Study on Ultrasonic Cavitation Mechanism of Honing

Ultrasonic cavitation is an extremely complex physical phenomenon. It displays a series of nonlinear dynamics as the bubbles oscillating, growth, shrinkage and even collapse. For ultrasonic honing, it causes the device to generate chatter and noise because of the cavitation effect, and even generates denudation on the workpiece surface. In this paper, it describes the cavitation mechanism in ultrasonic honing, and analysises the acoustic pressure of the formation of cavitation from the numerical, furthermore it experimentally demonstrated. It also analyzes the nonlinear oscillation of cavitation bubbles for the impact on the ultrasonic honing chatter. Through studying on ultrasonic cavitation mechanism of honing, it provided a theoretical basis to solution the problem of the ultrasonic honing chatter and improves the level of precision and ultra precision machining.

Download Full-text

On the impact of ultrasonic cavitation bubbles

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406211414769 ◽

2011 ◽

Vol 226 (3) ◽

pp. 681-694 ◽

Cited By ~ 14

Author(s):

A Abdullah ◽

M Malaki ◽

E Baghizadeh

Keyword(s):

Solid Surface ◽

Acoustic Pressure ◽

Deformation Energy ◽

Ultrasonic Cavitation ◽

Experimental Results ◽

Pressure Amplitude ◽

Aluminium Foil ◽

Numerical Studies ◽

The Impact ◽

Good Agreement

The main purpose of this study was to determine the impulse of a bubble on a solid surface or the amount of energy transmitted to the surface by the bubble. To do this, the results of previous numerical studies were used to derive a relationship between the speed of microjet and acoustic pressure amplitude. It was found that the speed of microjet is proportional to the logarithm of the acoustic pressure amplitude. Aluminium foil specimens were exposed to cavitation for 3 s and the dimensions of pits generated on specimens were measured. Then, the deformation energy of each pit and the corresponding impulse were calculated. The trend of experimental results was in a good agreement with the theoretical ones but their exact values were not.

Download Full-text

Cavitation Effect in Ultrasonic-Assisted Electrolytic In-Process Dressing Grinding of Nanocomposite Ceramics

Materials ◽

10.3390/ma14195611 ◽

2021 ◽

Vol 14 (19) ◽

pp. 5611

Author(s):

Guangxi Li ◽

Fan Chen ◽

Wenbo Bie ◽

Bo Zhao ◽

Zongxia Fu ◽

...

Keyword(s):

Ultrasonic Cavitation ◽

Grinding Wheel ◽

Workpiece Surface ◽

Elid Grinding ◽

Cavitation Effect ◽

Ultrasonic Assisted ◽

Hard And Brittle Materials ◽

Cavitation Threshold ◽

Grain Distribution ◽

Experimental Substantiation

Ultrasonic-assisted electrolytic in-process dressing (UA-ELID) grinding is a promising technology that uses a metal-bonded diamond grinding wheel to achieve a mirror surface finish on hard and brittle materials. In this paper, the UA-ELID grinding was applied to nanocomposite ceramic for investigating the cavitation effect on the processing performance. Firstly, the ultrasonic cavitation theory was utilized to define the cavitation threshold, collapse of cavitation bubbles, and variation of their radii. Next, the online monitoring system was designed to observe the ultrasonic cavitation under different ultrasonic amplitude for the actual UA-ELID grinding test. A strong effect of ultrasonic cavitation on the grinding wheel surface and the formed oxide film was experimentally proved. Besides, under the action of ultrasonic vibration, the dressing effect of the grinding wheel was improved, and the sharpness of grain increased by 43.2%, and the grain distribution was dramatically changed with the increase of ultrasonic amplitude. Compared with the conventional ELID (C-ELID) grinding, the average protrusion height increased by 14.2%, while the average grain spacing dropped by 21.2%. The UA-ELID grinding reduced the workpiece surface roughness Rz and Ra by 54.2% and 46.5%, respectively, and increased the surface residual compressive stress by 44.5%. The surface morphology observation revealed a change in the material removal mechanism and improvement of the surface quality by ultrasonic cavitation effect. These findings are considered instrumental in theoretical and experimental substantiation of the optimal UA-ELID grinding parameters for the processing of nanocomposite ceramics.

