Experimental Verification of Effect of Grinding Fluid Excited by Ultrasonic Vibration

2012 ◽  
Vol 523-524 ◽  
pp. 197-202 ◽  
Author(s):  
Jun Ishimatsu ◽  
Hiromi Isobe ◽  
Keisuke Hara

The grinding performance is strongly affected by grain condition. Especially loading directly raises the grinding force, reduces tool life and deteriorates accuracy of machining. In this study, ultrasonic exciter which applies vibration energy on grinding fluid was developed. The resonant frequency of 28kHz. The exciter is set between the fluid supplying nozzle and grinding wheel. The discharging grinding fluid from the nozzle is supplied to grinding wheel between the teeth of comb-shape horn. The performance is verified on surface grinding machine with vitrified WA grinding wheel. It was experimentally demonstrated that the excited grinding fluid prevented the loading and improved the surface roughness even for grinding of aluminum. And also improvement of surface roughness was recognized on alloy tool steel.

2016 ◽  
Vol 874 ◽  
pp. 308-312
Author(s):  
Hieu Nguyen Trung ◽  
Jun Ishimatsu ◽  
Hiromi Isobe

Ultrasonic excited fluid has been researched for machining of hard-to-grind materials. Ultrasonic vibration is applied to grinding fluid by an ultrasonic oscillating comb-shape effecter with integrated nozzle. Grinding fluid discharges from a nozzle placed between the comb’s feet and passes through the vacant space between comb teeth. By this setup, flowing grinding fluid can be continuously excited by ultrasonic vibration. Based on the principle of an ultrasonic washing machine, impulsive force caused by cavitation bubble will reduce the adhesion of chips on the cutting face of grain and chip pockets. Some effects of ultrasonic excited grinding fluid have been recorded such as reducing grinding heat in the case of grinding for Titanium alloy and decreasing in grinding force, improving surface roughness in the case of grinding for Aluminum and stainless alloy. However, the reason of better grinding performance is still unknown. Therefore, experiments conducted with different type of grinding fluids with and without ultrasonic vibration are needed. Pure Titanium, which considered a hard-to-cut material, is chosen as work material. Grinding forces and grinding heat during grinding will be measured and evaluated to clarify the mechanism of ultrasonic excited grinding fluid.


2022 ◽  
Vol 16 (1) ◽  
pp. 43-51
Author(s):  
Tatsuki Ikari ◽  
Takayuki Kitajima ◽  
Akinori Yui ◽  
◽  

Nickel-based heat-resistant alloys are widely used for fabricating the turbine blades in gas turbine engines. An increase in the number of such engines operated by air carriers will increase the demand for high-efficiency machining of nickel-based heat-resistant alloys. However, the high-efficiency grinding of nickel-based heat-resistant alloys is challenging because of their low thermal conductivity and thermal diffusivity, high chemical activity, large work-hardening properties, and high-temperature strength. In this work, the authors propose a high-efficiency grinding technique that uses speed-stroke grinding of nickel-based heat-resistant alloys, and aim to clarify the optimum grinding conditions for the proposed grinding method. The workpiece material is CMSX4 used for the turbine blades. A Cubitron + WA grinding wheel and WA grinding wheel mounted on a linear motor-driven surface grind machines are used for grinding, and the grinding force, surface roughness, and grinding ratio are investigated with the removal rate maintained constant. Two types of grinding fluid are prepared: solution and soluble. From the experiments, it is found that wet grinding features a lower grinding force, smaller surface roughness, and higher grinding ratio when compared to dry-cut grinding. The improvement in the grinding ratio at high table speeds is significant, and it is found to be greater for the soluble-type fluid than for the solution-type fluid.


