Liu Xianfu, Zhang Jianhua, Li Li
School of Mechanical Engineering, Shandong University of Technology, Zibo 255000, China.
Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education of China, School of Mechanical Engineering, Shandong University, Jinan 250061, China.
Micromachines (Basel). 2021 Nov 14;12(11):1398. doi: 10.3390/mi12111398.
The processing method, one-dimensional ultrasonic vibration-assisted turning (1D UVAT), is a potential and efficient way for fabricating a micro-textured surface. This paper aims at exploring the surface integrity and friction performance of brass H62 textured by the 1D UVAT. Four micro-textured surfaces with a specific distribution, size, and shape of dimples were fabricated by optimizing processing parameters, and the corresponding surface topography, subsurface microstructure, and surface roughness were observed and analyzed. A series of friction tests were carried out under oil-lubricating conditions to research the friction performance of micro-textured surfaces. The results show that the reason for the deviation between theoretical and experimental values of dimple depth was further revealed by observing the corresponding subsurface microstructure. The surface roughness of the micro-textured surfaces prepared is related to the number of micro-dimples per unit area and dimple size, which is greater than the surface generated by conventional turning. Compared with the polished surface and micro-grooved surface, the micro-textured surfaces have better friction performance with a lower frictional coefficient (COF) and wear degree. For the micro-textured surface fabricated by 1D UVAT, the number of micro-dimples per unit area has a great effect on the friction performance, and choosing a larger number is more conducive to improving the friction performance under the oil-lubricating condition. Consequently, this study proves that the proposed 1D UVAT can be a feasible candidate for preparing a micro-textured surface with better tribological property.
加工方法——一维超声振动辅助车削(1D UVAT),是制造微织构表面的一种有潜力且高效的方法。本文旨在探究经1D UVAT加工的H62黄铜的表面完整性和摩擦性能。通过优化加工参数制备了四个具有特定分布、尺寸和形状凹坑的微织构表面,并对相应的表面形貌、亚表面微观结构和表面粗糙度进行了观察与分析。在油润滑条件下进行了一系列摩擦试验,以研究微织构表面的摩擦性能。结果表明,通过观察相应的亚表面微观结构,进一步揭示了凹坑深度理论值与实验值偏差的原因。所制备的微织构表面的粗糙度与单位面积内微凹坑数量和凹坑尺寸有关,且大于传统车削加工产生的表面。与抛光表面和微槽表面相比,微织构表面具有更好的摩擦性能,摩擦系数(COF)和磨损程度更低。对于经1D UVAT制备的微织构表面,单位面积内微凹坑数量对摩擦性能有很大影响,在油润滑条件下选择较大数量更有利于提高摩擦性能。因此,本研究证明所提出的1D UVAT可作为制备具有更好摩擦学性能的微织构表面的一种可行方法。