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作者简介:

徐宇轩,男,1997年出生,博士研究生。主要研究方向为高性能粉末冶金摩擦材料。E-mail: 1014648438@qq.com

通讯作者:

姚萍屏,男,1969年出生,博士,教授,博士研究生导师。主要研究方向为高性能摩擦学材料和电磁发射摩擦学。E-mail: yaopingpingxx@sohu.com

中图分类号:TG156;TB114

DOI:10.11933/j.issn.1007-9289.20230508001

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目录contents

    摘要

    WC 与 Cu 界面结合强度不足严重影响铜基复合材料的摩擦磨损性能,但业内尚未有良好的界面调控措施以优化性能。采用铜表面改性 WC 颗粒改善 WC 与 Cu 基体界面,经粉末冶金工艺制备 Cu 改性 WC 颗粒增强铜基复合材料,开展复合材料的微结构表征与摩擦学性能研究。研究表明,Cu 改性 WC 颗粒可良好地嵌入铜基体,颗粒与 Cu 基体界面较基体弹性恢复能力提升 33%,硬度提升 20%。15 wt.% Cu 改性 WC 增强铜基复合材料具有最佳的物理性能与摩擦学特性,较纯铜粉末冶金材料体积密度提升 8%,布氏硬度提升 15%,摩擦因数波动幅度最小并稳定在 0.75,磨损量最小为 0.075 mm3 ,磨痕轮廓圆滑,磨损面最完整且大面积成膜。随 Cu 改性 WC 含量增大,主要磨损机制由黏着磨损转变为剥离磨损,Cu 改性 WC 颗粒促进摩擦转移层的形成,抑制磨损面裂纹的横向扩展。Cu 改性 WC 颗粒与铜基体界面结合强度显著提升,15 wt.% 复合材料抑制黏着磨损与疲劳磨损,摩擦学性能优异。采用 Cu 改性 WC 颗粒增强铜基摩擦材料有望成为优化 WC 与 Cu 基体界面提升铜基复合材料摩擦学性能的重要备选途径。

    Abstract

    Tungsten carbide (WC) particle-reinforced composites are widely used owing to their excellent mechanical properties. The limited solubility of WC in Cu and the weak mechanical interface between the WC particles and the Cu matrix are the main factors contributing to the suboptimal tribological performance of these composites. To address this issue, the surface modification of WC particles is crucial for optimizing the interface and enhancing the bonding strength between the particles and the matrix. In this study, porous spherical WC particles were modified with Cu via spraying and sintering. Cu matrix composites reinforced with five different amounts of Cu-modified WC particles (0 and 5 wt.%, 10 wt.%, 15 wt.%, 20 wt.%, and 25 wt.%) were prepared using a powder metallurgy technique. The mechanical and tribological properties of the Cu matrix composites were tested using a hardness tester and a UMT3 friction tester. Nanoindentation and scanning electron microscope (SEM) line scanning were used to characterize the interface of the Cu-mdified WC particles and Cu matrix. Macro-and microstructural characterization and tribological performance analysis were performed on Cu matrix composites reinforced with Cu-modified WC particles. The results of this study indicate that the Cu-modified WC particles were effectively embedded in the Cu matrix, resulting in the formation of a submicron diffusion layer at the interface between the modified particles and the matrix. This modification process led to a 33% increase in elastic resilience and a 20% increase in hardness at the interface. Microcracks within the particles as well as between the particles and Cu matrix contribute to an increase in porosity. Among the tested composites, the Cu-matrix composite reinforced with 15 wt.% Cu-modified WC particles exhibited superior tribological performance. The friction coefficients of this composite showed minimal fluctuations, stabilizing at approximately 0.75, with wear volumes decreasing to 0.075 mm3 . The worn surfaces of 15 wt.% Cu-modified WC reinforced composite displayed fairly smooth contours, the shallowest grinding crack, and large-scale continuous films. Furthermore, as the Cu-modified WC content increased, the main wear mechanism shifted from adhesive to abrasive wear at 15 wt.%, and eventually to fatigue wear at 25 wt.%. The surface friction transfer layers of the composites were characterized by the presence of Cu, Fe, O, and W. The Fe from the sliding friction pairs and absorbed oxygen contributed to the formation of a tribological film. Additionally, the presence of the modified particles causes deflection in the direction of the cracks and reduces their expansion at the corresponding locations. This research demonstrates a significant improvement in the interfacial bonding strength between the Cu-modified WC particles and Cu matrix. A composite material with 15 wt.% Cu-modified WC effectively inhibits adhesion wear and fatigue wear, resulting in excellent tribological properties. The utilization of Cu-modified WC particles to reinforce Cu-matrix composites offers a promising approach for optimizing the interface between WC and the Cu matrix, thereby enhancing the tribological properties of Cu-matrix composites. This paper has significant implications for the practical application of Cu-modified WC particles in Cu-matrix composites and provides a theoretical foundation for further research in this area.

