 -graphite composites were fabricated by powder metallurgy. • The Cr 3 C 2 particles enhanced the mechanical properties and wear resistance of copper-based composites. • The wear mechanism of the studied composites varied with the increase of Cr 3 C 2 content. [ABSTRACT FROM AUTHOR]