scholarly journals Waterjet Erosion Model for Rock-Like Material Considering Properties of Abrasive and Target Materials

2019 ◽  
Vol 9 (20) ◽  
pp. 4234 ◽  
Author(s):  
Cha ◽  
Oh ◽  
Cho
Keyword(s):  
Kinetic Energy ◽  
Material Properties ◽  
Abrasive Particle ◽  
Suggested Model ◽  
Good Qualitative Agreement ◽  
Erosion Model ◽  
Abrasive Particles ◽  
Acceleration Model ◽  
Abrasive Erosion ◽  
Material Erosion

In this study, we investigated the characteristics of abrasive erosion considering the material properties of abrasives and targets. An abrasive particle erosion model considering energy transfer due to hardness differences was developed based on energy conservation using the correlation between volume removal and effective kinetic energy. To obtain the effective erosion kinetic energy of an abrasive, an acceleration model was derived for the abrasive particles, including terms describing the properties of the abrasive and fluid. The applicability of the suggested model was verified by comparing the brittle erosion results obtained using a previous theoretical approach to those of the present numerical analysis. The results obtained using the developed model exhibited good qualitative agreement with the brittle material erosion results. By evaluating acceleration and the erosion characteristics of an abrasive, the erosion performance could be predicted and optimized.

scholarly journals The Surface Condition of Ni-Cr after SiC Abrasive Blasting for Applications in Ceramic Restorations

Materials ◽  
2020 ◽  
Vol 13 (24) ◽  
pp. 5824
Author(s):  
Weronika Czepułkowska-Pawlak ◽  
Emilia Wołowiec-Korecka ◽  
Leszek Klimek
Keyword(s):  
Surface Condition ◽  
Abrasive Particle ◽  
Surface Profile ◽  
Abrasive Particles ◽  
Dental Restorations ◽  
Large Width ◽  
Ceramic Restorations ◽  
The Impact ◽  
Abrasive Size ◽  
Abrasive Blasting

Abrasive blasting is a process widely used in dentistry. One of the uses is the development of metal surfaces for connections with ceramics in fixed prosthetic restorations. The purpose of this paper was to check how the rough surface profile (width, height, and depth on unevenness) impacts the surface’s condition, like its wettability and percentage of stuck abrasives. The Ni-Cr alloy surface was abrasive blasted by silicon carbide with the various pressure parameters (0.2, 0.4, and 0.6 MPa) and abrasive particle sizes (50, 110, and 250 µm). Cleaned surfaces were examined for roughness, wettability, and percentage of stuck abrasive particles on the surface. The surface after abrasive blasting using 110 µm of abrasive size and 0.4 MPa pressure has the best wettability results. The width of unevenness may cause it. When the unevenness has too small or too large width and depth, the fluids may not cover the entire cavities because of locking the air. The surface condition of dental alloys directly affects metal–ceramic connection strength. The knowledge about the impact of the abrasive blasting parameters on the bond strength will allow one to create durable dental restorations.

Material Removal and Application by Chemical Impact Reaction in Nano-Abrasive Jet Polishing

2013 ◽  
Vol 631-632 ◽  
pp. 550-555
Author(s):  
Wen Qiang Peng ◽  
Sheng Yi Li ◽  
Chao Liang Guan ◽  
Xin Min Shen
Keyword(s):  
Material Removal ◽  
Abrasive Particle ◽  
Precision Machining ◽  
Optical Surface ◽  
Polishing Process ◽  
Abrasive Particles ◽  
Mechanical Process ◽  
Abrasive Jet Polishing ◽  
Ultra Precision ◽  
Machining Properties

Material removed by mechanical process inevitably causes surface or subsurface damage containing cracks, plastic scratch, residual stress or dislocations. In nano-abrasive jet polishing (NAJP) the material is removed by chemical impact reaction. The chemical impact reaction is validated by contrast experiment with traditional lap polishing process in which the material is mainly removed through mechanical process. Experiment results show the dependence of the abrasive particles on the choice of materials. Even if the abrasive particle and the workpiece are composed of similar components, the machining properties are remarkably different due to slight differences in their physical properties or crystallography etc. Plastic scratches on the sample which was polished by the traditional mechanical process are completely removed by NAJP process, and the surface root-square-mean roughness has decreased from 1.403nm to 0.611nm. The NAJP process will become a promising method for ultra precision machining method for ultrasmooth optical surface.

scholarly journals Annular Surface Micromachining of Titanium Tubes Using a Magnetorheological Polishing Technique