  • 0 前言

  • 以铜为基体制备的铜基复合材料在航空航天、轨道交通等重要领域有着不可替代的作用。为提高铜基体的力学和摩擦学性能,往往在金属基体中掺杂硬质增强组元(金属、合金与陶瓷)[1-3]

  • 在金属材料中引入陶瓷颗粒作为增强相,通常被称为颗粒增强金属基复合材料,极硬极脆陶瓷颗粒的加入通常使复合材料硬度和耐磨性显著增加[4-5]。在以往的研究中,碳化钨(WC)颗粒增强铜基复合材料表现出较好的摩擦学性能[6-9],这是由于 WC 硬质颗粒具有高硬度高耐磨高稳定性等特点,可以在室温至 1 400℃范围内保持高硬度且无相变[810-11],复合效应使复合材料兼具高硬高强 WC 与高延展性 Cu 的优异性能。然而,WC 在铜中的溶解度有限,复合材料中两者由于未充分润湿易形成孔隙,且两者仅为简单的溶解与润湿界面[12-13]。此外,Cu 与 WC 软硬交替的性质加剧了复合材料微观上的不均匀性,应力在界面处的不均匀传递导致硬质颗粒的过度损伤。因此,WC 颗粒增强铜基复合材料在磨损过程中磨损面易出现大面积剥离、裂纹、破损,难以形成平整摩擦膜,摩擦因数过高且波动幅度大,磨损量较高[812-14]

  • 针对 WC 增强铜基复合材料的摩擦学性能不佳等问题,本文采用 Cu 改性 WC 颗粒增强铜基复合材料。为探明 Cu 改性 WC 颗粒对 Cu 基体微观结构与摩擦学性能的影响,制备了不同含量 Cu 改性 WC 颗粒增强铜基复合材料,并对复合材料的结构组织和摩擦学特性进行研究。研究结果可为 Cu 改性 WC 颗粒在铜基复合材料界面调控与力学、摩擦学性能优化提供重要的理论依据。

  • 1 制备和方法

  • 1.1 材料制备方法

  • 为研究 Cu 改性 WC 增强铜基复合材料的微观结构与摩擦学特性,将 Cu 改性 WC 颗粒含量为单一变量,采用粉末冶金方法制备 5 组不同含量 Cu 改性 WC(5 wt.%、10 wt.%、15 wt.%、20 wt.%、 25 wt.%)的 Cu 改性 WC 颗粒增强铜基复合材料。作为对比,采用电解铜粉制备纯铜粉末冶金材料。

  • Cu改性 WC 粉末由清河县安迪金属材料有限公司生产,工艺为先将 Cu 与 WC 粉末熔融制得前驱液体,随后经喷雾干燥球形化造粒,喷雾干燥过程中加入粘结剂,随后在高温下将粉末脱胶处理,充分将粘结剂裂解,最终对脱脂后团聚复合粉末进行高温烧结处理,使 WC 颗粒表面与 Cu 发生结合。

  • 表1 为试验用电解铜粉与 Cu 改性 WC 粉末的物理性能参数,试验用电解 Cu 粉的粒度与增强颗粒的粒度相近,以减少颗粒尺寸差异过大导致的混合不均匀与压粉偏析程度。颗粒增强铜基复合材料的具体工艺流程如下:采用电子天平秤量不同质量比金属粉末与增强颗粒粉末,添加 1 wt.%煤油后将混料置于滚筒混料机混合 6 h。

  • 表1 Cu 与 Cu 改性 WC 的物理参数

  • Table1 Physical parameters of the Cu and Cu modified WC

  • 试验用模具为 Φ33.5 mm 圆柱型钢模具,混合粉末于模具中经 40 MPa 压力下冷压成型,静置 8 h 后将压坯叠装在钟罩式加压烧结炉内进行氢气烧结。材料烧结温度为 970℃,烧结压力为 2.5 MPa,保温时间为 180 min。

