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

The paper proposes a three-degrees-of-freedom flexible nano-positioning stage constructed from compliant flexures and piezoelectric thin-sheet actuators, featuring a compact size and fast dynamic responses, which can be extensively applied to the typical micro/nano-positioning applications. Meanwhile, the dynamic model of the flexible PZT nano-positioning with distributed parameter characteristics is established to distinctly reflect the piezoelectric–mechanical coupling relationship between the four flexible PZT actuators and the three outputs of such a system. Furthermore, the attitude decoupling control for the 3-DOF flexible piezoelectric nano-positioning stage is achieved by the Active Disturbance Rejection Control (ADRC) method to compensate for the positioning errors in the actual positioning process. After this, a real-time experimental apparatus with two Position-Sensitive Detectors (PSDs) is also proposed and fabricated to test the three outputs of the flexible piezoelectric thin-sheet (PZT-5A) nano-positioning stage and validate the effectiveness of the dynamic modeling method and attitude decoupling control in the piezoelectric nano-positioning stage ranges.

Fabricating micro-textures with specific parameters (size, shape, and distribution) on the surface of mechanical components has the potential to improve the tribological performance. When the ultrasonic vibration is applied to depth direction of turning, the micro-textured surfaces with specific dimples can be generated in a simple and effective way. Under the intermittent cutting condition, the generation mechanism of the micro-textured surface, processed by this one-dimensional ultrasonic vibration-assisted turning (1D UVAT), was further carried out. A novel theoretical model was firstly proposed from the perspective of geometric kinematics, which can reveal the influence of three intersection states between the flank face and cutting trace (η₁ < tan α, η₁ > tan α > η₂ and η₂ > tan α) on the size, shape, and distribution of micro-dimples, generated under intermittent cutting conditions. Then, a simulation model was built to predict the surface topography and dimple profile under different processing parameters. The results show that the processing parameters, including clearance angle, spindle speed, and vibration amplitude, have an important influence on the intersection state. By choosing the proper clearance angle, spindle speed, or vibration amplitude, the different intersection states can be realized, and the corresponding size, shape, and distribution of micro-dimples will be changed accordingly. With the increase of the nose radius and feed rate, the dimple width and distance between adjacent dimples along feed direction can both increase accordingly. The simulation results not only confirm the feasibility of the proposed theoretical model, but also show that the discrete or continuous micro-dimples, with different sizes and specific shapes, can be controllably generated on cylindrical surface by 1D UVAT under intermittent cutting conditions.

To further enhance the performance of the fast tool servo (FTS) system in terms of stroke, load capacity, and application area, this paper proposes a novel fast tool servo device driven by a voice coil motor (VCM), based on a three-segment uniform corrugated flexure (CF) guiding mechanism, with a large stroke, high accuracy, and high dynamics. To describe the unified static characteristics of such device, the compliance matrix method is applied to establish its model, where the influence of CF beam structural parameters on the FTS device is investigated in detail. Furthermore, resolution and positioning accuracy tests are conducted to validate the features of the system. The testing results indicate that the maximum stroke of the FTS device is up to 3.5 mm and the positioning resolution values are 3.6 μm and 2.4 μm for positive and negative stroke, respectively, which further verifies the device’s effectiveness and promising application prospect in ultra-precision microstructure machining.