Page 75 - 摩擦学学报2025年第10期

1472 摩擦学学报（中英文） 第 45 卷

dimensional skeleton-reinforced Cu/PTFE composites were respectively prepared by the vacuum hot-pressing and
sintering method. And the microstructure, mechanical properties, thermal conductivity and tribology properties of these
three materials were investigated by using the Scanning electron microscope (SEM), X-ray diffraction (XRD), DR-III
thermal conductivity tester, and UMT friction wear tester. The results showed that the copper particles in the particle
reinforced Cu/PTFE composites were uniformly distributed in the PTFE matrix, and the skeleton Cu in the three-
dimensional skeleton reinforced Cu/PTFE composites was tightly bonded with the PTFE matrix through interlocking
mode. The three-dimensional skeleton reinforced Cu/PTFE composites compared to particle-reinforced Cu/PTFE
composites, the three-dimensional skeleton reinforced Cu/PTFE composites were better crystallized in the composites
during composites preparation due to the homogeneous thermal conductivity of the skeleton Cu, then its matrix hardness
was slightly improved. The load-bearing and thermal conductivity of PTFE matrix composites were effectively enhanced
by the addition of copper metal phase. For particle reinforced Cu/PTFE composites, the copper particles dispersed in the
PTFE matrix and formed a structural discontinuity, so it improved the thermal performance at certain limitations, But,
the three-dimensional skeleton reinforced Cu/PTFE composites could form a continuous thermal conductivity channel
and can effectively dispersing the load, resulting in the thermal conductivity and load-bearing capacity of three-
dimensional skeleton reinforced Cu/PTFE composites is significantly good than that of the particle reinforced Cu/PTFE
composites. Friction and wear results showed the friction coefficient of three-dimensional skeleton reinforced Cu/PTFE
composites was slightly higher than that of PTFE and particle reinforced Cu/PTFE composites. And, the particle-
reinforced Cu/PTFE composites showed a small upward trend of the friction coefficient, which may have been attributed
to the hard copper particles in the composite was gradual exposure out and resulting in the fluctuations of the friction
coefficient. By comparing with the PTFE materials, the addition of copper metal phase significantly improved the wear
resistance of PTFE-based composites. The plastic deformation in the matrix of the particle-enhanced Cu/PTFE
composites and the three-dimensional skeleton reinforced Cu/PTFE composites was gradually reduced. In addition, the
void structure of the copper foam skeleton has the accumulation of wear debris which could promoted the formation of
the transfer film. So, the wear resistance of particle-reinforced Cu/PTFE composites and three-dimensional skeleton-
reinforced Cu/PTFE composites were improved by 32.9% and 75.7%, respectively.
Key words: polytetrafluoroethylene; three-dimensional skeleton; composites; mechanical and thermal properties;
tribology properties

聚四氟乙烯(PTFE)因其独特的物理和化学性能 [1-3] ， 的磨损量比纯PTFE降低了1~2个数量级. 由上述文献
作为1种性能优异的固体自润滑材料 [4-6] 被广泛应用于 可知，铜颗粒增强PTFE基复合材料在一定程度上改
滑动轴承材料中，例如关节轴承、轴承保持架和塑料 善了材料的力学性能、导热性能和摩擦磨损性能. 但
轴承 [7-9] . 但PTFE存在耐磨性差、机械强度低、导热性 由于在整体结构上，颗粒增强PTFE基复合材料存在
差以及在外力作用下有较大的黏弹性变形等问题 [10-11] ， 增强相与基体PTFE在三维空间上不连续的问题，从
从而限制了其应用. 为了提升PTFE的使用性能，通常 而导致其复合材料的承载能力、导热性能和耐磨性能
采用无机填料 [12-14] 和有机填料 [15-17] 对PTFE进行改性， 方面的提高仍十分有限.
来提高PTFE的耐磨性能、力学性能以及导热性能，获 近几十年来，兴起了1种金属骨架新型功能材料，
[18]
得综合性能良好的PTFE基复合材料. 杨红波等 分别 因其优异的导热、承载和减震等物理性质 [20-24] ，被广
采用等体积含量的碳纤维(CF)、硅灰石纤维(WF)、聚 泛应用于复合材料中. 在聚合物基复合材料中，三维
[25]
酰亚胺(PI)、聚苯酯(POB)和铜粉(Cu)5种填料对PTFE 金属骨架材料也得到了广泛关注. 刘洋等 使用真空
进行改性，并对比研究了不同填料对PTFE力学性能、 灌注的方法制备了泡沫镍/环氧树脂复合材料(也称双
导热性能和摩擦学性能的影响，结果表明铜粉增强 连续相复合材料)，研究了泡沫镍对双连续相镍/环氧
PTFE基复合材料的力学性能且导热性能最优，相对于 树脂复合材料力学性能的影响，结果表明泡沫镍的三
[19]
PTFE材料其耐磨性得到显著提升. 张招柱等 研究了 维骨架结构有效提高了复合材料的抗拉强度，且双连
金属Cu、Pb及Ni填充改性PTFE基复合材料的摩擦磨 续相复合材料的弹性模量相较于聚合物相有一定程
[26]
损性能，结果表明金属填料降低了PTFE基复合材料的 度增加. Wang等 采用真空浸渍法制备了泡沫铜/聚
摩擦系数，也大大改善了PTFE基复合材料的耐磨性， 酰亚胺复合材料，并研究了泡沫铜对聚酰亚胺基复合
并且金属填料Cu的减磨效果最好，使PTFE复合材料 材料性能的影响，结果表明与不含泡沫铜的聚酰亚胺