  • 1.2 材料性能测试及结构表征

  • 采用阿基米德法测定制备样品的体积密度,用测量精度为 0.005 g 的艾锐普 XS-600W 密度仪进行测量,须分别测量烧结试样在空气中的质量以及在去离子水中的质量。烧结后试样的理论密度根据混合律计算得出,孔隙率为理论密度和体积密度的差与理论密度的商值:

  • ρa=ma×ρwma-mw
    (1)
  • ρi=1i=1n ωiρi
    (2)
  • 式中,ρa为体积密度,g / cm3ρw为水的密度,g / cm3ma 为烧结试样在空气中的质量,g;mw 为烧结试样在水中的质量,g;n 为组元总数;ωi 为各组元的质量百分数;ρi为各组元的理论密度,g / cm3

  • 采用布洛维三用硬度计(A-200,Italiana)测定材料布氏硬度。对抛光样品表面进行纳米压痕测试 (CSM UNHT,瑞士),压痕压头为 Berkoivh 压头,尖端尺寸<200 nm。在摩擦试验前,样品经 2000目砂纸打磨后抛光 30 min。采用 UMT-3 微摩擦磨损测试仪(CETR,USA)对铜基复合试样摩擦磨损性能进行测试。摩擦对偶为直径 Φ9.5 mm 的钢球 (HRC 62),摩擦界面状态为干磨擦。摩擦磨损试验参数为:试验温度为室温,加压载荷为 15 N,钢球往复行程为 10 mm,转速为 200 r / min,磨损时间 15 min。每个试样分别在不同区域进行两次磨损试验。采用 Keyence VHX-5000 超景深三维显微系统 (Keyence,Japan)进行磨痕表面三维形貌表征,并对磨痕的截面积、长度和波形线进行测量记录,取 5 处不同位置截面积数据取平均值,计算磨痕体积估算值。采用 SEM(MIRA3 LMH,TESCAN 与 QUANTA FEG 250)对粉末、烧结态材料、磨损面的微观结构与化学组成进行表征。

  • 2 结果与讨论

  • 2.1 Cu 改性 WC 的微观形貌与结构表征

  • 图1 为 Cu 改性 WC 颗粒的 SEM-Mapping 图,球形(类球形)Cu 改性 WC 颗粒表面为不规则的粗糙纹理,并分布着不规则结构的孔隙。高倍扫描电子显微镜下 Cu 改性 WC 颗粒表面大面积连接区域为不规则叠层状结构与局部不规则凸起结构,不同大面积叠层状区域间为非平整地连续衔接。

  • 图1 Cu 改性 WC 粉末 SEM-Mapping 图

  • Fig.1 SEM-Mapping of the Cu modified WC powder

  • Cu 改性 WC 颗粒由于类球形的整体结构具有良好的流动性的同时,凭借表面高度不规整与多孔结构具有较高的比表面积,有利于烧结。如图1b EDS 点扫描所示, Cu、W、C 元素质量比为 1.73∶9 0.07∶8.20,表明 Cu 改性 WC 颗粒表面存在一定量 Cu,WC 颗粒表面具有改性效果。

  • 2.2 Cu 改性 WC 颗粒增强铜基复合材料微观结构

  • 为了对比分析颗粒对铜基复合材料结构的影响,观察 5 wt.%与 25 wt.%Cu 改性 WC 颗粒增强铜基复合材料的表面形貌。如图2a、2b 所示,5 wt.% Cu 改性 WC 增强铜基复合材料的基体组织结构整体较为完整,但可观察到部分小尺寸微孔。

  • Cu 改性 WC 颗粒镶嵌在铜基体内部构成增强相,部分颗粒间以及颗粒与基体间存在两种类别的孔隙与裂纹,一种为颗粒内部本身的不规则孔隙; 另一种为部分颗粒内部孔隙延伸至与基体连接的边缘,接触界面处由于颗粒边缘孔隙的存在出现微孔的萌生。如图2c、2d 所示,较高含量增强颗粒与铜基体烧结融并后出现颗粒内部孔隙的相互连通,多个颗粒间形成新缺陷,生成较多大尺寸(10 μm 左右)三角裂纹。

  • 图2 不同含量 Cu 改性 WC 增强铜基复合材料表面 SEM

  • Fig.2 SEM of polished surfaces of Cu matrix composites with different contents of reinforced particle