2021 ◽  
Vol 11 (9) ◽  
pp. 4128
Author(s):  
Peng-Zhan Liu ◽  
Wen-Jun Zou ◽  
Jin Peng ◽  
Xu-Dong Song ◽  
Fu-Ren Xiao

Passive grinding is a new rail grinding strategy. In this work, the influence of grinding pressure on the removal behaviors of rail material in passive grinding was investigated by using a self-designed passive grinding simulator. Meanwhile, the surface morphology of the rail and grinding wheel were observed, and the grinding force and temperature were measured during the experiment. Results show that the increase of grinding pressure leads to the rise of rail removal rate, i.e., grinding efficiency, surface roughness, residual stress, grinding force and grinding temperature. Inversely, the enhancement of grinding pressure and grinding force will reduce the grinding ratio, which indicates that service life of grinding wheel decreases. The debris presents dissimilar morphology under different grinding pressure, which reflects the distinction in grinding process. Therefore, for rail passive grinding, the appropriate grinding pressure should be selected to balance the grinding quality and the use of grinding wheel.


2020 ◽  
Vol 4 (4) ◽  
pp. 114
Author(s):  
Akira Mizobuchi ◽  
Atsuyoshi Tashima

This study addresses the wet grinding of large stainless steel sheets, because it is difficult to subject them to dry grinding. Because stainless steel has a low thermal conductivity and a high coefficient of thermal expansion, it easily causes grinding burn and thermal deformation while dry grinding on the wheel without applying a cooling effect. Therefore, wet grinding is a better alternative. In this study, we made several types of grinding wheels, performed the wet grinding of stainless steel sheets, and identified the wheels most suitable for the process. As such, this study developed a special accessory that could be attached to a wet grinding workpiece. The attachment can maintain constant pressure, rotational speed, and supply grinding fluid during work. A set of experiments was conducted to see how some grinding wheels subjected to some grinding conditions affected the surface roughness of a workpiece made of a stainless steel sheet (SUS 304, according to Japanese Industrial Standards: JIS). It was found that the roughness of the sheet could be minimized when a polyvinyl alcohol (PVA) grinding wheel was used as the grinding wheel and tap water was used as the grinding fluid at an attachment pressure of 0.2 MPa and a rotational speed of 150 rpm. It was shown that a surface roughness of up to 0.3 μm in terms of the arithmetic average height could be achieved if the above conditions were satisfied during wet grinding. The final surface roughness was 0.03 μm after finish polishing by buffing. Since the wet grinding of steel has yet to be studied in detail, this article will serve as a valuable reference.


2014 ◽  
Vol 575 ◽  
pp. 121-127
Author(s):  
Shinn Liang Chang ◽  
Dai Jia Juan ◽  
Bean Yin Lee ◽  
You Jhih Lin

Grinding technology is used in this study to overcome the hard machining of ceramic with hard and brittle characteristics. The grinding machine with diamond grain size 25 and 5 , spindles speed 1720 rpm and 3450 rpm are applied. Combining the unintentional roll clamp and the grinding machine, ceramic rods can be ground to the desired size.In the research, surface profilometer is applied to measure the rod surface roughness of processing results under different conditions. The results show that the grinding wheel with finer particle, the roughness of the ground ceramic rod will be better. While the rotation speed of grinding wheel is increased, the surface roughness will have the same trend.


2009 ◽  
Vol 626-627 ◽  
pp. 159-164 ◽  
Author(s):  
Chang He Li ◽  
Ya Li Hou ◽  
Yu Cheng Ding ◽  
Bing Heng Lu

In the grinding process, grinding fluid is delivered for the purposes of chip flushing, cooling, lubrication and chemical protection of work surface. Due to high speed rotating grinding wheel, the boundary layer of air around the grinding wheel restricts most of the grinding fluid away from the grinding zone. Hence, conventional method of delivering grinding fluid that flood delivery is not believed to fully penetrate this boundary layer and, thus, the majority of the grinding fluid is deflected away from the grinding zone. The flood grinding typically delivers large volumes of grinding fluid was ineffective, especially under high speed grinding conditions. In the paper, a theoretical model is presented for flow of grinding fluid through the grinding zone. The model shows that the flow rate through the contact zone between the wheel and the work surface depends on wheel porosity and wheel speed as well as depends on nozzle volumetric flow rate and fluid jet velocity. Furthermore, the model was tested by a surface grinding machine in order to correlate between experiment and theory. Consequently, the effective flow-rate model was found to give a good description of the experimental results and the model can well forecast the effective flow-rate in flood delivery grinding.


