Grinding Characteristics of Sapphire Using ELID and High Hardness Iron Plating Grinding Wheel

2018 ◽  
Vol 2018 (0) ◽  
pp. YC2018-097
Author(s):  
Kazuki SHIMIZU ◽  
Nobuhide ITOH ◽  
Hitoshi OHMORI ◽  
Takashi MATSUZAWA ◽  
Katsufumi INAZAWA
Keyword(s):  
High Hardness ◽  
Grinding Wheel ◽  
Iron Plating

Effect of Complex Electrodischarge Grinding for Electrically Conductive PCD

2011 ◽  
Vol 325 ◽  
pp. 276-281 ◽  
Author(s):  
Manabu Iwai ◽  
Shinichi Ninomiya ◽  
Kiyoshi Suzuki
Keyword(s):  
High Efficiency ◽  
Low Cost ◽  
Surface Condition ◽  
High Hardness ◽  
Grinding Wheel ◽  
Wheel Wear ◽  
Electrically Conductive ◽  
Grinding Method ◽  
Conventional Grinding ◽  
Composite Diamond

Polycrystalline Composite Diamond (PCD) is excellent in chipping resistance despite its very high hardness. However, it is not easy to EDM or grind PCD. To realize high efficiency and high quality processing of PCD simply and at low cost, the authors devised new PCD (EC-PCD) by using electrically conductive diamond particles and applied a complex electrodischarge grinding method. In this study, investigation is made on effective grinding condition to realize high efficiency, low and stable grinding force and low wheel wear in complex electrodischarge grinding. As a result, superior grinding property was obtained when the grinding wheel was set at minus polarity, and set peak current of iP = 4 and 6 A was applied. Furthermore it also became clear that additional conventional grinding process followed after complex electrodischarge grinding improved the surface condition.

Wear of Diamond Grinding Wheel during Low Speed Dressing by Alumina

2015 ◽  
Vol 658 ◽  
pp. 120-124
Author(s):  
Tachai Luangvaranunt ◽  
Natthawat Tangkaratanakul ◽  
Patchanok Sakultantimetha
Keyword(s):  
High Hardness ◽  
Large Mass ◽  
Diamond Wheel ◽  
Grinding Wheel ◽  
Work Piece ◽  
Wheel Wear ◽  
Diamond Grinding Wheel ◽  
Diamond Grinding ◽  
Dressing Tool ◽  
Pin On Disk

Diamond grinding wheel is used in high precision grinding process, when work piece has a very high hardness. For a specific grinding interval, the wheel must be properly dressed, in order to remove swarf, sharpen the worn diamond grits, open up new diamond protrusions, and recondition the bond material. Dressing of diamond grinding wheel by alumina dressing tool has been simulated in a pin-on-disk machine in the research. Sharpening of the wheel is indicated by the increase of its roughness value, and surface microstructure with protruding sharp diamond grits. It was found that increasing of sliding distant from 100 to 500 m will increase the roughness of the wheel. The increase of contact load from 10 to 20 N will also increase roughness of the wheel, and the severity of wheel wear, indicated by high values of friction coefficient. A proper dressing of this nickel bonded SD1200 diamond wheel is by sliding against alumina dressing tool for at least 300 m under 10 N load. Sliding velocity has minimal effect to the results. A too large sliding distant and load will cause severe damage to wheel surface, and severe wheel wear, indicated by its large mass loss.

Experiment Study on ELID Grinding of TN85 Cermets

2011 ◽  
Vol 175 ◽  
pp. 131-135
Author(s):  
Fu Qiang Tong ◽  
Fei Hu Zhang ◽  
Dian Rong Luan
Keyword(s):  
Metal Matrix ◽  
High Hardness ◽  
Diamond Powder ◽  
Diamond Wheel ◽  
Precision Machining ◽  
Grinding Wheel ◽  
Powder Particle Size ◽  
Matrix Composites ◽  
Elid Grinding ◽  
Ultra Precision

TN85 cermets is one kind of particle reinforced metal matrix composites, which is high hardness, good wear resistance, and bring great difficulties in processing, so it is necessary to study the processing performance. During the test on ELID grinding TN85 cermets, it is found that plastic removal is the main ways during grinding TN85 cermets materials. The powder particle size of W2.5 diamond wheel is successfully used in full removal of TN85 cermets plastic, the surface roughness value of rms: 16.81nm and Ra: 12.52nm. The results showed that: ELID grinding wheel with diamond powder technology can be used in ultra-precision machining TN85 cermets.

