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Chinese Journal of Aeronautics 2024年第5期37卷 570-585页

作者： Biao QIN Henan LIU Jian CHENG Jinchuan TIAN Jiangang SUN Zihan ZHOU Chuanzhen MA Mingjun CHEN State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China Center for Precision Engineering Harbin Institute of TechnologyHarbin 150001China

As for the ultra-precision grinding of the hemispherical fused silica resonator,due to the hard and brittle nature of fused silica,subsurface damage(SSD)is easily generated,which enormously influences the performance of such ***,ultra-precision grinding experiments are carried out to investigate the surface/subsurface quality of the hemispherical resonator machined by the small ball-end fine diamond grinding *** influence of grinding parameters on the surface roughness(SR)and SSD depth of fused silica samples is then *** experimental results indicate that the SR and SSD depth decreased with the increase of grinding speed and the decrease of feed rate and grinding *** addition,based on the material strain rate and the maximum undeformed chip thickness,the effect of grinding parameters on the subsurface damage mechanism of fused silica samples is ***,a multi-step ultra-precision grinding technique of the hemispherical resonator is proposed based on the interaction influence between grinding depth and feed ***,the hemispherical resonator is processed by the proposed grinding technique,and the SR is improved from 454.328 nm to 110.449 nm while the SSD depth is reduced by 94%from 40μm to 2.379μ*** multi-step grinding technique proposed in this paper can guide the fabrication of the hemispherical resonator.

关键词： Fused silica Ultra-precision grinding Hemispherical resonator subsurface damage Grinding technique

subsurface damage and bending strength analysis for ultra-thin and flexible silicon chips

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Science China(Technological Sciences) 2023年第1期66卷 215-222页

作者： JIAN Wei WANG ZhaoXian JIN Peng ZHU Longji CHEN Ying FENG Xue Key Laboratory of Applied Mechanics of Ministry of Education Department of Engineering MechanicsTsinghua UniversityBeijing100084China Center for Flexible Electronics Technology Tsinghua UniversityBejing 100084China Institute of Flexible Electronics Technology of Tsinghua University Jiaxing Jiaxing314000China Qiantang Scienceand Technology Innovation Center Hangzhou310016China

subsurface damage(SSD) is an unavoidable problem in the precision mechanical grinding for preparing ultra-thin and flexible silicon chips. At present, there are relatively few studies on the relationship between SSD and the bending strength of ultra-thin chips under different grinding parameters. In this study, SSD including amorphization and dislocation is observed using a transmission electron microscope. Theoretical predictions of the SSD depth induced by different processing parameters are in good agreement with experimental data. The main reasons for SSD depth increase include the increase of grit size, the acceleration of feed rate, and the slowdown of wheel rotation speed. Three-point bending test is adopted to measure the bending strength of ultra-thin chips processed by different grinding conditions. The results show that increasing wheel rotation speed and decreasing grit size and feed rate will improve the bending strength of chips, due to the reduction of SSD depth. Wet etching and chemical mechanical polishing(CMP) are applied respectively to remove the SSD induced by grinding, and both contribute to providing a higher bending strength, but in comparison, CMP works better due to a smooth surface profile. This research aims to provide some guidance for optimizing the grinding process and fabricating ultra-thin chips with higher bending strength.

关键词： ultra-thin chip flexible chip subsurface damage bending strength mechanical grinding

subsurface damage pattern and formation mechanism of monocrystalline β-Ga_(2)O_(3) in grinding process

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Frontiers of Mechanical Engineering 2022年第2期17卷 117-127页

作者： Xin YANG Renke KANG Shang GAO Zihe WU Xianglong ZHU Key Laboratory for Precision and Non-Traditional Machining Technology of Ministry of Education Dalian University of TechnologyDalian 116024China

Monocrystalline beta-phase gallium oxide (β-Ga_(2)O_(3)) is a promising ultrawide bandgap semiconductor material. However, the deformation mechanism in ultraprecision machining has not yet been revealed. The aim of this study is to investigate the damage pattern and formation mechanism of monocrystalline β-Ga_(2)O_(3)in different grinding processes. Transmission electron microscopy was used to observe the subsurface damage in rough, fine, and ultrafine grinding processes. Nanocrystals and stacking faults existed in all three processes, dislocations and twins were observed in the rough and fine grinding processes, cracks were also observed in the rough grinding process, and amorphous phase were only present in the ultrafine grinding process. The subsurface damage thickness of the samples decreased with the reduction in the grit radius and the grit depth of cut. subsurface damage models for grinding process were established on the basis of the grinding principle, revealing the mechanism of the mechanical effect of grits on the damage pattern. The formation of nanocrystals and amorphous phase was related to the grinding conditions and material characteristics. It is important to investigate the ultraprecision grinding process of monocrystalline β-Ga_(2)O_(3). The results in this work are supposed to provide guidance for the damage control of monocrystalline β-Ga_(2)O_(3)grinding process.

