scholarly journals Edge Grinding Characteristics of Display Glass Substrate

2021 ◽  
Vol 5 (1) ◽  
pp. 20
Author(s):  
Dennis Wee Keong Neo ◽  
Kui Liu ◽  
Rui Huang ◽  
Hu Wu
Keyword(s):  
Glass Substrate ◽  
Experimental Studies ◽  
Vertical Direction ◽  
Grinding Force ◽  
High Wear Resistance ◽  
Grinding Wheel ◽  
Experimental Conditions ◽  
Diamond Grit ◽  
Good Thermal Stability ◽  
Glass Edge

Display glass substrate as a brittle material is very challenging to machine due to its excellent physical, mechanical, electrical, and optical properties such as high hardness, high strength, high wear resistance, good fracture toughness, good chemical stability, and good thermal stability. On the basis of Griffith fracture mechanics, our theoretical analysis indicated that edge grinding of the display glass substrate is under brittle mode when grinding with the given conditions, which was verified by the experimental studies of ground glass edge surface topography and fractured surface obtained. Grinding force (Fy) in the vertical direction was much larger than grinding force (Fx) in the horizontal direction, causing a large compressive stress acting on the grinding glass edge. Grinding torque was slightly increased with the increase of grinding speed. Grinding temperature was very high when measured under dry grinding compared with measurement under high-pressure coolant. Grinding of glass substrate edge was performed partially under ductile mode machining in the experimental conditions, which can be attributed to and contributed by those micro cutting edges generated by the fractured diamond grit on the grinding wheel surface.

scholarly journals An Improved Cutting Force Model for Ultrasonically Assisted Grinding of Hard and Brittle Materials

2021 ◽  
Vol 11 (9) ◽  
pp. 3888
Author(s):  
Renke Kang ◽  
Jinting Liu ◽  
Zhigang Dong ◽  
Feifei Zheng ◽  
Yan Bao ◽  
...  
Keyword(s):  
Cutting Force ◽  
Cutting Forces ◽  
Experimental Studies ◽  
Brittle Materials ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Force Model ◽  
Cutting Force Model ◽  
Fillet Radius ◽  
Hard And Brittle Materials

Cutting force is one of the most important factors in the ultrasonically assisted grinding (UAG) of hard and brittle materials. Many theoretical and experimental studies show that UAG can effectively reduce cutting forces. The existing models for UAG mostly assume an ideal grinding wheel with abrasives in both the end and lateral faces to accomplish material removal, whereas the important role of the transition fillet surface is ignored. In this study, a theoretical cutting force model is presented to predict cutting forces with the consideration of the diamond abrasives in the end face, the lateral face, and the transition fillet surface of the grinding tool. This study analyzed and calculated the vibration amplitudes and the cutting forces in both the normal and tangential directions. It discusses the influences of the input parameters (rotation speed, feed rate, amplitude, depth and radius of transition fillet) on cutting forces. The study demonstrates that the fillet radius is an important factor affecting the grinding force. With an increase in fillet radius from 0.2 to 1.2 mm, the grinding force increases by 139.6% in the axial direction and decreases by 70% in the feed direction. The error of the proposed cutting force model is 10.3%, and the experimental results verify the correctness of the force model.

Experimental Studies of Pressure Loss for Large Particle Slurry Transport in Oscillated Pipe for Subsea Mining

2017 ◽  
Author(s):  
Satoru Takano ◽  
Sotaro Masanobu ◽  
Shigeo Kanada ◽  
Masao Ono ◽  
Motoki Araki ◽  
...  
Keyword(s):  
Flow Rate ◽  
Pressure Loss ◽  
Large Particle ◽  
Experimental Studies ◽  
Vertical Direction ◽  
Solid Particles ◽  
Experimental Conditions ◽  
Scaled Model ◽  
Riser Pipe ◽  
Slurry Transport

Subsea minerals exist in the deep water within Japanese exclusive economic zone. Development of slurry pump passing large particles is required for lifting ore. In design of slurry pump, it is significant to estimate the pressure loss in a riser pipe for large particle slurry transport. Therefore the authors have been studied the slurry flow model for large particle slurry transport. In addition, the authors developed the model for the static pipe including the inclined configurations. Since the lifting pipe will be oscillated due to the connected ship motion and VIV (Vortex Induced Vibration), the authors conducted the scaled model experiment to investigate the effects of pipe oscillation on the pressure loss. The model scale was 1/8. Alumina beads and glass beads were used as solid particles in the experiment. The pipe was vertical, and oscillated in horizontal or vertical direction. The experimental results showed that the horizontal and vertical oscillation had little influence on the static pressure loss in most of the experimental conditions. However the influence was observed for the horizontally oscillating pipe in the low slurry velocity and short oscillation period condition. On the other hand, the significant fluctuation components of pressure loss and flow rate were observed in vertically oscillating pipe. The results also indicated that the density of slurry and amplitude of oscillation had influence on the fluctuation components of pressure loss and flow rate but the particle diameters had little influence on them.