Effects of Impregnation of Grinding Wheel on Grinding Hardened Tool Steel

1985 ◽  
Vol 9 (1) ◽  
pp. 39-44 ◽  
Author(s):  
M.A. Younis ◽  
H. Alawi
Keyword(s):  
Structural Changes ◽  
Metal Removal ◽  
Removal Rate ◽  
Ground Surface ◽  
High Hardness ◽  
Grinding Wheel ◽  
Tool Steels ◽  
Wheel Wear ◽  
Beneficial Effects ◽  
Hardened Tool Steel

The high hardness and chemical effects of tool steels M2 and T15 cause a rapid grinding wheel wear and micro structural changes in the ground surface. The performance of sulphur-, wax-, and varnish-impregnated grinding wheels in grinding hardened tool steels M2 and T15 is investigated and compared with the performance of conventional alumina wheels. Impregnation with sulphur had in all cases beneficial effects by decreasing the grinding forces, increasing the maximum metal removal rate, improving surface integrity, and increasing considerably the grinding ratio. It also gave cost saving compared to the plain grinding wheel. The improvement was a result of the sulphur being more efficiently supplied into the chip formation process as compared to using grinding coolant only.

Study of Grinding Wheel for Polishing Diamond by Dynamic Friction Polishing

2014 ◽  
Vol 1017 ◽  
pp. 304-309 ◽  
Author(s):  
Shuang Ji Shi ◽  
Jia Zhi Lin ◽  
Zhu Ji Jin ◽  
Xiao Guang Guo ◽  
Ping Zhou ◽  
...  
Keyword(s):  
Mechanical Property ◽  
Chemical Change ◽  
High Hardness ◽  
Mechanical Effect ◽  
Grinding Wheel ◽  
Dynamic Friction ◽  
Powder Metallurgy Technique ◽  
Innovative Method ◽  
Catalytic Metal ◽  
Synergistic Reaction

Diamond is widely used in the fields of precise and ultraprecise machining because of its superlative characters. Due to high hardness and great brittleness of diamond, the grinding of diamond needs a kind of high effective and stable polishing method. Dynamic friction polishing (DFP) is deemed to be an innovative method by means of a synergistic reaction of mechanical effect and chemical change. The condition of high pressure and high temperature puts forward a high requirement for mechanical property of the grinding wheel in DFP, other than that, the graphitization of diamond catalyzed by catalytic metal is also a focus of research. In this paper, the transition metals with unpaired d electrons were selected as polishing materials, and powder metallurgy technique was used to prepare alloy grinding wheel for polishing diamond by dynamic friction polishing.

Development on Micro Precision Truing Method of ELID-Grinding Wheel (1st Report: Principle & Fundamental Experiments)

2005 ◽  
Vol 291-292 ◽  
pp. 207-212 ◽  
Author(s):  
Hitoshi Ohmori ◽  
Shao Hui Yin ◽  
Wei Min Lin ◽  
Yoshihiro Uehara ◽  
Shinya MORITA ◽  
...  
Keyword(s):  
High Precision ◽  
High Efficiency ◽  
High Hardness ◽  
Experimental Results ◽  
Grinding Wheel ◽  
Grinding Process ◽  
Grinding Wheels ◽  
Elid Grinding ◽  
High Toughness ◽  
Diamond Grinding

Metal bonded diamond grinding wheels are widely used in the grinding process, especial in ELID grinding. However, truing is difficult owing to the high toughness of metal bond materials and high hardness of diamond abrasives. To realize high precision and high-efficiency truing, we propose a new micro-truing method consisting of electro-discharge truing and electrolysis-assisted mechanical truing in this paper. The process principle and fundamental experimental results are introduced, and the truing performance is discussed. Research results show that the proposed new method is effective for truing metal bonded diamond grinding wheels.

Wear Mechanisms in Grinding of PCBN

2016 ◽  
Vol 1136 ◽  
pp. 555-560 ◽  
Author(s):  
Berend Denkena ◽  
Thilo Grove ◽  
Leif Behrens
Keyword(s):  
Wear Mechanism ◽  
High Hardness ◽  
Economic Benefits ◽  
Production Costs ◽  
Grinding Wheel ◽  
End User ◽  
Wheel Wear ◽  
Steel Cast ◽  
High Feed ◽  
High Production

PCBN-inserts have a high potential in the cutting of hardened steel, cast iron and super alloys due to their high hardness and heat resistance. Nevertheless they have a high purchase price, which lowers the economic benefits for the end user compared to other cutting materials. This is caused by the high production costs of the inserts. The grinding of PCBN-inserts causes a major proportion of these costs as a result of the high grinding wheel wear. The primary wear mechanism is grain breakout followed by clogging of the grinding layer. This study shows that the efficiency of the grinding process can be increased significantly by applying low cutting speeds and high feed rates. In this case, splintering of the grinding grain is the main wear mechanism.

