三维双连续铜/石墨自润滑复合材料的构筑及其摩擦磨损性能研究

以聚氨酯海绵为三维连续网络结构模板，采用浸渍法在聚氨酯海绵骨架表面均匀涂敷石墨浆料构筑具有三维连续网络结构的石墨骨架，然后在石墨骨架中填充铜合金粉，经排胶-热压烧结工艺制备石墨相和金属铜呈三维双连续复合型结构的铜/石墨自润滑复合材料. 研究考察了三维双连续复合结构对材料承载能力和抗冲击破坏能力的影响，并探究了材料在重载作用下的摩擦磨损行为. 结果表明：通过三维双连续结构设计，能够有效改变石墨相的富集状态和分布形式，并借助连续金属铜基体的高承载作用，显著提升材料在重载作用下的减摩抗磨性能. 在180 N载荷下与轴承钢相对摩擦时，块体663铜合金和均相铜/石墨复合材料均出现急剧磨损并与摩擦配副发生“卡咬”现象，其中块体663铜合金与配副由于“卡咬”严重而停止试验，均相铜/石墨复合材料的磨痕深度达1.38 mm. 然而，具有三维双连续结构的铜/石墨复合材料的摩擦系数可保持约在0.12左右，磨痕深度为0.16 mm，展现出优异的长时间耐磨损性能，磨损率约为5.3×10−6 mm3/(N∙m). 同时，该结构设计能够大幅减少石墨相与金属铜间的弱界面数量，并有效利用连续石墨相对裂纹传播路径的“歧化”引导和金属铜对扩展裂纹的钝化作用，使复合材料在保持铜合金高承载的同时显著提升材料的抗冲击破坏能力. 具有三维双连续结构的铜/石墨复合材料的抗弯强度可与块体663铜合金比拟，高达372±38 MPa，是均相铜/石墨复合材料抗弯强度的2.0倍左右. 此外，具有三维双连续结构的铜/石墨复合材料还具有更加优异的抗外载冲击破坏能力，其冲击韧性高达32.8±3.1 J/cm2，比均相铜/石墨复合材料的冲击韧性提高了11.1倍，甚至比块体663铜合金的冲击韧性高出2.2倍.

Using polyurethane sponge as a template for three-dimensional (3D) continuous network structures, a 3D continuous network graphite skeleton was constructed by uniformly coating graphite slurry on the surface of the polyurethane sponge skeleton via impregnation method. Then, copper alloy powder was filled into the graphite skeleton, and a copper/graphite self-lubricating composite material with a 3D double-continuous hybrid structure composed of graphite phase and metallic copper was prepared through debinding and hot-pressing sintering processes. This study investigated the effects of the 3D double-continuous composite structure on the load-bearing capacity and impact resistance of the material, and explored the friction and wear behavior of the material under heavy loads. The results show that: through the 3D double-continuous structure design, the enrichment state and distribution form of the graphite phase can be effectively altered, and with the high load-bearing effect of the continuous metallic copper matrix, the friction-reducing and wear-resistant performance of the material under heavy loads is significantly improved. When sliding against bearing steel under a load of 180 N, both the bulk 663 copper alloy and the homogeneous copper/graphite composite exhibited severe wear and underwent seizure with their friction pairs. The test of the bulk 663 copper alloy was stopped due to severe seizure, while the wear scar depth of the homogeneous copper/graphite composite reached 1.38 mm. However, the copper/graphite composite with the 3D double-continuous structure maintained a coefficient of friction (COF) of approximately 0.12, with a wear scar depth of 0.16 mm, demonstrating excellent long-term wear resistance, with a wear rate of about 5.3×10^-6 mm3/(N·m). Meanwhile, this structural design can greatly reduce the number of weak interfaces between the graphite phase and metallic copper, and effectively utilize the "diversion" guidance of the continuous graphite phase on crack propagation paths and the passivation effect of metallic copper on propagating cracks, enabling the composite material to maintain the high load-bearing capacity of copper alloys while significantly improving its impact resistance. The flexural strength of the copper/graphite composite with the 3D double-continuous structure is comparable to that of the bulk 663 copper alloy, reaching up to 372±38 MPa, which is about 2.0 times the flexural strength of the homogeneous copper/graphite composite. In addition, the copper/graphite composite with the 3D double-continuous structure exhibits more excellent resistance to external load impact failure, with an impact toughness of up to 32.8±3.1 J/cm2, which is 11.1 times higher than that of the homogeneous copper/graphite composite, and even 2.2 times higher than that of the bulk 663 copper alloy.

搜集汇总

背景与挑战

背景概述

该数据集聚焦于三维双连续铜/石墨自润滑复合材料的制备与性能研究，通过聚氨酯海绵模板和热压烧结工艺成功构筑了石墨相和金属铜呈双连续结构的复合材料。研究证实，这种结构设计显著提升了材料在重载下的减摩抗磨性能（如摩擦系数约0.12）和抗冲击能力（冲击韧性达32.8±3.1 J/cm²），同时增强了承载强度，为解决重载条件下的摩擦磨损问题提供了有效方案。