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Papers - Yan, Jiwang

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Noncontact on-machine measurement system based on capacitive displacement sensors for single-point diamond turning

X. Li, Z. Zhang, H. Hu, Y. Li, L. Xiong, X. Zhang, J. Yan

Optical Engineering (Optical Engineering) 57 ( 4 ) 044105 2018.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 00913286

© 2018 Society of Photo-Optical Instrumentation Engineers (SPIE). On-machine measurements can improve the form accuracy of optical surfaces in single-point diamond turning applications; however, commercially available linear variable differential transformer sensors are inaccurate and can potentially scratch the surface. We present an on-machine measurement system based on capacitive displacement sensors for high-precision optical surfaces. In the proposed system, a position-Trigger method of measurement was developed to ensure strict correspondence between the measurement points and the measurement data with no intervening time-delay. In addition, a double-sensor measurement was proposed to reduce the electric signal noise during spindle rotation. Using the proposed system, the repeatability of 80-nm peak-To-valley (PV) and 8-nm root-mean-square (RMS) was achieved through analyzing four successive measurement results. The accuracy of 109-nm PV and 14-nm RMS was obtained by comparing with the interferometer measurement result. An aluminum spherical mirror with a diameter of 300 mm was fabricated, and the resulting measured form error after one compensation cut was decreased to 254 nm in PV and 52 nm in RMS. These results confirm that the measurements of the surface form errors were successfully used to modify the cutting tool path during the compensation cut, thereby ensuring that the diamond turning process was more deterministic. In addition, the results show that the noise level was significantly reduced with the reference sensor even under a high rotational speed.

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Characterization of recrystallized depth and dopant distribution in laser recovery of grinding damage in single-crystal silicon

K. Niitsu, Y. Tayama, T. Kato, H. Maehara, J. Yan

Materials Science in Semiconductor Processing (Materials Science in Semiconductor Processing) 82 54 - 61 2018.04

Research paper (scientific journal), Joint Work, Accepted, ISSN 13698001

© 2018 Elsevier Ltd A nanosecond pulsed Nd:YAG laser was irradiated on a boron-doped single-crystal silicon wafer with a diamond grinding finish to recover the grinding-induced subsurface damage. In order to visualize and measure the depth of the laser melted/recrystallized layer, small-angle beveled polishing was performed in pure water followed by KOH etching. It enabled the direct observation of the recrystallized region using a differential interference microscope and the measurement of its depth using a white light interferometer. Crystallinity analysis of the recrystallized region was carried out by using laser micro-Raman spectroscopy, and the dopant concentration profile was characterized by using radio frequency glow discharge optical emission spectrometry (rf-GD-OES). The results showed that the crystallinity and boron distribution in the recrystallized region changed after laser recovery. The dopant concentration becomes higher at the boundary of the recrystallized region and the bulk. This study demonstrates the possibility of boron concentration control by using suitable laser parameters.

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Fracture toughness and sliding properties of magnetron sputtered CrBC and CrBCN coatings

Q. Wang, F. Zhou, Q. Ma, M. Callisti, T. Polcar, J. Yan

Applied Surface Science (Applied Surface Science) 443 635 - 643 2018.03

Research paper (scientific journal), Joint Work, Accepted, ISSN 01694332

© 2018 Elsevier B.V. CrBC and CrBCN coatings with low and high B contents were deposited on 316L steel and Si wafers using an unbalanced magnetron sputtering system. Mechanical properties including hardness (H), elastic modulus (E) and fracture toughness (K Ic ) as well as residual stresses (σ) were quantified. A clear correlation between structural, mechanical and tribological properties of coatings was found. In particular, structural analyses indicated that N incorporation in CrBC coatings with high B content caused a significant structural evolution of the nanocomposite structure (crystalline grains embedded into an amorphous matrix) from nc-CrB 2 /(a-CrB x , a-BC x ) to nc-CrN/(a-BC x , a-BN). As a result, the hardness of CrBC coating with high B content decreased from 23.4 to 16.3 GPa but the fracture toughness was enhanced. Consequently, less cracks initiated on CrBCN coatings during tribological tests, which combined with the shielding effect of a-BN on wear debris, led to a low friction coefficient and wear rate.