关键词： monocrystalline beta-phase gallium oxide grinding process subsurface damage nanocrystals amorphous phase

subsurface damage in Scratch Testing of Potassium Dihydrogen Phosphate Crystal

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Chinese Journal of Mechanical Engineering 2009年第1期22卷 15-20页

作者： WANG Ben WU Dongjiang GAO Hang KANG Renke GUO Dongming Key Laboratory for Precision and Non-traditional Machining Technology of Ministry of Education Dalian University of Technology Dalian 116024 China

Potassium dihydrogen phosphate （KDP） is an important electro-optic crystal, often used for frequency conversion and Pockels cells in large aperture laser systems. To investigate the influence of anisotropy to the depth of subsurface damage and the profiles of cracks in subsurface of KDP crystal, an experimental study was made to obtain the form of subsurface damage produced by scratches on KDP crystal in [100], [120] and [110] crystal directions on （001） crystal plane. The results indicated that there were great differences between depth and crack shape in different directions. For many slip planes in KDP, the plastic deformation and cracks generated under pressure in the subsurface were complex. Fluctuations of subsurface damage depth at transition point were attributed to the deformation of the surface which consumed more energy when the surface deformation changed from the mixed region of brittle and plastic to the complete brittle region along the scratch. Also, the process of subsurface damage from shallow to deep, from dislocation to big crack in KDP crystal with the increase of radial force and etch pit on different crystal plane were obtained. Because crystallographic orientation and processing orientation was different, etching pits on （100） crystal plane were quadrilateral while on （110） plane and （120） plane were trapezoidal and triangular, respectively.

关键词： potassium dihydrogen phosphate (KDP) crystal scratch subsurface damage

Understanding the formation mechanism of subsurface damage in potassium dihydrogen phosphate crystals during ultraprecision fly cutting

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Advances in Manufacturing 2019年第3期7卷 270-277页

作者： Yong Zhang Ning Hou Liang-Chi Zhang School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001People's Republic of China School of Mechatronics Engineering Shenyang Aerospace UniversityShenyang 110136People's Republic of China Laboratory for Precision and Nano Processing Technologies School of Mechanical and Manufacturing EngineeringThe University of New South WalesSydneyNSW 2052Australia

Potassium dihydrogen phosphate(KDP)crystals play an important role in high-energy laser systems,but the laser damage threshold(LDT)of KDP components is lower than *** LDT is significantly influenced by subsurface damage produced in KDP ***,it is very challenging to detect the subsurface damage caused by processing because a KDP is soft,brittle,and sensitive to the external environment(e.g.,humidity,temperature and applied stress).Conventional characterization methods such as transmission electron microscopy are ineffective for this *** paper proposes a nondestructive detection method called grazing incidence X-ray diffraction(GIXD)to investigate the formation of subsurface damage during ultra-precision fly cutting of KDP *** crystal planes,namely(200),(112),(312),(211),(220),(202),(301),(213),(310)and(303),were detected in the processed subsurface with the aid of GIXD,which provided very different results for KDP crystal *** results mean that single KDP crystals change into a lattice misalignment structure(LMS)due to mechanical stress in the *** crystal planes match the slip systems of the KDP crystals,implying that dislocations nucleate and propagate along slip systems to result in the formation of the LMS under shear and compression *** discovery of the LMS in the subsurface provides a new insight into the nature of the laser-induced damage of KDP crystals.

关键词： Potassium dihydrogen phosphate(KDP)crystals subsurface damage Lattice misalignment structure Slip systems

subsurface damage in the Monocrystal Silicon Grinding on Atomic Scale

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Journal of Semiconductors 2007年第9期28卷 1353-1358页

作者：郭晓光郭东明康仁科金洙吉大连理工大学精密与特种加工教育部重点实验室大连116023

A molecular dynamics （MD） simulation is carried out to analyze the effect of cutting edge radius,cutdepth, and grinding speed on the depth of subsurface damage layers in monocrystal silicon grinding processes on an atomic scale. The results show that when the cutting edge radius decreases in the nanometric grinding process with the same cut-depth and grinding speed, the depth of the damage layers and the potential energy between the silicon atoms decrease too. Also, when the cut depth increases, both the depth of the damage layers and the potential energy between silicon atoms increase. When the grinding speed is between 20 and 200m/s,the depth of the damage layers does not change much with the increase of the grinding speed under the same cutting edge radius and cut depth conditions. This means that the MD simulation is not sensitive to changes in the grinding speed, and thus increasing the grinding speed properly can shorten the sion,the subsurface damage of monocrystal silicon is silicon atoms, which is verified by the ultra-precision simulation time and enlarge the simulation scale. In conclumainly based on the change of the potential energy between grinding and CMP experiments.

