金刚石与磨料磨具工程

Impact of grinding speed and pressure on material removal characteristics of monocrystalline silicon

YU Yuebin, WANG Ziguang, ZHOU Ping, GAO Shang, GUO Dongming

2016, 36(3): 1-5,10. doi: 10.13394/j.cnki.jgszz.2016.3.0001

Abstract(336)

PDF 2149KB(27)

Abstract:
In order to study the damage of monocrystalline silicon,it is ground using a diamond grinding block at different normal forces and velocities.The grain size of resin bond diamond grinding block is 38 to 45 μm.The surface roughness value R_a,subsurface damage depth d_sd and material removal rate MMR of monocrystalline silicon are measured to study the effect of grinding velocity and pressure on material removal quality.Resultsshow that the material removal rate of monocrystalline silicon firstly increases and then decreases with the increase of the grinding velocity,whereas the depth of subsurface damage decreases monotonically.The change of the subsurface damage depth is not obvious as normal force increases.When the normal force is 5 N,R_a decreases obviously with the increasing grinding speed.However,when the normal force is 10 N,R_a tends to be stable.

Study on coating layer of resin bonded diamond wire saw

ZHENG Lu, GE Peiqi, BI Wenbo, YUAN Guoqiang

2016, 36(3): 6-10. doi: 10.13394/j.cnki.jgszz.2016.3.0002

Abstract(296)

PDF 963KB(14)

Abstract:
In order to overcome the deficiencies of resin bonded diamond wire saw,such as low abrasive holding strength,poor wear resistance and heat resistance,new experiment is carried out by using different coating layer components through orthogonal experiments.It is also studied that the effect of components on performance of the wire saw by cutting mono-crystalline silicon.Resultsshow that the optimal parameters in the components are mass ratio of epoxy resin and phenolic resin 2.5:1,toughening agent CTBN 13wt%,coupling agent KH-550 1wt%,nano-SiO₂ particle 3wt%,and the content of diamond abrasive 500 mg/mL.In this condition,the resin bonded diamond wire saw made in this condition has better comprehensive performance in terms of material removal rate,wear rate,coating layer bonding force and cutting quality of workpiece.

New progress on the improvement of adhesive strength of HFCVD diamond coating

JIAN Xiaogang, ZHU Zhengyu, LEI Qiang

2016, 36(3): 11-16. doi: 10.13394/j.cnki.jgszz.2016.3.0003

Abstract(478)

PDF 998KB(13)

Abstract:
Diamond coated cemented carbide cutting tools have a broad industrial application prospect,while one of the main obstacles that hinder the application of the coating is that the adhesive strength of film-substrate interface is poor,which seriously affects its normal service life.Therefore,improving the film-substrate adhesive strength and ensuring the normal service life of the tool have become the main problems to be solved when industrializing diamond coated tools.In this paper,a series of new achievements on improving the film-substrate adhesive strength of cemented carbide substrate diamond coating has been introduced,and new ideas for further improvement are proposed in order to promote the industrial application of the hot filament chemical vapor deposition(HFCVD)diamond coated tools.

Simulation of temperature field when polishing germanium wafer using ice-bonded-abrasive polishing pad

WANG Yong, SUN Yuli, TANG Suyang, LIU Zhigang, ZUO Dunwen

2016, 36(3): 17-22. doi: 10.13394/j.cnki.jgszz.2016.3.0004

Abstract(312)

PDF 1848KB(7)

Abstract:
The finite element model is established using ABAQUS to simulate the value of temperature fields for ice-bonded-abrasive pad polishing germanium wafer.Temperature contour map and melting thickness value of the pad are obtained and the results of FEM are verified by experiments.FEM results show that the main reason of ice melting is not frictional heat but air convection surrounding the tool.The pad temperature increases fast at the beginning and then slows down.The temperature in the middle of the pad is higher than those in the inner ring and outer ring and the outer ring temperature is higher than that in the inner ring.The thermic effect of friction is more and more obvious as time goes by.The ice-bonded-abrasive polishing pad has excellent self-sharpening performance and service life when polishing time is longer than 1366 s,ambient temperature higher than 0℃,cylinder pressure 20 N,and rotating speed 200 r/min.

Research on stress and subsurface damage on silicon wafer machined by rotational grinding

XU Shance, CAO Zhihe, WANG Ziguang, ZHOU Ping

2016, 36(3): 23-27. doi: 10.13394/j.cnki.jgszz.2016.3.0005

Abstract(360)

PDF 1866KB(10)

Abstract:
The stress condition of local area in a wafer is acquired.By measuring the flatness of local area in the tested wafer,the planar principal stresses and their directions are solved using inverse calculation.The analysis result based on diamond ground(100)silicon wafer shows that the stress condition at different locations on the wafer does not consist well with the average stress solved by conventional methods using Stoney's equation.The stress condition depends on its location on the wafer.Moreover,taper polishing is adopted to test the depth of subsurface damage,which reveals that the depth of damage layer is about 0.4 μm with various condition and there are no distinct relationships between machining stress and subsurface damage.

