KEIO RESEARCHERS INFORMATION SYSTEM

Profile Summary 【 Display / hide 】

Profile Summary 【 Display / hide 】

• To create new products with high added value, we are conducting R&D on high-accuracy, high-efficiency, resource-saving manufacturing technologies through micro/nanometer-scale material removal, deformation, and property control. Our recent research focuses on ultra-precision mechanical fabrication, micro-nano forming/imprinting, micro electrical machining, laser machining, laser recovery, and laser Raman spectroscopy.

Career 【 Display / hide 】

Career 【 Display / hide 】

• 2000.04

  -

  2001.09

  Research Associate, Tohoku University, Graduate School of Engineering

• 2001.10

  -

  2005.03

  Associate Professor, Kitami Institute of Technology

• 2005.04

  -

  2007.03

  Associate Professor, Tohoku University, Graduate School of Engineering

• 2007.04

  -

  2012.03

  Associate Professor, Tohoku University, Graduate School of Engineering

• 2012.04

  -

  Present

  Professor, Keio University, Faculty of Science and Technology

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Academic Background 【 Display / hide 】

Academic Background 【 Display / hide 】

• 1991.07

  Jilin University, Faculty of Engineering, Department of Mechanical Engineering

  University, Graduated

• 1994.03

  Jilin University, Graduate School, Division of Engineering, Department of Mechanical Engineering

  Graduate School, Completed, Master's course

• 1996.01

  Tsinghua University, Graduate School, Division of Engineering, Department of Precision Instruments and Mechanology

  Graduate School, Withdrawal before completion, Doctoral course

• 2000.03

  Tohoku University, Graduate School, Division of Engineering, Department of Mechatronics and Precision Engineering

  Graduate School, Completed, Doctoral course

Academic Degrees 【 Display / hide 】

Academic Degrees 【 Display / hide 】

• Ph.D., Tohoku University, Coursework, 2000.03

Research Areas 【 Display / hide 】

Research Areas 【 Display / hide 】

• Manufacturing Technology (Mechanical Engineering, Electrical and Electronic Engineering, Chemical Engineering) / Manufacturing and production engineering (Precision Engineering/Mechanical manufacturing)

• Nanotechnology/Materials / Material processing and microstructure control (Material Processing/Treatment)

• Nanotechnology/Materials / Nano/micro-systems (Micro/Nanodevice)

• Nanotechnology/Materials / Composite materials and interfaces (Applied Physical Properties/Crystal Engineering)

Research Keywords 【 Display / hide 】

Research Keywords 【 Display / hide 】

• Ultraprecision machining

• Micro/nano manufacturing

• Laser processing

• Electrical discharge machining

• Nanomechanics

Books 【 Display / hide 】

Books 【 Display / hide 】

• Ultraprecision Machining and Metrology

  J. Yan, CRC Press, 2025.09,  Page： 352

  Scope: 1-352

  　View Summary

  This comprehensive introduction to ultraprecision machining and metrology provides an essential foundation for students and engineers, offering an in-depth analysis of key methods, technologies, and practical applications. Ultraprecision machining is a critical enabling technology for producing high-value mechanical, optical, optoelectronic, and biomedical components with complex geometries and extreme precision. This book delivers a structured exploration of ultraprecision machining and metrology, covering essential topics such as system configuration, tooling, machining mechanism modeling, and surface characterization. Dedicated chapters on surface and subsurface metrology, as well as the machinability of both ductile and brittle materials, make it an indispensable resource for understanding machine design, manufacturing processes, and related materials science. Ideal for students and researchers, this book serves as a vital reference for those working in precision machining, MEMS, advanced manufacturing, and precision metrology.

  • Access to Document (DOI)

• Micro and Nanoscale Laser Processing of Hard Brittle Materials

  J. Yan and N. Takayama, Elsevier B.V., 2019.11,  Page： 242

  Scope: 1-242

• Micro and Nano Fabrication Technology

  J. Yan (ed.), Springer Nature Singapore Pte Ltd., 2018.05

  Scope: 1-959

• Comprehensive Materials Processing: Volume 1-13, Second edition

  Huang W., J. Yan , 2024.01,  Page： 180-204

  Scope: Chapter 10.08 Ultra-precision grooving technologies

  　View Summary

  Fabricating microgrooves on part surfaces is a way to provide advanced functionality of the parts, which has recently increased in several fields, such as biotechnology, optics, and aerospace. Considerable progress has been achieved in groove-cutting technology with the equipment development, process optimization and mechanisms understanding. This chapter reviews the ultraprecision cutting technologies for manufacturing of microgrooves and microgroove-based microstructures on various materials. Major cutting methods and their principles/mechanisms for microgrooving have been introduced. The main challenges in the cutting of microgrooves on ductile materials and brittle materials, respectively, are pointed out. Some innovations in groove-cutting technology are also highlighted. Several aspects in demand for further research and development are provided.