关键词： molecular dynamics grinding subsurface damage monocrystal silicon

Experimental investigation of subsurface damage depth of lapped optics by fluorescent method

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Journal of Central South University 2018年第7期25卷 1678-1689页

作者： WANG Hong-xiang HOU Jing WANG Jing-he ZHU Ben-wen ZHANG Yan-hu School of Mechatronics Engineering Harbin Institute of TechnologyHarbin 150001China

subsurface defects were fluorescently tagged with nanoscale quantum dots and scanned layer by layer using confocal fluorescence microscopy to obtain images at various depths. subsurface damage depths of fused silica optics were characterized quantitatively by changes in the fluorescence intensity of feature points. The fluorescence intensity vs scan depth revealed that the maximum fluorescence intensity decreases sharply when the scan depth exceeds a critical value. The subsurface damage depth could be determined by the actual embedded depth of the quantum dots. Taper polishing and magnetorheological finishing were performed under the same conditions to verify the effectiveness of the nondestructive fluorescence method. The results indicated that the quantum dots effectively tagged subsurface defects of fused-silica optics, and that the nondestructive detection method could effectively evaluate subsurface damage depths.

关键词： optics subsurface defect nondestructive detection lapping subsurface damage

Methods for Detection of subsurface damage:A Review

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 23-36页

作者： Jing-fei Yin Qian Bai Bi Zhang Key Laboratory for Precision and Non-traditional Machining of Ministry of Education Dalian University of Technology Department of Mechanical and Energy Engineering South University of Science and Technology

subsurface damage is easily induced in machining of hard and brittle materials because of their particular mechani?cal and physical properties. It is detrimental to the strength,performance and lifetime of a machined part. To manu?facture a high quality part,it is necessary to detect and remove the machining induced subsurface damage by the subsequent processes. However,subsurface damage is often covered with a smearing layer generated in a machining process,it is rather di cult to directly observe and detect by optical microscopy. An e cient detection of subsur?face damage directly leads to quality improvement and time saving for machining of hard and brittle materials. This paper presents a review of the methods for detection of subsurface damage,both destructive and non?destructive. Although more reliable,destructive methods are typically time?consuming and confined to local damage infor?mation. Non?destructive methods usually su er from uncertainty factors,but may provide global information on subsurface damage distribution. These methods are promising because they can provide a capacity of rapid scan and detection of subsurface damage in spatial distribution.

关键词： subsurface damage Hard and brittle material Taper polishing Measurement Laser scattering

Relationship between subsurface damage and surface roughness of ground optical materials

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Journal of Central South University of Technology 2007年第4期14卷 546-551页

作者：李圣怡王卓吴宇列 College of Mechatronic Engineering and Automation National University of Defense Technology

A theoretical model of relationship between subsurface damage and surface roughness was established to realize rapid and non-destructive measurement of subsurface damage of ground optical *** condition of the model was that subsurface damage depth and peak-to-valley surface roughness are equal to depth of radial and lateral cracks in brittle surface induced by small-radius(radius≤200 μm)spherical indenter,*** contribution of elastic stress field to the radial cracks propagation was also considered in the loading *** damage depth of ground BK7 glasses was measured by magnetorheological finishing spot technique to validate theoretical ratio of subsurface damage to surface *** results show that the ratio is directly proportional to load of abrasive grains and hardness of optical materials,while inversely proportional to granularity of abrasive grains and fracture toughness of optical ***,the influence of the load and fracture toughness on the ratio is more significant than the granularity and hardness,*** measured ratios of 80 grit and 120 grit fixed abrasive grinding of BK7 glasses are 5.8 and 5.4,respectively.

关键词： subsurface damage spherical indenter optical materials grinding process magnetorheological finishing

Surface roughness and removal rate in magnetorheological finishing of a subsurface damage free surface

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Progress in Natural Science:Materials International 2005年第6期15卷 538-544页

作者： CHENG Haobo1*, WANG Yingwei2, FENG Zhijing1 and CHENG Kai3(1. State Key Laboratory of Tribiology, Tsinghua University, Beijing 100084, China 2. Department of Material Sciences, Changchun University of Science and Technology, Changchun 130021, China 3. Faculty of Information and Engineering Systems, City Campus, Leeds LS1 3HE, UK) State Key Laboratory of Tribiology Tsinghua University Beijing 100084 China Department of Material Sciences Changchun University of Science and Technology Changchun 130021 China Faculty of Information and Engineering Systems City Campus Leeds LS1 3HE United Kingdom

Based on computer-controlled optical surfacing, a new technique called magnetorheological finishing (MRF), is presented. The new technique combines the features of conventional loose abrasive machining with a wheel shaped polishing tool. The tool incorporates a host of features and has unprecedented fabricating versatility. The pre-polishing and fine polishing processes can be performed only by adjusting different parameters. The material removal function is studied theoretically and the results of simulation present a Gaussian distribution feature. Based on the established theoretical model, material removal rate experiments involving a parabolic mirror are designed and carried out to determine the effect of controllable parameters on size of the gap between the workpiece and the polishing wheel, rotating speed of the polishing wheel, concentration of volume fraction of non-magnetic particles and polishing time. Further experiments are carried out on the surface microstructure of the workpiece, the final surface roughness with an initial value of 10.98 nm reaches 1.22 nm root mean square (RMS) after 20 min of polishing. The subsurface damage experiment and the atomic force microscopy (AFM) measurement on the polished surface can also verify the feasibility of the MRF technique.

关键词： magnetorheological finishing surface roughness computer controlled optical surfacing subsurface damage removal function.