Experiment study on single crystal diamond micro-tool sharpening

YAO Chenjiao, LI Liang, QIN Zilong

2016, 36(3): 28-32. doi: 10.13394/j.cnki.jgszz.2016.3.0006

Abstract(270)

PDF 2835KB(19)

Abstract:
The sharpness of the tool cutting edge is one of the important factors affecting the quality of the product.To improve the quality of cutting edge and increase the processing efficiency,four different types of scaife,namely copper scaife,iron scaife,copper based tungsten carbide scaife and aluminum based silicon carbide scaife,are used in the experiments for an optimized selection.The surface topography and materiall removal rate of ground scaife,as well as edge radius and surface topography of single crystal diamond micro-tool are investigated for each experiment,respectively.The experimental results show that the better cutting edge,higher surface quality and quicker material removal rate could be achieved when using copper based tungsten carbide scaife,and the edge radius can be stabilized at less than 1 μm.It's also shown that tool quality is relatively good when processed by aluminum based silicon scaife,while using copper scaife and iron scaife could not ensure the integrity of single crystalline diamond.

Simulation method of grinding wheel topography

CAO Youwei, QIAO Guochao

2016, 36(3): 33-37. doi: 10.13394/j.cnki.jgszz.2016.3.0007

Abstract(2860)

PDF 1365KB(116)

Abstract:
Surface topography of grinding wheel has tremendous influence on grinding process and machined surface quality,but it is difficult to describe the surface topography of grinding wheel due to the randomness of abrasive grains distributed on grinding wheel surface.Through sampling and data processing for grinding wheel topography,the mathematical equation of grinding wheel topography are gained by combining statistical theory and Johnson transformation method,based on which the grinding wheel topography are simulated.Some parameters of Birmingham 14 are chosen to compare the measured topography and simulated topography.The results indicate that there is a good consistency between the two,while the average deviation of six parameters is only 2.97%.It verified the correctness of the simulation method adequately.

Research on the interface relation between TiN_0.3/AlN and CBN in PCBN sintering body

DENG Hua, XING Ying, WANG Mingzhi, XU Shuai

2016, 36(3): 38-42. doi: 10.13394/j.cnki.jgszz.2016.3.0008

Abstract(284)

PDF 1469KB(5)

Abstract:
To solve the problems in dry cutting with traditional bond polycrystalline cubic boron nitride(PCBN),such as low heat resistance,non-stoichiometric ration TiN_0.3 is used to prepare new bonding system of PCBN.SEM,XRD and EDS are used to observe the polished surface and fracture of the samples,as well as the components and element distribution at the interface,thus analyzing bonding status of TiN_0.3 to CBN and TiN_0.3/AlN to CBN.Expansion coefficient and hardness are tested using DIL and FM equipment to discuss the difference between thermal expansion coefficients of TiN and CBN and the effect of this difference on the sintered body.Furthermore,AlN is introduced to reduce the effect of expansion coefficient.After coating Ti on CBN surface,TiN_0.3 and TiN_0.3/AlN are better bonded with CBN.The resultant at the interface of CBN to TiN_0.3 or TiN_0.3/AlN are analyzed,as well as its function in PCBN.

Investigation on the chemical mechanical polishing of A-plane sapphire

WANG Jinpu, BAI Linshan, CHU Xiangfeng

2016, 36(3): 43-49. doi: 10.13394/j.cnki.jgszz.2016.3.0009

Abstract(426)

PDF 1056KB(8)

Abstract:
Chemical mechanical polishing is implemented on A-plane sapphire using nano-Al₂O₃ as abrasive to investigate the effect of concentration and particle size of Al₂O₃,polishing time,polishing pressure and the concentration of NH₄F on material removal rate(MRR)and surface roughness of Aplane sapphire.The surface roughness was measured by atomic force microscopy(AFM).The results showed that polishing performance is good with MRR of 18.2nm/min and R_a 22.3 nm when polished at pH=4.0,16.39 kPa for 40 min with NH₄F mass fraction 0.6% NH₄F and 50 nm Al₂O₃ mass fraction 1%.

Study on the self-propagation high temperature sintering of Ni-TiC-Diamond

LIANG Baoyan, ZHANG Wangxi, SHI Dongli, MU Yunchao

2016, 36(3): 50-53. doi: 10.13394/j.cnki.jgszz.2016.3.0010

Abstract(283)

PDF 1542KB(12)

Abstract:
Ni-TiC boned diamond composites are fabricated by self-propagation high temperature sintering(SHS)from Ni/TiC/graphite/diamond powders.Effect of diamond size and content on the microstructure and phase composition of obtained samples is studied.The results show that the main phases of the products are Ni,TiC and diamond by SHS.When mole ratio of Ti and C is 1:1in the raw materials,it is difficult to obtain good coating on the surface of diamond by adjusting diamond content and size.Good coating can only be obtained when diamond size is finer(20 μm).Appropriate increasing Ti content in the raw materials may form uniform Ni-TiC complex coating on the surface of diamond.The size of TiC grains are about 1 μm.

