机械合金化法制备的Cu/SiC纳米复合材料的组织、热性能和力学性能评估

Nano-sized silicon carbide (SiC: 0wt%, 1wt%, 2wt%, 4wt%, and 8wt%) reinforced copper (Cu) matrix nanocomposites were manufactured, pressed, and sintered at 775 and 875°C in an argon atmosphere. X-ray diffraction (XRD) and scanning electron microscopy were performed to characterize the microstructural evolution. The density, thermal expansion, mechanical, and electrical properties were studied. XRD analyses showed that with increasing SiC content, the microstrain and dislocation density increased, while the crystal size decreased. The coefficient of thermal expansion (CTE) of the nanocomposites was less than that of the Cu matrix. The improvement in the CTE with increasing sintering temperature may be because of densification of the microstructure. Moreover, the mechanical properties of these nanocomposites showed noticeable enhancements with the addition of SiC and sintering temperatures, where the microhardness and apparent strengthening efficiency of nanocomposites containing 8wt% SiC and sintered at 875°C were 958.7 MPa and 1.07 vol%?1, respectively. The electrical conductivity of the sample slightly decreased with additional SiC and increased with sintering temperature. The prepared Cu/SiC nanocomposites possessed good electrical conductivity, high thermal stability, and excellent mechanical properties.

Evaluation of the microstructure,thermal and mechanical properties of Cu/SiC nanocomposites fabricated by mechanical alloying

Nano-sized silicon carbide (SiC: 0wt％, 1wt％, 2wt％, 4wt％, and 8wt％) reinforced copper (Cu) matrix nanocomposites were manu-factured, pressed, and sintered at 775 and 875℃ in an argon atmosphere. X-ray diffraction (XRD) and scanning electron microscopy were per-formed to characterize the microstructural evolution. The density, thermal expansion, mechanical, and electrical properties were studied. XRD analyses showed that with increasing SiC content, the microstrain and dislocation density increased, while the crystal size decreased. The coef-ficient of thermal expansion (CTE) of the nanocomposites was less than that of the Cu matrix. The improvement in the CTE with increasing sintering temperature may be because of densification of the microstructure. Moreover, the mechanical properties of these nanocomposites showed noticeable enhancements with the addition of SiC and sintering temperatures, where the microhardness and apparent strengthening ef-ficiency of nanocomposites containing 8wt％ SiC and sintered at 875℃ were 958.7 MPa and 1.07 vol％?1, respectively. The electrical conduct-ivity of the sample slightly decreased with additional SiC and increased with sintering temperature. The prepared Cu/SiC nanocomposites pos-sessed good electrical conductivity, high thermal stability, and excellent mechanical properties.