Micromachines ◽  
2020 ◽  
Vol 11 (3) ◽  
pp. 314 ◽  
Author(s):  
Wanli Song ◽  
Zhen Peng ◽  
Peifan Li ◽  
Pei Shi ◽  
Seung-Bok Choi
Keyword(s):  
Magnetic Field ◽  
Surface Roughness ◽  
Field Strength ◽  
Magnetic Field Strength ◽  
Rotation Speed ◽  
Abrasive Particle ◽  
Internal Surface ◽  
Abrasive Particles ◽  
High Magnetic Field Strength ◽  
Titanium Alloy Tube

In this study, a novel magnetorheological (MR) polishing device under a compound magnetic field is designed to achieve microlevel polishing of the titanium tubes. The polishing process is realized by combining the rotation motion of the tube and the reciprocating linear motion of the polishing head. Two types of excitation equipment for generating an appropriate compound magnetic field are outlined. A series of experiments are conducted to systematically investigate the effect of compound magnetic field strength, rotation speed, and type and concentration of abrasive particles on the polishing performance delivered by the designed device. The experiments were carried out through controlling variables. Before and after the experiment, the surface roughness in the polished area of the workpiece is measured, and the influence of the independent variable on the polishing effect is judged by a changing rule of surface roughness so as to obtain a better parameter about compound magnetic field strength, concentration of abrasive particles, etc. It is shown from experimental results that diamond abrasive particles are appropriate for fine finishing the internal surface of the titanium-alloy tube. It is also identified that the polishing performance is excellent at high magnetic field strength, fast rotation speed, and high abrasive-particle concentration.

scholarly journals Investigation of the Design and Fault Prediction Method for an Abrasive Particle Sensor Used in Wind Turbine Gearbox

Energies ◽  
2020 ◽  
Vol 13 (2) ◽  
pp. 365
Author(s):  
Le Zhang ◽  
Qiang Yang
Keyword(s):  
Wind Turbine ◽  
Design Method ◽  
Abrasive Particle ◽  
Prediction Method ◽  
Fault Prediction ◽  
Superior Performance ◽  
Lubricating Oil ◽  
Operation Performance ◽  
Wind Turbine Gearbox ◽  
Abrasive Particles

The gearbox is a key sub-component of a wind power generation system with high failure rate leading to shutdowns. By monitoring the abrasive particles in the lubricating oil when the gearbox is running, any abnormal condition of the gearbox can be found in advance. This information may be used to improve the operational safety of the wind turbine and reduce losses because of shutdowns and maintenance. In this paper, a three-coil induction abrasive particle sensor is designed based on the application of high-power wind turbine gearbox. The performance of the sensor and the design method of the detection circuit are described in detail, and the sensor operation performance used in the 2 MW wind turbine is verified. The results show that the sensor has superior performance in identifying ferromagnetic abrasive particles above 200 μm and plays a good role in status monitoring and fault prediction for the gearbox.

Wear of Abrasive Particles in Slurry During Lapping

2014 ◽  
Author(s):  
James T. Lehner ◽  
Christopher A. Brown
Keyword(s):  
Particle Size ◽  
Stainless Steel ◽  
Design Of Experiments ◽  
Abrasive Particle ◽  
Steel Ball ◽  
Abrasive Particles ◽  
Individual Variable ◽  
Stainless Steel Ball ◽  
Experimental Runs

Changes in abrasive particle size, shape, and sharpness are studied in multi-axis lapping of sealing regions of stainless steel ball valves. Twelve experimental runs, investigating changes in the abrasive particle as a function of lapping load and motion, are performed during lapping. The influence of changes in the lapping load and motion are investigated using design of experiments. Changes in the size, shape, and sharpness of the abrasive particle are influenced by the load and by the motion of the seats and balls of the valves. Combinations of lapping load and motions, as opposed to any individual variable, tend to dominate the influence on the changes in the abrasive particle.

Vibration Polishing Edge Preparation for Cemented Carbide Inserts

2012 ◽  
Vol 201-202 ◽  
pp. 1174-1177
Author(s):  
Jiao Wang ◽  
Hao Wang ◽  
Ai Bing Yu
Keyword(s):  
Cutting Tools ◽  
Abrasive Particle ◽  
Optical Microscope ◽  
Cutting Edge ◽  
Cemented Carbide ◽  
Abrasive Particles ◽  
Cemented Carbide Tool ◽  
Carbide Inserts ◽  
Edge Preparation ◽  
Cemented Carbide Inserts

Micro-cracks on cutting edge will cause early breakages on cutting tools, accelerate tool wear and reduce cemented carbide tool life. Edge preparation can improve the cutting edge quality. Vibration polishing experiments were carried out for cemented carbide inserts edge preparation. Inserts and fixtures were put into the vibration polishing equipment which forced abrasive particles to collide and polish inserts. Edge preparation for fixed type insert and free type insert were compared with three sizes of abrasive particles. And the polishing time was changed for each testing cases. Experiments were carried out by altering polishing time, abrasive particle size and tool clamping way to determine the optimum technology of vibration polishing edge preparation. The experimental results showed that edge breakage numbers of insert significantly reduced. Smooth and round cutting edges were observed by optical microscope after edge preparation. Edge preparation experiments prove that edge preparation can change the cutting edge geometry and improve the cutting tool quality.