  • 为探明 Cu 与 Cu 改性 WC 颗粒界面的结合特性,对 Cu 改性 WC 颗粒与铜基体形成的界面开展研究(图3)。研究表明,Cu 改性 WC 与基体结合较为紧密,通过对界面选定区域进行 EDS 线扫描分析(图3b),沿基体向 Cu 改性 WC 颗粒内部方向, Cu含量急剧下降的同时W含量在界面处急剧升高,在 4~4.5 μm 处出现过渡区,随后 Cu 与 W 信号曲线分别下降与上升至相对平衡阶段,平衡阶段内W、 Cu 元素信号的骤然波动来源于增强颗粒内部孔结构被基体铜润湿填充。

  • 图3 Cu 改性 WC 颗粒增强铜基复合材料 SEM 与界面特征

  • Fig.3 SEM of microstructure and interface characteristics of Cu modified WC reinforced Cu matrix composite

  • 为进一步探明 Cu 改性 WC 与 Cu 基体界面特性,开展了对基体、Cu 改性 WC 颗粒以及界面纳米压痕测试。如图4 所示,纳米压痕测试位置分别为 Cu 基体、颗粒与增强相界面处以及增强颗粒基体,载荷位移曲线表明在释放载荷后不同位置处发生不同程度的塑性变形。铜基体由于具有较低的强度与良好的延展性导致形变量最大,Cu 改性 WC 颗粒凭借高硬度高强度发生最小的塑性变形。而 Cu 与改性 WC 颗粒界面处的形变量位于增强相与基体相之间,在 0~210 nm 内载荷位移曲线斜率与 Cu 基体基本一致,表明变形首先发生在界面处的铜。而在大约 210 nm 处载荷位移曲线出现拐点,斜率介于增强颗粒与铜基体间,表明界面较基体具有更好的弹性恢复能力,该现象来源于复合材料微观上的协同效应[15-16]。图4c 为基体、界面与 Cu 改性 WC 颗粒硬度与弹性模量,三者硬度分别为 1.88、2.25、10.94 GPa,弹性模量分别为 185.08、126.33、324.90 GPa。 Cu 改性 WC 具有最高的硬度与弹性模量,界面处较基体具有较高的硬度,但弹性模量最小,这也说明了陶瓷颗粒增强金属复合材料的高硬度、低韧性特点。

  • 图4 Cu 改性 WC 颗粒增强铜基复合材料表面不同位置纳米压痕测试图

  • Fig.4 Nanoindentation of different points on Cu modified WC particle reinforced Cu matrix composites surface

  • 2.3 Cu 改性 WC 颗粒增强 Cu 基摩擦材料的物理性能与摩擦学特性

  • 图5a 为不同 Cu 改性 WC 颗粒含量铜基复合材料的体积密度与孔隙率。研究表明,铜基复合材料的体积密度随颗粒含量提升逐步增大,在添加量 10 wt.%后无明显变化,这是由硬质颗粒的压制性能低于 Cu 所致。然而孔隙率呈现先下降后升高的趋势,Cu 改性 WC 含量在 5 wt.%时最低为 3%,随后呈近线性升高,在 25 wt.%时达 12%。5 wt.% Cu 改性 WC 含量时,铜基体有效包裹增强颗粒,WC 比重大于 Cu 导致真孔隙率低。随硬质颗粒添加量增大,Cu 改性 WC 合金颗粒内部、颗粒间以及颗粒与基体间的缺陷暴露,促进三角、细长连通微裂纹的萌生与扩张,导致气孔率骤升。宏观硬度的逐步增高来源于 Cu 改性 WC 微观硬度的积累以及 Cu 改性 WC 作为硬质颗粒在基体中颗粒强化作用。此外,Cu 改性 WC 颗粒与基体界面结合较为理想,界面硬度高于基体,同步提高复合材料抵抗外力变形的能力,硬度升高。

  • 图5 不同 Cu 改性 WC 颗粒含量铜基复合材料物理性能

  • Fig.5 Physical properties of Cu composites with different contents of reinforced particle