Experimental Studies on Grinding of Titanium Alloy with SG Wheels

2007 ◽  
Vol 329 ◽  
pp. 75-80 ◽  
Author(s):  
H.X. Zhang ◽  
Wu Yi Chen ◽  
Z.T. Chen
Keyword(s):  
Titanium Alloy ◽  
Experimental Studies ◽  
Dimensional Accuracy ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Wheel Wear ◽  
Grinding Wheel Wear ◽  
Conventional Grinding ◽  
Abrasive Tools

The grinding process has been investigated in the machining of titanium alloy with conventional grinding wheel and SG grinding wheel respectively. The machinability discussed here includes grinding force, surface roughness, dimensional accuracy, grinding ratio, grinding-wheel wear and grinding-wheel life. The SG grinding wheel is found to possess particularly good grinding properties and is more suitable for grinding titanium alloy when compared with conventional abrasive tools.

Analysis of the Grinding Characteristics of β-Ga2O3 Crystal on Different Planes

2020 ◽  
Vol 19 (02) ◽  
pp. 235-248
Author(s):  
Hai Zhou ◽  
Jiahui Wei ◽  
Fang Song ◽  
Yongkang Li ◽  
Chuanjin Huang ◽  
...  
Keyword(s):  
Specific Energy ◽  
Grinding Force ◽  
Surface Grinding ◽  
Grinding Wheel ◽  
Experimental Conditions ◽  
Grinding Force Ratio ◽  
Force Ratio ◽  
Grinding Conditions ◽  
Grinding Machine

The (010) and (100) planes of a [Formula: see text]-Ga2O3 crystal were subjected to precision grinding tests with a resin bond diamond grinding wheel on a precision surface grinding machine. The grinding characteristics and surface grinding quality of the planes of the [Formula: see text]-Ga2O3 crystal were analyzed on the basis of grinding force, grinding force ratio, specific energy, and surface morphology. The (010) plane shows a larger grinding force and specific energy but a smaller grinding force ratio compared with the (100) plane. Under experimental conditions, the normal and tangential grinding forces of the (010) plane are 1.4–2.2 and 2.6–7.8 times that of the (100) plane, respectively. The specific energy of the (010) plane is 2.8–6.1 times that of the (100) plane, and the grinding force ratio of the (100) plane is 1.4–3.7 times that of the (010) plane. Under the same grinding conditions, the material removal methods for the two planes are evidently different. The (010) plane is mainly removed by brittle fracture and accompanied by a minimal broken area, whereas the (100) plane is mainly removed by cleavage layering and exhibits numerous block cleavage. The (100) plane is the strong cleavage surface, and the (100) plane demonstrates a higher surface roughness than the (010) plane under the same grinding conditions.

scholarly journals Study on the Effect of Grinding Pressure on Material Removal Behavior Performed on a Self-Designed Passive Grinding Simulator

2021 ◽  
Vol 11 (9) ◽  
pp. 4128
Author(s):  
Peng-Zhan Liu ◽  
Wen-Jun Zou ◽  
Jin Peng ◽  
Xu-Dong Song ◽  
Fu-Ren Xiao
Keyword(s):  
Residual Stress ◽  
Surface Roughness ◽  
Service Life ◽  
Material Removal ◽  
Removal Rate ◽  
Grinding Force ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Grinding Temperature ◽  
Grinding Efficiency

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.

scholarly journals Temperature uniformity in the CERN CLOUD chamber

2017 ◽  
Vol 10 (12) ◽  
pp. 5075-5088 ◽  
Author(s):  
António Dias ◽  
Sebastian Ehrhart ◽  
Alexander Vogel ◽  
Christina Williamson ◽  
João Almeida ◽  
...  
Keyword(s):  
Steady State ◽  
Air Temperature ◽  
Elevated Temperatures ◽  
Trace Gases ◽  
Vertical Direction ◽  
Cloud Chamber ◽  
Temperature Uniformity ◽  
Atmospheric Conditions ◽  
Cloud Droplets ◽  
Experimental Conditions