Download Full-text

A Self-Established “Machining-Measurement-Evaluation” Integrated Platform for Taper Cutting Experiments and Applications

Micromachines ◽

10.3390/mi12080929 ◽

2021 ◽

Vol 12 (8) ◽

pp. 929

Author(s):

Xudong Yang ◽

Zexiao Li ◽

Linlin Zhu ◽

Yuchu Dong ◽

Lei Liu ◽

...

Keyword(s):

Three Dimensional ◽

Precision Machining ◽

Two Dimensional ◽

Dimensional Image ◽

Two Dimensional Image ◽

Integrated Platform ◽

Hard And Brittle Materials ◽

Ultra Precision ◽

Cutting Experiments

Taper-cutting experiments are important means of exploring the nano-cutting mechanisms of hard and brittle materials. Under current cutting conditions, the brittle-ductile transition depth (BDTD) of a material can be obtained through a taper-cutting experiment. However, taper-cutting experiments mostly rely on ultra-precision machining tools, which have a low efficiency and high cost, and it is thus difficult to realize in situ measurements. For taper-cut surfaces, three-dimensional microscopy and two-dimensional image calculation methods are generally used to obtain the BDTDs of materials, which have a great degree of subjectivity, leading to low accuracy. In this paper, an integrated system-processing platform is designed and established in order to realize the processing, measurement, and evaluation of taper-cutting experiments on hard and brittle materials. A spectral confocal sensor is introduced to assist in the assembly and adjustment of the workpiece. This system can directly perform taper-cutting experiments rather than using ultra-precision machining tools, and a small white light interference sensor is integrated for in situ measurement of the three-dimensional topography of the cutting surface. A method for the calculation of BDTD is proposed in order to accurately obtain the BDTDs of materials based on three-dimensional data that are supplemented by two-dimensional images. The results show that the cutting effects of the integrated platform on taper cutting have a strong agreement with the effects of ultra-precision machining tools, thus proving the stability and reliability of the integrated platform. The two-dimensional image measurement results show that the proposed measurement method is accurate and feasible. Finally, microstructure arrays were fabricated on the integrated platform as a typical case of a high-precision application.

Download Full-text

An Investigation of the Cutting Strategy for the Machining of Polar Microstructures Used in Ultra-Precision Machining Optical Precision Measurement

Micromachines ◽

10.3390/mi12070755 ◽

2021 ◽

Vol 12 (7) ◽

pp. 755

Author(s):

Chen-Yang Zhao ◽

Chi-Fai Cheung ◽

Wen-Peng Fu

Keyword(s):

Precision Measurement ◽

Detection Algorithm ◽

Surface Generation ◽

Precision Machining ◽

Tool Geometry ◽

Depth Of Cut ◽

Machining Parameters ◽

Ultra Precision ◽

Transition Points ◽

Cutting Strategy

In this paper, an investigation of cutting strategy is presented for the optimization of machining parameters in the ultra-precision machining of polar microstructures, which are used for optical precision measurement. The critical machining parameters affecting the surface generation and surface quality in the machining of polar microstructures are studied. Hence, the critical ranges of machining parameters have been determined through a series of cutting simulations, as well as cutting experiments. First of all, the influence of field of view (FOV) is investigated. After that, theoretical modeling of polar microstructures is built to generate the simulated surface topography of polar microstructures. A feature point detection algorithm is built for image processing of polar microstructures. Hence, an experimental investigation of the influence of cutting tool geometry, depth of cut, and groove spacing of polar microstructures was conducted. There are transition points from which the patterns of surface generation of polar microstructures vary with the machining parameters. The optimization of machining parameters and determination of the optimized cutting strategy are undertaken in the ultra-precision machining of polar microstructures.