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Ultraprecision cutting of fluoride glass

ISHIZUKA Jun, NAGASAWA Keisuke, MIKAMI Masayuki, YAN Jiwang

Journal of the Japan Society for Abrasive Technology (The Japan Society for Abrasive Technology) 62 ( 2 ) 88 - 93 2018.02

Accepted, ISSN 0914-2703

Severe diamond tool wear may be caused by a chemical reaction between SiO2 in glass and diamond during ultraprecision cutting of silica glass, because silica glass is based on SiO2. This study demonstrated that adopting fluoride glass, which has no SiO2 constituent, as the workpiece reduced tool edge retreat to 1/22 of that of silica glass. This was because the fluoride glass contains no SiO2, which reacts chemically with diamond and leads to severe tool wear. Ductile mode cutting of fluoride glass was realized for long cutting distance. As an application, an aspherical glass lens was produced by ultraprecision cutting. In addition, the tool wear, surface generation, and chip formation mechanisms were investigated.

Ultraprecision cutting of single-crystal calcium fluoride for fabricating micro flow cells

R. Komiya, T. Kimura, T. Nomura, M. Kubo, J. Yan

Journal of Advanced Mechanical Design, Systems, and Manufacturing (Journal of Advanced Mechanical Design, Systems and Manufacturing) 12 ( 1 ) 17-00388, 1 - 13 2018.02

Research paper (scientific journal), Joint Work, Accepted

© 2018 The Japan Society of Mechanical Engineers. Single-crystal infrared (IR) spectroscopy is a promising method for protein structure analysis, where a protein crystal sample is fixed in a micro flow cell. Single-crystal calcium fluoride (CaF2) is expected as the flow cell substrate material for its excellent optical property. However, CaF2 is a highly brittle material having strong anisotropy, thus is extremely difficult to machine. Up to date, there is no available literature on fabrication of CaF2 flow cells. In this study, micro flow cells of single-crystal CaF2 were fabricated by ultraprecision cutting technology. Fly cutting was conducted using a single-crystal diamond tool having straight edges to generate a depth-varying rectangle cross section for the flow cell. The effects of cutting direction, workpiece orientation, undeformed chip thickness and tool rake angle on cutting behavior were investigated. Based on experiments and analysis, optimal conditions for ductile machining of micro grooves in CaF2 were identified. As a result, a 10 μm deep CaF2 micro flow cell with surface roughness of 2.4 nmRa was successfully fabricated. Using the fabricated flow cell, IR spectroscopic analysis of a protein single crystal at room temperature was succeeded. This study demonstrated the effectiveness of ultraprecision cutting technology in CaF2 micro flow cell fabrication, which contributes to the IR analysis of protein, and in turn, the advance of life science.

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Nanometer-scale chip formation and surface integrity of pure titanium in diamond turning

M. Heidari, J. Yan

International Journal of Advanced Manufacturing Technology (International Journal of Advanced Manufacturing Technology) 95 ( 1-4 ) 479 - 492 2018.02

Research paper (scientific journal), Joint Work, Accepted, ISSN 02683768

© 2017, Springer-Verlag London Ltd. Titanium is attracting great attentions in aerospace and medical applications where high surface quality plays an important role in improving the product performance. For developing nano-precision machining technology for titanium, clarification of the nanometer-scale chip formation mechanism is essential. In this study, the surface formation mechanism of pure titanium in ultraprecision cutting tests using single-crystal diamond tools was investigated. The results demonstrated that decreasing undeformed chip thickness from the micrometer scale down to the nanometer scale had profound impacts on the shear angle, specific cutting force, and chip morphology. Chip tearing phenomenon occurred when undeformed chip thickness is smaller than a critical value (~ 100 nm), which significantly affected the chip morphology and machined surface integrity. In nanometer-scale cutting, tool feed mark is no longer a major reason of surface roughness; instead, material plucking, debris, scratches, and chip adhesion influenced the surface integrity. The high pressure generated in the nanometer-scale cutting caused a hardness increase in workpiece material and promoted workpiece material adhesion to the tool surface, as well as tool wear.