Author(s):  
Deepak Pal ◽  
Ajay Bangar ◽  
Rajan Sharma ◽  
Ashish Yadav

Cylindrical grinding is one of the important metal cutting processes used extensively in the finishing operations. Surface finish is the important output responses in the production with respect to quantity and quality respectively. The Experiments are conducted on universal tool and cutter grinding machine with L9 Orthogonal array with input machining variables as work speed, grinding wheel grades and hardness of material. The developed model can be used by the different manufacturing firms to select right combination of machining parameters to achieve an optimal surface roughness (Ra).The results reveals surface roughness (Ra).The predicted optimal values for Ra for Cylindrical grinding process is 1.07 Ra respectively. The results are further confirmed by conducting confirmation experiments.


2021 ◽  
Vol 60 (1) ◽  
pp. 691-701
Author(s):  
Zhibo Yang ◽  
Wang Sun ◽  
Dongyu He ◽  
Daocheng Han ◽  
Wei Wang ◽  
...  

Abstract In this article, the laser-assisted ultrasonic vibration dressing technique was applied to the cubic boron nitride (CBN) grinding wheel to study the effect of various process parameters (namely, laser power, dressing depth, feed rate, and grinding wheel speed) on the grinding force, surface quality, and morphological evolution of CBN abrasive particles. The results showed that abrasive particles’ morphology mainly undergoes micro-crushing, local crushing, large-area crushing, macro-crushing, and other morphological changes. The dressing force can be effectively reduced by controlling the dressing process parameters. Besides, grinding tests are performed on the grinding wheel after dressing to reveal specimens’ surface quality. Excellent grinding characteristics and grinding quality of the grinding wheel were obtained by the proposed technique with the optimized process parameters.


2018 ◽  
Vol 249 ◽  
pp. 03003 ◽  
Author(s):  
M A Aulestia Viera ◽  
F A Alexandre ◽  
P R Aguiar ◽  
R B Silva ◽  
E C Bianchi

The study and monitoring of the workpiece surface roughness is one of the most important parameters of the grinding process. This paper proposes a method for analysing the surface condition of ground ceramic components by means of the acoustic emission (AE) signal analysis along with frequency domain techniques. Tests were performed using a surface-grinding machine equipped with a resin-bond diamond grinding wheel, where signals were collected at 2 MHz. Alumina workpieces were machined under six different depth of cut values, covering slight, medium and severe grinding conditions. Frequency content was studied in order to select bands closely related to the process conditions. An analysis of the root mean square values (RMS) of the signals was performed, seeking for a correlation with the surface roughness. Digital filters were applied to the raw signals. The RMS values filtered for two frequency bands presented a better fitting to the linear regression, which is highly desirable for setting a threshold to detect the workpiece surface conditions and implementing into a monitoring system. Results showed that the amplitude of the signals presented different characteristics in the frequency domain according to the workpiece surface condition. It was also observed a higher spectral activity in the severe grinding conditions.


2013 ◽  
Vol 797 ◽  
pp. 234-239 ◽  
Author(s):  
Li Fei Liu ◽  
Fei Hu Zhang ◽  
Chun Hui Li ◽  
Jiang Chen ◽  
Min Hui Liu

In this paper, experiments are conducted to study the characters of Ultrasonic Assisted Grinding (UAG) and Conventional Grinding (CG), diamond grinding wheel is used in experiments, grinding forces and surface roughness are measured in both UAG and CG. The effects of different parameters on grinding force, surface roughness and force ratio are discussed. The results show that the grinding force and surface roughness in UAG is smaller than those in CG. The force ratio in UAG is lower than that in CG, which reveals that the grinding wheel has a good wear-resistant property in UAG process.


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