Simulation of single grain grinding in rail grinding based on SPH method

SHANG Wei, WANG Wenjian, GUO Jun, LIU Qiyue

2016, 36(3): 54-59,64. doi: 10.13394/j.cnki.jgszz.2016.3.0011

Abstract(331)

PDF 1890KB(8)

Abstract:
In order to study the material removal mechanism of rail grinding,smoothed particle hydrodynamics(SPH)method is used to simulate the single grain cutting process of rail grinding.In this work,single grains with different geometries,cutting depths and negative rake angles are assumed to cut workpieces.Changes of cutting force,cutting force ratio,stress and deformation of the workpiece are analyzed.Resultsshow that material flow generates burr and chip due to grain pressing,and that the machined surface is superior when the grain is pyramid.In addition,the cutting force increases with increase of cutting depth.Bigger negative rake angle leads to higher cutting force and cutting force ratio,as well as more obvious sawtooth shapd chips.

Research progress of diamond particles composite packing materials

HE Jingyuan, LI Zhengxin

2016, 36(3): 60-64. doi: 10.13394/j.cnki.jgszz.2016.3.0012

Abstract(400)

PDF 754KB(15)

Abstract:
Research situation,applications,function and principle of diamond in the electronic packaging material are briefly summarized.The development trend of diamond in packaging materials and its impact on superhard materials and product are mainly discussed.

Effect of SiC size on dress ceramic diamond lapping disc

SUN Penghui, YAN Ning, LI Xuewen, ZHAO Mengyue, HAN Xin, LI Henan, ZHAO Xinghao

2016, 36(3): 65-68. doi: 10.13394/j.cnki.jgszz.2016.3.0013

Abstract(331)

PDF 2283KB(15)

Abstract:
The effect of grit size on dressing performance of SiC ring when dressing ceramic diamond lapping disc is studied.SiC dressing rings with different grit sizes are tested to dress M20/30 ceramic diamond discs.Surface topography,durability,and process efficiency of the discs are analyzed.Resultsshow that lapping discs dressed with 240^# SiC performs best sharpness and surface topography,when dressing parameters are up disc speed of 12 r/min,down disc speed of 12 r/min,inner ring speed of 12 r/min and pre-pressure of 0.2 MPa.

Research on application of silicon in iron-copper alloy powder production by atomization process

GU Yi, LI Hui, JIANG Xin, GAO Ying, LIU Xiaohua

2016, 36(3): 69-71,75. doi: 10.13394/j.cnki.jgszz.2016.3.0014

Abstract(259)

PDF 842KB(5)

Abstract:
Fe-Cu40 alloy powder is prepared by the water-atomization method.The property of Fe-Cu40 powder is compared at different dosages of ferrosilicon.Accordingly,the effect of ferrosilicon dosage on the powder property is clarified.The results show that excellent deoxidation efficiency is obtained when ferrosilicon is used in the water-atomization process for the production of Fe-Cu40 alloy powder.When the mass fraction of Si in the ferrosilicon is below 1.5%,the oxygen content in the semi-finished product can be reduced greatly,therefore decreasing the oxygen content of final product.But the dosage of ferrosilicon should be reduced when producing the powder of high hardness and bending strength.

Reliability and sensitivity of diamond circular saw blade

ZHANG Yunfeng, CUI Mingming

2016, 36(3): 72-75. doi: 10.13394/j.cnki.jgszz.2016.3.0015

Abstract(301)

PDF 1063KB(10)

Abstract:
Severe vibration frequently happens on diamond circular saw blade during the cutting process.The stochastic finite-element method is applied to analyze diamond circular saw blade,and the Monte-Carlo probability designed method to study the reliability and sensitivity by conducting cycle sampling of ϕ350 mm diamond circular saw blade for 1000 times.The study states that the unreliability increases with the threshold value rising,and that the vibration sensitivity is greatly affected by the thickness of corresponding diamond circular saw blade.The result will play an essential role in optimizing the structure,prolonging the service life and enhancing saw cutting quality of the diamond circular saw blade.

Pin roll removal machine applied on cubic press

CHEN Geng, QIU Dongfeng, WU Xiuwen, ZHAO Dechao

2016, 36(3): 76-78. doi: 10.13394/j.cnki.jgszz.2016.3.0016

Abstract(299)

PDF 1283KB(6)

Abstract:
Since pin rolls of cubic press are hard to install and remove,apin roll removal machine is designed after studying the connection technology,which could mechanize pin roll removal.Prototype tests by customers show that this machine satisfies application requirement at reliable quality,which improves efficiency and deceases cost of pin roll removal.It also provides methods and reference for mechanization and automation of diamond industry.

2016 Vol. 36, No. 3

NewsMore>