Page 152 - 《摩擦学学报》2021年第6期

第 6 期 石佩璎, 等: MoO 3 -ZnO/镍基复合涂层制备及其摩擦学性能研究 937

cross-sectional microstructure of composite coatings exhibited a lamellar structure with several pores and un-melted

particles. The content of Mo and Zn element in the composite coatings increased with the increasing content of MoO 3
and ZnO powders in feedstock powders. The friction coefficients and wear rates of the composite coating were higher
than that of the Ni–5%Al(mass fraction) metal matrix at room temperature and 400 ℃. Moreover, the lubrication and
wear resistance of the composite coatings deteriorated with the increase of oxides content, the wear mechanism was
mainly manifested as abrasive wear and adhesive wear. The high coefficient of friction at room temperature was related
to the lack of effective lubricants in the coatings, whereas the added oxides were lubricious at high temperatures. The
high wear rates of composite coatings at 400 ℃ was mainly due to the softening effect of materials and the wear before
the formation of a stable oxide layer. At 800 ℃, the tribological properties can be effectively improved by the addition
of MoO 3 and ZnO. In particular, the composite coating with the addition of 5% MoO 3 and 5% ZnO exhibited the lowest
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friction coefficient (0.28) and the wear rate [4.22×10 mm /(N·m)]. And the wear rates of composite coatings increased
with the increasing content of MoO 3 and ZnO powders in feedstock powders, which was related to the increasing peeling
areas on the worn surface of the composite coatings. A protective tribo-layer was observed on both coatings and
counterpart Al 2 O 3 balls at 800 ℃. Furthermore, the elements of composite coatings (Mo and Zn) transferred to the worn
surface of corresponding counterpart balls and were compacted to a relatively smooth film, which prevented the direct
contact between the coatings and the Al 2 O 3 ball, thus providing a low shearing interface and reduce the friction. The
excellent high temperature tribological performance can be attributed to the synergistic effect of binary oxides (NiO,
MoO 3 , ZnO) and ternary oxides (ZnMoO 4 and NiMoO 4 ) on the worn surfaces of both composite coatings and
counterpart Al 2 O 3 balls.
Key words: oxides; composite coating; atmospheric plasma spray; tribological properties; wear mechanism

机械运动部件在高温的摩擦磨损行为对航天航 有效改善Ni基涂层的高温润滑性能和耐磨性能. 众多
空发动机、燃气轮机、核能及煤化工等高温装备系统 氧化物中，MoO 的离子势较高(8.2)，而ZnO的离子势
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的可靠性和寿命影响巨大. 传统的润滑油和润滑脂流 为2.7，两者差异较大，因此MoO 和ZnO生成的氧化物
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体润滑剂在温度小于200 ℃时具有优异的润滑性能， ZnMoO 是潜在的高温润滑剂 ；另外Essa等 研究了
[7]
[17]
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但当温度继续升高到大于300 ℃，它们将发生氧化而 MoS 和ZnO的添加对M50合金钢摩擦学性能的影响，
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[1]
失去润滑性能 . 常见的高温固体润滑剂主要有氟化 两者形成的氧化物ZnMoO 以及MoS2和ZnO的协同效
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物、氧化物和无机含氧酸盐等 [2-5] . 关于氧化物的润滑 应，使其高温下表现出优异的摩擦学性能. 但以MoO -
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[6-7] [8]
机制，Erdemir 和Prakash等 提出了晶体化学理论， ZnO金属氧化物制备的金属陶瓷复合涂层的研究尚未
引入了离子势的概念，对于单一氧化物，离子势越高， 报道，为了探索研究多元金属氧化物型高温润滑剂体
润滑性能越优异，而对于氧化物体系，离子势差异越 系，本文作者继续利用等离子喷涂的方法，研究了
[9]
大，该系统的润滑性能越好. 陈建敏等 通过放电等离 MoO -ZnO氧化物体系的镍基金属陶瓷复合涂层的摩
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子烧结工艺制备了Ni-Mo-PbO复合材料，PbO的加入 擦学性能，为发展新型高温固体润滑剂及其自润滑涂
可以明显改善复合材料的高温摩擦磨损性能，500 ℃ 层提供试验和理论依据.

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时，摩擦系数低至0.09，磨损率低至2.8×10 mm /(N·m).
1 试验部分
[10]
欧阳等 采用水热法制备了BaMoO 粉末，采用热压
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烧结的方法制备了NiCr-BaMoO 自润滑复合材料，从 1.1 涂层制备
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室温到600 ℃摩擦系数为0.26~0.30，磨损率为10 ~ 通常粒径范围在30~120 μm的粉末可以用于等离
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10 mm /(N·m). 其团队还研究了火花等离子体烧结 子喷涂，商用的ZnO粉末颗粒尺寸约为100~500 nm ，
[16]
制备的ZrO (Y O )-BaCrO 自润滑复合材料与低压等 因此将商用ZnO粉末加入到75 ℃的质量分数为5%的
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离子喷涂制备的ZrO -BaCrO 涂层，均在300~800 ℃的 聚乙烯醇水溶液中，磁力搅拌1 h后，在烘箱中于100 ℃
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[11]
广泛温度范围内表现出良好的摩擦特性 . 课题组之 烘干10 h，随后机械破碎并过筛得到20~120 μm的团
前的研究结果表明，真空浸渍的Ag/Ag MoO 可以有 聚粉末. 商用的MoO 过筛得到粒径范围在20~120 μm
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效抑制氧化钇稳定氧化锆(YSZ)涂层的脆性断裂，改 的粉末. 采用GH4169高温合金(Φ24 mm×8 mm)作为
[12]
[14]
善其摩擦学性能 ；另外，TiO -Bi O 3 [13] 、TiO -BaO 、 基底，沉积前利用YQ-9060A 型喷砂设备在0.55 MPa
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[16]
[15]
MoO -CuO 和TiO -ZnO 系列氧化物的添加，均可 的压力下对基底进行喷砂处理，随后依次用丙酮和酒
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