Abstract. The CLOUD (Cosmics Leaving OUtdoor Droplets) experiment at CERN (European Council for Nuclear Research) investigates the nucleation and growth of aerosol particles under atmospheric conditions and their activation into cloud droplets. A key feature of the CLOUD experiment is precise control of the experimental parameters. Temperature uniformity and stability in the chamber are important since many of the processes under study are sensitive to temperature and also to contaminants that can be released from the stainless steel walls by upward temperature fluctuations. The air enclosed within the 26 m3 CLOUD chamber is equipped with several arrays (strings) of high precision, fast-response thermometers to measure its temperature. Here we present a study of the air temperature uniformity inside the CLOUD chamber under various experimental conditions. Measurements were performed under calibration conditions and run conditions, which are distinguished by the flow rate of fresh air and trace gases entering the chamber at 20 and up to 210 L min−1, respectively. During steady-state calibration runs between −70 and +20 °C, the air temperature uniformity is better than ±0.06 °C in the radial direction and ±0.1 °C in the vertical direction. Larger non-uniformities are present during experimental runs, depending on the temperature control of the make-up air and trace gases (since some trace gases require elevated temperatures until injection into the chamber). The temperature stability is ±0.04 °C over periods of several hours during either calibration or steady-state run conditions. During rapid adiabatic expansions to activate cloud droplets and ice particles, the chamber walls are up to 10 °C warmer than the enclosed air. This results in temperature differences of ±1.5 °C in the vertical direction and ±1 °C in the horizontal direction, while the air returns to its equilibrium temperature with a time constant of about 200 s.

scholarly journals Experimental Study on Grinding Force of Zirconia Ceramics in Dry/Wet Grinding Environment

2018 ◽  
Vol 198 ◽  
pp. 02004
Author(s):  
Junping Zhang ◽  
Weidong Wang ◽  
Songhua Li ◽  
Han Tao
Keyword(s):  
Grinding Force ◽  
Grinding Wheel ◽  
Feed Speed ◽  
Zirconia Ceramics ◽  
Grinding Forces ◽  
Measuring Device ◽  
Linear Speed ◽  
Wet Grinding ◽  
Dry Grinding ◽  
Force Ratio

The impacts of different linear speed of grinding wheel, grinding depth and workpiece feed speed with or without grinding fluid on grinding force were studied by plane grinding machining of zirconia ceramics. The impacts of different machining environment and grinding parameter on normal and tangential grinding forceswere studied by testing the grinding force during grinding with a force measuring device. The studies showed that the normal and tangential grinding forces decrease with the increase of the linear speed of grinding wheel and increase with the improvement of grinding depth and workpiece feed speed. The grinding depth has the greatest impacts on the normal and tangential grinding forces in dry grinding environment; while in wet grinding environment, the grinding depth exerts the greatest impacts on the normal grinding force and the linear speed of grinding wheel imposes the greatest impacts on the tangential grinding force. In addition, it was found that the normal grinding force in dry grinding is minor than that in wet grinding, that the tangential grinding force in dry grinding is greater than that in wet grinding, and that the grinding force ratio in dry grinding is lower than that in wet grinding.

scholarly journals Mechanism of the process of decomposition of apatitis with phosphoric acid

2019 ◽  
Vol 81 (1) ◽  
pp. 294-297
Author(s):  
R. F. Sabirov ◽  
A. F. Makhotkin ◽  
Yu. N. Sakharov ◽  
I. A. Makhotkin ◽  
I. Yu. Sakharov
Keyword(s):  
Phosphoric Acid ◽  
Ph Value ◽  
Batch Reactor ◽  
Experimental Studies ◽  
Hydrogen Ions ◽  
Experimental Conditions ◽  
Monocalcium Phosphate ◽  
Ph Values ◽  
Whole Process ◽  
Proportional Increase