Surface re-orientation caused on metals by abrasion—its nature, origin and relation to friction and wear

1958 ◽  
Vol 247 (1250) ◽  
pp. 353-368 ◽  
Keyword(s):  
Fibre Orientation ◽  
Normal Load ◽  
Abrasive Particle ◽  
Electron Diffraction Investigation ◽  
Abrasive Particles ◽  
Emery Paper ◽  
Axis Parallel ◽  
First Time ◽  
Rotational Slip ◽  
Increasing Load

No adequate study of the surface structure of abraded poly crystalline metals has been made hitherto. The present electron-diffraction investigation of unidirectionally abraded beryllium and magnesium elucidates for the first time the characteristic nature and the origin of the fibre texture caused by abrasion, particularly its relation to the friction coefficient and the wear. The effects of a wide variety of conditions of load, speed, temperature and abrasive-particle size are determined. The main fibre orientation developed is of [001] type, the axis being inclined by an angle δ away from the outward normal, towards the direction from which the abrasive particles came. For beryllium δ is about 21°, the fibre axis being then along the resultant of the normal load W and the tangential frictional force F , at tan-1 μ = tan -1 0.38 to the normal. For magnesium δ= 22° and μ = 0*40. This main oblique fibre orientation is clearly a compres­sion texture, the (0001) slip lamellae becoming oriented normal to the compression axis. A very weak tendency of azimuthal preference round this axis, with <100> normal to the abrasion direction, was also observed in a few cases. With increasing load (above 1 Kg/cm 2 , using 0000 emery paper) on beryllium, in addition to the above main oblique texture the surface regions showed an increasing proportion of metal having a [001] fibre orientation with its axis normal to the surface, associated with the progressively greater amount of metal removed by shearing. Similar oblique and normal [001] fibre textures are developed by abrasion on single-crystal beryllium surfaces, showing clearly the extent of the lattice fragmentation. The region of transition to the underlying undisturbed crystal lattice indicates by its form that the deformation process involves flexural rotational slip on (0001), i. e. rotational slip on (0001) with simultaneous flexure of the slip lamellae about an axis parallel to (0001) not limited to the usual <210> direction.

Research of the Dynamic Abrasive Particles Field

2009 ◽  
Vol 407-408 ◽  
pp. 569-572
Author(s):  
Shi Ming Ji ◽  
Ya Qi Shen ◽  
Li Zhang ◽  
Ming Sheng Jin ◽  
Yin Dong Zhang
Keyword(s):  
Image Processing ◽  
High Speed ◽  
Abrasive Particle ◽  
Critical Study ◽  
Abrasive Particles ◽  
Particle Field ◽  
Surface Polishing ◽  
Working Surface ◽  
Motion State ◽  
Dynamic Form

In this paper, a critical study into the dynamic form of abrasive particles through polishing are made, which are under “inconsistent curvature contact” status. In this system, some abrasive particles are colored up and mixed with ordinary ones, by utilizing transparent working surface and stroboscopic light as well; motion state of abrasive particles can be photographed by high speed shot technology. This method can get serials of images while polishing. By using digital image processing technology, distribution of abrasive particle field can be obtained finally. In this paper, the abrasive particles field is researched to obtain the perfect abrasive particle field after purposefully control. Then the influence of the removed material caused by abrasive particles field can be improved, so it can provide strong theory foundation and practice guidance to surface polishing practice.

Studies of Micro-Hole Burr Improvement for Aluminum Alloy Materials Using Vibrated Abrasive Grinding Machining

2015 ◽  
Vol 642 ◽  
pp. 202-206 ◽  
Author(s):  
Shie Chen Yang ◽  
Tsuo Fei Mao ◽  
Feng Che Tsai ◽  
Hsi Chuan Huang
Keyword(s):  
Image Processing ◽  
Aluminum Alloy ◽  
Material Properties ◽  
Vertical Direction ◽  
Experimental Results ◽  
Processing Technology ◽  
Vibration Energy ◽  
Abrasive Particles ◽  
Image Processing Technology ◽  
Micro Hole

This study investigated the removal improvement of micro burrs of aluminum alloy materials using vibrated abrasive grinding machining. The image processing technology is used to examine and quantify the micro-hole burr profiles. The experimental results show that the micro burr was uniformly removed as the workpiece is fixture with vertical direction. In addition, the burr removal improvements are effectively influenced by the flowing velocity and the vibration energy of abrasive particles. The flowing velocities are dependent on the size and gravity of the abrasives and the vibration energy is determined by the material properties and the hardness of the abrasives.

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