  • 图6 为不同含量 Cu 改性 WC 颗粒增强铜基复合材料的滑动摩擦因数曲线。当材料中未添加和添加少量的 Cu 改性 WC 时,摩擦曲线波动相对较大,这是因为未添加和添加少量 Cu 改性 WC 时,复合材料的硬度相对较低,抗剪切能力较弱,黏着力较大导致不断形成基体的变形、转移,在摩擦过程中基体容易被硬质对偶带出,形成黏着磨损,摩擦表面起伏较大,导致摩擦曲线波动。当复合材料中的 Cu 改性 WC 含量在 10~20 wt.%时,摩擦曲线相比于低含量的 Cu 改性 WC 时较为稳定。这是由于 Cu 改性 WC 对基体的颗粒强化作用使得基体硬度与抗剪切能力上升。当 Cu 改性 WC 含量达到 25 wt.%时,摩擦因数难以稳定并在长时间摩擦后出现明显波动,过多的硬质颗粒在横向力的作用下不断挤入与切削进入基体相,在与基体内原有的颗粒碰撞堆积后发生严重变形导致摩擦因数更加不稳定。磨损量随 Cu 改性 WC 颗粒的添加量增大呈现先降低后上升的趋势,在 15 wt.%时磨损量最低,随后磨损量升至 0.102 mm3 与 0.117 mm3,均大于纯铜基体材料的磨损量,表明局部团聚的硬质颗粒在切削作用下夹带基体排出,呈现较大的破坏性。因此,15 wt.%含量 Cu 改性 WC 颗粒增强铜基复合材料的摩擦学性能最佳。

  • 图6 不同增强颗粒含量铜基复合材料的摩擦学性能

  • Fig.6 Tribology properties of Cu composites reinforced by different contents of Reinforced Particle

  • 图7 为不同 Cu 改性 WC 含量铜基复合材料的摩痕三维景深形貌图与磨痕轮廓图。未添加 Cu 改性 WC 颗粒时,浅绿色区域较多且磨痕底部为浅蓝色,深色区域集中在磨痕两侧,表明摩擦过程中铜基体发生堆积挤压与变形至两侧,磨痕宽度大。如图7c~7f 所示,深蓝竖长区域为磨痕较深的犁沟。当 Cu 改性 WC 含量为 15 wt.%时,磨损面出现大面积连续区域,磨痕宽度、深度与截面面积最小,磨损面连续性较好,材料损失少,与平均磨损量计算结果吻合,磨痕底部轮廓平滑,无突出峰,表明在摩擦接触点处基体铜塑形流动下,Cu 改性 WC 颗粒与基体组成黏着点的循环剪切与滑动较为平衡,对材料损伤最小。而随着 Cu 改性 WC 含量进一步增大,磨痕内部出现明显分层,主要表现为大面积绿色区域-浅蓝色过渡区-深蓝色沟槽区,该现象在 25 wt.% Cu 改性 WC 含量时最为明显,表明高含量 Cu 改性 WC 颗粒导致滑动接触力分布更为不均匀,材料的变形与损伤更为严重。

  • 图7 不同含量 Cu 改性 WC 颗粒增强 Cu 基复合材料磨痕的三维形态与二维轮廓图

  • Fig.7 3D morphologies and 2D outline of worn surface of Cu matrix composites with different contents of Cu modified WC particles

  • 图8 为摩擦试验后试样磨痕表面 SEM 图像。所有滑动摩擦表面均具有典型的磨损特征:擦伤、剥落与塑性变形。未添加 Cu 改性 WC 增强颗粒的样品表面呈波浪状起伏并存在细小的剥落坑,细长的沟槽间为铜基体构成的凸起区域,即铜挤压转移后的塑性变形区,因此出现垂直于滑移方向的堆叠式细裂纹。5 wt.%增强颗粒含量时材料磨痕表面由于硬质颗粒磨粒磨损导致擦伤出现小部分犁沟,而表面较大的剥落区和小面积的平面结构是由软基体发生大量黏着磨损所导致。15 wt.% Cu 改性 WC 增强铜基复合材料磨痕表面出现大面积连续光滑区域,细长犁沟为 Cu 改性 WC 硬质颗粒粗糙峰嵌入铜金属后,在滑动过程中推挤基体发生塑性变形移动形成的沟槽,主要磨损机制为硬质 WC 颗粒表面粗糙峰对软 Cu 基体的磨粒磨损[17]。然而,当 Cu 改性 WC 含量达 25 wt.% 时,除少量较浅的犁沟外,磨痕内出现大面积材料剥落,这是由于团聚的增强颗粒在垂直应力下同步压入基体,硬质颗粒与表面产生高应力碰撞,材料表面与亚表面层的组织与力学性能的过大差异导致在循环应力下形成剥离凹坑的主要形貌,主要磨损机制为疲劳磨损[18-19]

