Friction characteristics of mechanically microtextured metal surface in dry sliding
Friction characteristics of mechanically microtextured metal surface in dry sliding
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DOI：
10.1016/j.triboint.2019.02.042
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发表时间：
2020-09
影响因子：
6.2
通讯作者：
J. Shimizu;T. Nakayama;Kouta Watanabe;Takeyuki Yamamoto;T. Onuki;Hirotaka Ojima;Li-bo Zhou
中科院分区：
文献类型：
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作者：
J. Shimizu;T. Nakayama;Kouta Watanabe;Takeyuki Yamamoto;T. Onuki;Hirotaka Ojima;Li-bo Zhou
许多研究人员报道了通过应用各种纹理表面来改善摩擦学性能的方法。在这些研究中，大多数利用的表面都是用激光加工的。然而，这种纹理化方法存在一些问题，包括热效应、堆积的形成、可能的酒窝形状以及比机械方法效率低。传统的机械变形方法也存在一些问题。在本研究中，开发了一种替代方法，即利用立方体角金刚石压头在深度方向上以几十微米或更小的振幅振动辅助微切削。在这种技术中，可以通过在机器上进行正常的微切割来消除纹理中所有凹陷周围产生的堆积。利用所开发的方法，成功地制造出了黄铜板（c2680）的织构表面，在该表面上以数十微米的周期有规则地排列着转移压头尖端形状的微凹窝。为了验证它们的潜力，使用钢球（534A99）在采用该方法和常规切削方法织构的表面上进行了干滑动试验，以进行比较。随后，通过干滑动试验考察了去除堆积和凹窝密度的影响。通过监测摩擦系数、磨损率、观察磨损表面和产生的碎屑，对一系列滑动试验结果进行了分析。结果表明，区域密度相对较高的织构表面，如完全去除堆积的40%，由于周期性排列的微韧窝对产生的磨损碎片和实际接触面积的捕获和减少作用，摩擦系数和磨损最小。因此，所提出的织构方法可以作为一种新的候选方法来产生具有较好摩擦学性能的表面织构。同时，提高试样的旋转速度和/或振动频率可以提高织构效率。
Improving tribological properties by applying various textured surfaces have been reported by many researchers. In these studies, most utilized surfaces have been textured with lasers. However, such a texturing method contains several problems including thermal effects, formation of pileups, possible dimple shapes, and lower efficiency than mechanical methods. The traditional mechanical texturing methods also have some problems. In this study, an alternative method is developed by using vibration-assisted microcutting with a cube-corner diamond indenter which is vibrated in the depth direction with an amplitude of tens of microns or less. In this technique, the pileups generated around all the dimples in texturing can be removed by supplementally conducting a normal microcutting on the machine. By the developed method, textured surfaces of brass plate (c2680), in which micro dimples transferred tip shape of the indenter were regularly arranged at a period of tens of microns, were successfully manufactured. In order to verify their potentials, dry sliding tests using steel balls (534A99) were conducted on the surfaces textured by both the proposed and the normal cutting methods for comparison. Subsequently, the influence of the removing pileups and the dimple density were also examined through the dry sliding tests. A series of the sliding test results were analyzed through the monitored friction coefficients, wear rates, and observations of worn surfaces and generated debris. As a result, textured surface with a relatively high area density, such as 40% where pileups were completely removed showed the lowest friction coefficient and wear due to the trapping and reducing effects of the generated wear debris and real contact area by the periodically arranged micro dimples. Therefore, the proposed texturing method can be a new candidate to produce the surface textures for better tribological properties. Also, higher texturing efficiency could be realized by just applying higher sample rotation speed and/or vibration frequency.