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Ultraprecision cutting of fluoride glass - Fundamental investigation on surface formation and tool damage -

J. Ishizuka, K. Nagasawa, M. Mikami, J. Yan

Journal of the Japan Society for Abrasive Technology 62 ( 2 ) 88 - 93 2018.02

Research paper (scientific journal), Joint Work, Accepted

Precision slicing of single-crystal SiC using extremely fine fixed-abrasive diamond wire

T. Suzuki, T. Otsuki, J. Yan

Transactions of the JSME 84 ( 857 ) 1 - 18 2018.01

Research paper (scientific journal), Joint Work, Accepted

Comparative study of phase transformation in single-crystal germanium during single and cyclic nanoindentation

K. Kosai, H. Huang, J. Yan

Crystals 7 ( 333 ) 1 - 11 2017.11

Research paper (scientific journal), Joint Work, Accepted

Fabrication of hexagonal microlens arrays on single-crystal silicon by tool-servo segment turning method

M. Mukaida, J. Yan

Micromachines 8 ( 323 ) 1 - 18 2017.11

Research paper (scientific journal), Joint Work, Accepted

An investigation on the crack resistance of CrN, CrBN and CrTiBN coatings via nanoindentation

Q. Wang, F. Zhou, Z. Zhou, L. K-Y Li, J. Yan

Vacuum 145 186 - 193 2017.10

Research paper (scientific journal), Joint Work, Accepted

Mechanisms of material removal and subsurface damage in fixed-abrasive diamond wire slicing of single-crystalline silicon

T. Suzuki, Y. Nishino, J. Yan

Precision Engineering 50 32 - 43 2017.09

Research paper (scientific journal), Joint Work, Accepted

Effect of surfactants and additives on electrical discharge machining of Reaction Bonded Silicon Carbide

M. R. A. Razak, P. J. Liew, N. I. S. Hussein, Q. Ahsan, J. Yan

ARPN Journal of Engineering and Applied Sciences 12 ( 14 ) 4334 - 4339 2017.09

Research paper (scientific journal), Joint Work, Accepted

Investigating shear band interaction in metallic glasses by adjacent nanoindentation

H. Huang, J. Yan

Materials Science & Engineering A 704 375 - 385 2017.08

Research paper (scientific journal), Joint Work, Accepted

Fabrication of Microstructures on Single-crystal Diamond by Press Imprinting Utilizing Pure Iron Molds

Y. Imoto, J. Yan

Journal of the Japan Society for Precision Engineering 83 ( 8 ) 770 - 774 2017.08

Research paper (scientific journal), Joint Work, Accepted

Laser Irradiation Responses of a Single-Crystal Diamond Produced by Different Crystal Growth Methods

N. Takayama, J. Yan

Applied Sciences 7 ( 815 ) 1 - 15 2017.08

Research paper (scientific journal), Joint Work, Accepted

A nanosecond time-resolved XFEL analysis of structural changes associated with CO release from cytochrome c oxidase

A. Shimada, M. Kubo, S. Baba, K. Yamashita, K. Hirata, G. Ueno, T. Nomura, T. Kimura, K. Shinzawa-Itoh, J. Baba, K. Hatano, Y. Eto, A. Miyamoto, H. Murakami, T. Kumasaka, S. Owada, K. Tono, M. Yabashi, Y. Yamaguchi, S. Yanagisawa, M. Sakaguchi, T. Ogura, R. Komiya, J. Yan, E. Yamashita, M. Yamamoto, H. Ago, S. Yoshikawa, T. Tsukihara

Science Advances 3 ( e1603042 ) 1 - 12 2017.07

Research paper (scientific journal), Joint Work, Accepted

Ultraprecision surface flattening of porous silicon by diamond turning

M. Heidari, J. Yan

Precision Engineering 49 262 - 277 2017.07

Research paper (scientific journal), Joint Work, Accepted

Fabrication of single-crystal silicon micro pillars on copper foils by nanosecond pulsed laser irradiation

J. Yan, J. Noguchi, Y. Terashi

CIRP Annals – Manufacturing Technology 66 ( 1 ) 253 - 256 2017.07

Research paper (scientific journal), Joint Work, Accepted

On the phase transformation of single-crystal 4H-SiC during nanoindentation

M. Matsumoto, H. Huang, H. Harada, K. Kakimoto,　J. Yan

Journal of Physics D: Applied Physics 50 ( 265303 ) 1 - 9 2017.06

Research paper (scientific journal), Joint Work, Accepted

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