  • 因此,随 Cu 改性 WC 颗粒含量增大,材料的主导磨损机制有所不同,未添加增强颗粒时主要为黏着磨损,含量在 5~10 wt.%时磨损量降低但摩擦因数曲线出现小范围波动且,黏着力分量减少但仍导致过多材料的黏着损失。Cu 改性 WC 含量在 20~25 wt.%时,材料摩擦因数波动变大且磨损面损伤加剧,因此剪切发生在材料表层较深的位置,磨痕轮廓宽度变大,裂纹不断延展与扩张后贯穿,加重材料磨损脱落。15 wt.% Cu 改性 WC 颗粒增强铜基复合材磨损面具有大面积平整结构,表明黏着阻力减小,摩擦面材料在犁削力作用下稳定滑移,在此含量下由于颗粒对 Cu 基体的加工硬化效应,摩擦膜的硬度逐渐增大,材料耐磨性提高,塑性变形量降低,主要磨损机制为磨粒磨损。

  • 图8 不同颗粒含量增强铜基复合材料的磨损面 SEM 图

  • Fig.8 SEM images of worn surfaces of Cu composites with different Cu modified WC contents

  • 15 wt.% Cu 改性 WC 增强铜基复合材料具有最优异的摩擦学性能,然而除大面积摩擦膜外,仍可以在磨损面观察到几种损伤与缺陷。为进一步研究摩擦膜组织成分与磨损界面损伤特征,对磨损面三种典型特征微观区域进行高倍下 SEM-Mapping 表征。如图9a 所示,完整摩擦膜表面 Cu、Fe、O 元素分布均匀,零星分布的 W 元素聚集区域表明水平切削力下增强颗粒磨屑与基体形成较完整的转移层,Fe 来源于对偶钢球的转移, O 元素的均匀分布表明摩擦热使金属颗粒表面暴露的活性位点受到氧原子的附着,氧化膜防止金属与金属间的粘着并促进摩擦膜的形成[20]

  • 图9b 为典型的摩擦膜与磨损面裂纹的界面形貌,中心处增强颗粒内部孔隙被摩擦转移的基体铜填充,颗粒的左侧区域为完整的摩擦膜,右侧裂纹呈波浪状递进式分布,裂纹向垂直于滑动方向延展表明颗粒边缘处应力累积方向发生偏转。在远离增强颗粒处,材料转移积累后形成的较高微突体在往复摩擦力切削作用下生成更为严重的剥离坑[21]。图9c 中摩擦膜 Cu 与 Fe 元素呈现互补镶嵌分布来源于硬质颗粒对转移层的阻碍,在 W 聚集区域的周边 Fe 元素分布较少。O 元素的分布与 Fe 分布呈现高度吻合,表明氧原子主要附着在对偶 Fe 元素形成的转移层[22-23]

  • 图9 15 wt.% Cu 改性 WC 颗粒增强铜基复合材料磨损面微观结构背散射 SEM-Mapping 图

  • Fig.9 BSEM-Mapping images of microstructure of Cu matrix composites reinforced by 15 wt.% Cu modified WC worn surface

  • 综上所述,Cu 改性 WC 颗粒可显著提升铜基复合材料的基体硬度,在滑动摩擦过程中降低黏着力与犁削力从而提升复合材料摩擦学性能,硬质颗粒可抑制基体材料在磨损过程中裂纹的延展与扩张,颗粒碎屑与基体形成较好的机械转移层。

  • 3 结论

  • 研究不同含量 Cu 改性 WC 颗粒增强铜基复合材料的微观结构与摩擦学特性,获得主要结论如下:

  • (1)15wt.% Cu 改性 WC 增强铜基复合材料摩擦学性能优异,磨痕轮廓圆滑且无深沟槽,磨损面形成连续平整摩擦膜。

  • (2)随增强颗粒含量增大,铜基复合材料主要磨损机制从黏着磨损向磨粒磨损与疲劳磨损演变。 15 wt.%颗粒增强铜基复合材料抑制黏着磨损与疲劳磨损,主要发生磨粒磨损。

  • (3)Cu 改性 WC 颗粒增强铜基摩擦材料有望成为优化 WC 与 Cu 基体界面提升铜基复合材料摩擦学性能的重要备选途径。但后续须要对高温、载流摩擦条件下材料性能进行深入研究。

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    • [3] IDUSUYI N,OlLAYINKA J I.Dry sliding wear characteristics of aluminum metal matrix composites:A brief overview[J].Journal of Materials Research and Technology,2019,8(3):3338-3346.

    • [4] GONG T,YAO P,ZUO X,et al.Influence of WC carbide particle size on the microstructure and abrasive wear behavior of WC–10Co–4Cr coatings[J].Wear,2016,362-363:135-145.

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