Experimental studies of the kinetics and mechanism of the process, decomposition of apatite by phosphoric acid, in the Apatite-H3PO4-H2O system without the addition of sulfuric acid have been performed. The study of the decomposition process of Kovdorsky apatite with certain particle sizes was carried out in a batch reactor with a volume of 1 dm3 with stirring of the reaction mixture, and an initial concentration of phosphoric acid of 17% by weight, at a temperature of 78–82 °C. Observation of the process was carried out by determining the concentration of phosphoric acid and the concentration of monocalcium phosphate. The acidity of the reaction mixture was determined by the pH meter readings (pH-105 MA with a glass combined-ESC-10603 electrode). It was shown that during the whole process a constant smooth increase in the pH value of the reaction mixture to pH 6 occurs. Comparison of the pH values of the reaction mixture during the actual at the time of determining the concentration of phosphoric acid and pH of phosphoric acid of the corresponding concentration in the aqueous solution shows that the pH value of the reaction mixture is significantly affected by the presence of monocalcium phosphate gel. During the process, during the first thirty minutes, the concentration of phosphoric acid decreases from 17 to 10% by weight, the corresponding quantitative formation of monocalcium phosphate gel and a proportional increase in the pH of the reaction mixture. Then, as the concentration of phosphoric acid decreases, the process slows down and does not proceed to the end under the experimental conditions. The dependence of the concentration of hydrogen ions in the reaction mixture on the time of the process of decomposition of apatite in phosphoric acid, which is presented in logarithmic coordinates, shows that the mechanism of formation of hydrogen ions during the whole process does not change. Thus, it is shown that the process of decomposition of apatite by phosphoric acid in the Apatite-H3PO4-H2O system proceeds with the formation of an intermediate product - monocalcium phosphate gel. When this occurs, a corresponding significant change in the pH values of the reaction mixture occurs. During the whole process there is a constant decrease in the concentration of phosphoric acid.

scholarly journals ADSORPTION OF PHOSPHATE IONS ON RED SLUDGE

2017 ◽  
Vol 60 (8) ◽  
pp. 80
Author(s):  
Svetlana M. Kramer ◽  
Mariya V. Terekhova ◽  
Inna V. Artamonova
Keyword(s):  
Hydrochloric Acid ◽  
Experimental Studies ◽  
Aluminum Production ◽  
Quantitative Composition ◽  
Experimental Conditions ◽  
Initial Concentration ◽  
Phosphate Ions ◽  
Frumkin’S Isotherm ◽  
Ph Range ◽  
Red Sludge

In work the possibility of red sludge (waste of aluminum production by Bayer's method) to adsorb phosphate ions from water solutions at various concentration of ions and in the pH range from 3 to 10 is studied. Relevance of use of red sludge for receiving on its basis of sorbents is reasoned. For identification of the studied object the qualitative and quantitative composition of red sludge was established by the method of the X-ray phase analysis. The technique of red slage activation by hydrochloric acid, and also an adsorption technique of phosphate ions on the red sludge surface is described. Experimental studies of adsorption of phosphate ions on the surface of the red slage activated by hydrochloric acid depending on рН and concentration of initial solution were conducted. The dependence of adsorption phosphate ions on the red slage activated by НСl on рН and on the initial concentration of phosphate ions in solution is presented. These dependences of a relative fraction of distribution of various ions of phosphoric acid on рН are given in work. The form of ion phosphate having the greatest adsorptive activity on the red slage activated by hydrochloric acid in experimental conditions is revealed. Experimental data on dependence of adsorption of phosphate ions on their initial concentration in solution are described by Frumkin's isotherm. The constant of the adsorptive balance, limit adsorption, the parameter of intermolecular interaction of the adsorbed particles are calculated. Optimum conditions for adsorption of phosphate ions on red slage are established.Forcitation:Kramer S.M., Terekhova M.V., Artamonova I.V. Adsorption of phosphate ions on red sludge. Izv. Vyssh. Uchebn. Zaved. Khim. Khim. Tekhnol. 2017. V. 60. N 8. P. 80-83.

Nonlinear Dynamics of Orthogonal Metal Cutting: Experimental Studies

1999 ◽  
Author(s):  
Chee-Hoe Foong ◽  
Marian Wiercigroch ◽  
William F. Deans
Keyword(s):  
Nonlinear Dynamics ◽  
Cast Iron ◽  
Metal Cutting ◽  
Thrust Force ◽  
Experimental Studies ◽  
Vertical Direction ◽  
Systematic Analysis ◽  
Orthogonal Metal Cutting ◽  
Time Histories ◽  
Force Components

Abstract The elimination of chatter is one of the major aims in machining to improve geometrical accuracy and surface finish. In this study, occurrence of chatter was investigated experimentally using a specially designed rig by examining time histories of the cutting and thrust force components. A broad experimental study was conducted using brass, cast iron and aluminium samples. It was found that by changing the horizontal stiffness of the rig, the thrust force variations (in the vertical direction) were completely eliminated for the cast iron samples. A systematic analysis of the chip formation for the aluminium alloy is presented.

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