石墨对C/Cu复合材料微观组织及摩擦磨损性能的影响

利用机械合金化和放电等离子烧结技术制备C/Cu复合材料,用扫描电镜、透射电镜、X射线衍射仪、显微硬度计和销-盘摩擦磨损试验机对复合粉末和烧结体的组织结构、硬度、摩擦学行为进行了分析.结果表明:C/Cu复合粉末中Cu相粉末由纳米/亚微米复合颗粒组成,石墨主要以纳米层片状结构和非晶态存在,放电等离子体烧结体组织致密、细小且均匀,随着碳含量增加,烧结体的硬度与密度减小;C/Cu复合材料烧结样品在摩擦过程中形成润滑膜,表现出较低的摩擦系数和良好耐磨性,其磨损机制主要为氧化磨损、粘着磨损和剥层磨损.

Effect of graphite on structure, friction and wear characteristics of C/Cu composites

C/Cu composite was fabricated using mechanical alloying(MA) and spark plasma sintering technique.The structure,hardness,tribological properties and wear mechanism were examined using scanning electron microscopy,transmission electron microscopy,X-ray diffraction,microhardness and pin-on-disc testing.The results show that the Cu powder consists of nanometer and sub-micrometer particles and C powder exists in the form of nanometer layered structure and the amorphous in the milled composite powders.The compacts prepared by SPS reveal dense structure with fine particles uniformly distributed,and the hardness and density of the material decrease with increasing C content.The friction coefficient is low and wear resistance is improved for C/Cu composite compared with electrolytic coarse Cu compact,the dominant wear mechanism is oxidation wear,adhesive wear and delamination wear.