Electrode Characteristics of High Pressure Synthetic High Boron Doped Diamond

2006 ◽  
Vol 315-316 ◽  
pp. 507-510 ◽  
Author(s):  
Jian Bing Zang ◽  
Yan Hui Wang ◽  
W. Tang ◽  
H. Huang
Keyword(s):  
High Pressure ◽  
Carbon Sources ◽  
High Hardness ◽  
Diamond Powder ◽  
Grinding Wheel ◽  
Potential Range ◽  
Boron Doped Diamond ◽  
Boron Doped ◽  
High Boron ◽  
Electrode Characteristics

B-doped diamond is an excellent grinding material owing to its high hardness, oxidation resistance and chemical inertness as well as low resistance. The recent developments of Boron doped conductive diamond has further increased the scale of diamond applications including the manufacture of electrically conductive grinding wheel or the use as an electrode in EDM. The unique electrochemical properties also attract the researchers’ attention on the applications of electrode, sensor and detectors etc. This paper presents a viable technology that high boron doped diamond is synthesized under high pressure and high temperature using B-doped GICs as carbon sources. The synthetic diamond grains with electrically resistivity of 2cm are sufficiently conductive for electrochemistry measurement. Cyclic voltammotry was performed to evaluate the electrode characteristics of diamond powder. The results shows that B-doped diamond powder electrode is electrochemically stable in the supporting electrolytes such as 0.1M KCl, 0.5M Na2SO4 and 0.1M H2SO4 over a wide potential range. The level of background current is very low. The electrode reaction is quasi-reversible in 0.5M Na2SO4 containing the ferricyanide-ferrocyanide redox couple.

A Study on Grinding Brittle Material with Pattern-Dressed Wheel

2016 ◽  
Vol 861 ◽  
pp. 14-19
Author(s):  
Pei Lum Tso ◽  
Weng Hong Lin
Keyword(s):  
Contact Area ◽  
Brittle Materials ◽  
High Hardness ◽  
Diamond Wheel ◽  
Depth Of Cut ◽  
Grinding Wheel ◽  
Grinding Wheels ◽  
Specific Grinding Energy ◽  
Diamond Grinding ◽  
Selection Parameters

The high hardness of brittle materials always make it hard to machine with traditional grinding wheels. Conventionally a diamond grinding wheels was used to improve the poor processing capability. Usually the specific grinding energy had been used as an indicator of machinability. According to its definition, the specific grinding energy increases with the active contact area of the grinding wheel decreases. In other words, reducing the surface contact area of the grinding wheel can enhance the specific grinding energy effectively. Conditioning grooves on grinding wheels not only enhance the specific grinding energy, but also achieve the effect of reducing the heat dissipated during the grinding processes. With the proper selection parameters, the high cost of diamond grinding wheel may be replaced by less expensive conventional green carbon and aluminum oxide wheel. In this studies, the relationship between the surface topography of grinding wheels and the grinding capability of brittle materials was investigated. The results show that, the traditional grinding wheel dressing properly while the depth of cut less than 20μm with the rhombic pattern and the depth of cut more than 20μm with the groove-like pattern can grind the brittle materials as good as using diamond wheel.

A Study on Electrolytic In-Process Dressing (ELID) Grinding of Sapphire With Acoustic Emission

2009 ◽  
Author(s):  
Peidong Han ◽  
Ioan D. Marinescu ◽  
Anil Srivastava
Keyword(s):  
Acoustic Emission ◽  
Surface Finish ◽  
High Efficiency ◽  
High Hardness ◽  
Processing Parameters ◽  
Great Promise ◽  
Grinding Wheel ◽  
Wheel Wear ◽  
Elid Grinding ◽  
Wheel Loading

Single crystal sapphire is of significant interest due to its combination of excellent optical, electrical, and mechanical properties. However, fine grinding of sapphire is quite challenging because of its high hardness and low fracture toughness, making it sensitive to cracking. Wheel loading is a common problem in conventional grinding of hard and brittle materials. ELID grinding shows great promise in achieving a mirror surface finish at a relatively high efficiency. ELID grinding of sapphire was investigated using acoustic emission. The effects of processing parameters on surface finish and acoustic emission signals were evaluated. Correlations were found among the dressing current intensity, surface finish and acoustic emission signals. A smoother surface was obtained using a higher dressing current at the cost of a higher wheel wear rate. The wheel wear mechanism in ELID grinding of sapphire was dominated by bond fracture because the bond strength is reduced by electrolysis. Results indicate that the acoustic emission technique has the potential to be used for monitoring ELID grinding process, detecting the condition of the grinding wheel, and investigating the mechanisms of ELID grinding.

Sign in / Sign up

Export Citation Format

Share Document