Download Full-text

Two tool path generation methods for ultra-precision machining of off-axis convex ellipsoidal surface

Proceedings of the Institution of Mechanical Engineers Part N Journal of Nanoengineering and Nanosystems ◽

10.1177/1740349914530682 ◽

2014 ◽

Vol 229 (4) ◽

pp. 147-153 ◽

Cited By ~ 2

Author(s):

Shijun Ji ◽

Huijuan Yu ◽

Ji Zhao

Keyword(s):

Tool Path ◽

Tool Path Generation ◽

Precision Machining ◽

Path Generation ◽

Ellipsoidal Surface ◽

Ultra Precision

Download Full-text

Experimental Examination of the Impact of Tool Radius on Specific Energy in Microcutting of Granite

Journal of Engineering Materials and Technology ◽

10.1115/1.4036585 ◽

2017 ◽

Vol 139 (4) ◽

Cited By ~ 1

Author(s):

Miloš Pjević ◽

Ljubodrag Tanović ◽

Goran Mladenović ◽

Biljana Marković

Keyword(s):

Cutting Force ◽

Penetration Depth ◽

Specific Energy ◽

Brittle Materials ◽

Experimental Examination ◽

Workpiece Surface ◽

Different Shapes ◽

Tip Radius ◽

The Impact ◽

Force Intensity

The paper presents experimental results of microcutting brittle materials (granite). The analysis was conceived on the observed interaction between the workpiece and two tools of different shapes. Experiment was based on scratching the workpiece surface with diamond tools. Applied tools had tip radius R0.2 and R0.15 mm. The experiment determined the changes in the value of perpendicular and tangential components of the cutting force based on the geometric properties of tools, as well as the changes of the specific energy of microcutting granite (Jošanica and Bukovik types). The experiment has shown that reduction of tool radius causes reduction of the cutting force intensity and specific cutting energy. Because of its physical/mechanical properties, more energy is required for micromachining granite “Jošanica” than “Bukovik.” Based on the topography of the surface, the value of critical tool penetration depth was established, after which the brittle fracture is no longer present. For granite “Jošanica” values of critical penetration depth are 6 and 5 μm when micromachining with tools R0.2 and R0.15 mm, while for Bukovik those values are 6.5 and 5.5 μm. The paper should form the basis for understanding the phenomena which occur during microcutting brittle materials.

Download Full-text

Residual stresses with different tool flank wear lengths in the ultra-precision machining of NiP alloys

Journal of Materials Processing Technology ◽

10.1016/0924-0136(95)02251-1 ◽

1997 ◽

Vol 65 (1-3) ◽

pp. 116-126 ◽

Cited By ~ 20

Author(s):

Zone-Ching Lin ◽

Wun-Ling Lai ◽

H.Y. Lin ◽

C.R. Liu

Keyword(s):

Residual Stresses ◽

Flank Wear ◽

Precision Machining ◽

Tool Flank Wear ◽

Ultra Precision

Download Full-text

Study on Ultra-Precision Ball Surface Floating Polishing Kinematics Mechanism

Materials Science Forum ◽

10.4028/www.scientific.net/msf.532-533.109 ◽

2006 ◽

Vol 532-533 ◽

pp. 109-112

Author(s):

Xun Lv ◽

Ju Long Yuan ◽

Dong Hui Wen ◽

Qian Fa Deng ◽

Fei Yan Lou

Keyword(s):

Chemical Conversion ◽

Processing Parameters ◽

Precision Machining ◽

High Tech ◽

National Defense ◽

Ball Surface ◽

Angular Velocities ◽

Ultra Precision ◽

Relationship Of ◽

The Mathematical Model

The high precision balls are requested in national defense, astronautics and high-tech commercial domain urgently. Conventional precision machining methods are sensitive to uniformity of abrasives and machining environment. After precision machining, there are easily to produce thick damaged layer on the ball surface because of machining stress and chemical conversion. On the basis of the floating polishing mechanism, a new scatheless ultra-precision polishing method of ball surface can solve the problems of abrasives uniformity effectively and damaged layer. In order to ensure that the new polishing method polishes ball surface equally, the appropriate angular velocities of the ball should be selected. This paper sets up the mathematical model about the motion of ball. By analyzing and simulating the relationship of the angular velocities, the best processing parameters are acquired.

Download Full-text