  • Access to Document (DOI)

• Advanced Ceramic Coatings: Fundamentals, Manufacturing, and Classification, R. K. Gupta, A. Motallebzadeh, S. Kakooei, T. A. Nguyen, A. Behera (eds.)

  P. J. Liew, J. Yan, C. Y. Yap, Elsevier B. V., 2023.06

  Scope: Chapter 19: Electrical discharge coating with quarry dust powder suspension,  Contact page： 433-460

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Papers 【 Display / hide 】

Papers 【 Display / hide 】

• Understanding the material removal and quality improvement mechanisms in acid-metal synergistically assisted femtosecond laser drilling of CFRP composites

  An H., Qian Y., Yang Z., Huang H., Yan J.

  International Journal of Machine Tools and Manufacture 223 2026.12

  ISSN  08906955

  　View Summary

  The precision fabrication of carbon fiber reinforced plastic (CFRP) through-holes is critical for reliable component integration across aerospace, automotive, and biomedical sectors. However, existing laser-based drilling methods fundamentally fail to overcome the persistent physical bottlenecks of severe thermal damage and pronounced taper. To resolve these limitations, this study proposes a synergistic hydrochloric acid (HCl) and zinc (Zn) plate assisted laser drilling (SHAZALD) strategy. In this synergistic configuration, the HCl solution functions as a dynamic liquid heat sink, which dramatically accelerates thermal dissipation and facilitates the rapid, continuous evacuation of processing debris. Concurrently, the underlying Zn plate absorbs residual thermal energy and modulates the spatial distribution of the laser energy at the outlet interface through active reactive coupling. Demonstrated on 2.2 mm thick CFRP laminates, this novel approach effectively modulates the laser-matter interaction mechanisms during drilling. Comprehensive quantitative characterization of hole quality metrics demonstrates that SHAZALD enables the fabrication of CFRP through-holes with exceptional fidelity, achieving an exceptionally low taper of 0.029, a superior outlet roundness of 98.6%, and the near-complete elimination of outlet heat-affected zone (HAZ). The marked improvement in geometric fidelity and surface integrity translates directly into enhanced optical and mechanical properties. Through rigorous chemical characterization of the fabricated through-holes and comprehensive real-time monitoring of the drilling process, the underlying multiphase mechanisms driving this quality enhancement are elucidated as the synergistic effects of dynamic thermal extraction, thermochemical etching, and interfacial plasma-assisted trimming. Building on these fundamental insights, definitive material selection criteria for both the fluidic media and the backing substrates are established. Critically, a tailored two-step protocol that yields virtually taper-free through-holes with minimal thermal damage is further developed. This work offers crucial insights into the multiphase synergistic mechanisms of laser-CFRP interaction and provides the theoretical foundation for the fabrication of high-fidelity through-holes in advanced carbon fiber reinforced composites.

  • Access to Document (DOI)

• Atmosphere-dependent ablation behavior and mechanism in nanosecond laser processing of CFRP composites

  An H., Qian Y., Guo H., Xu P., Huang H., Yan J.

  Composites Part A: Applied Science and Manufacturing 210 2026.11

  ISSN  1359835X

  　View Summary

  Carbon fiber reinforced plastic (CFRP) is essential in lightweight structural design due to its exceptional mechanical and physical properties. Although laser processing offers an efficient method for machining CFRP, the substantial thermal damage inherent to the ablation process severely compromises structural integrity. To overcome these limitations, this study introduces an argon-assisted laser processing technique that effectively mitigates thermal damage, enabling fabrication of high-performance CFRP components. The laser ablation behavior of CFRP under air and argon atmospheres is systematically compared. Experimental and simulation results reveal that surface roughness and the width of heat-affected zone (HAZ) decrease with increasing scanning speed or scanning pitch. Crucially, argon-assisted laser processing significantly improves surface quality. Compared to processing in air, this approach yields reductions in surface roughness of up to 23.4%. Furthermore, under a laser power of 3.5 W, a scanning speed of 400 mm/s, and a scanning pitch of 30 μm, the HAZ on the right side of the laser-ablated region is reduced by a maximum of 74.3%. The underlying damage suppression mechanism involves laser energy attenuation, enhanced heat dissipation, and suppression of exothermic oxidation reactions. These findings establish argon-assisted laser processing as a promising strategy for high-fidelity manufacturing of advanced composite components.

  • Access to Document (DOI)

• Understanding the thermal and chemical contributions to the microstructural and mechanical evolution of Zr-4 alloys induced by laser-based modification strategies and gas nitriding

  Huang H., An H., Xu P., Xue H., Qian Y., Yan J.

  Journal of Materials Processing Technology 357 2026.11

  ISSN  09240136

  　View Summary

  The surface modification is imperative to mitigate defect-induced degradation and ensure the long-term structural integrity of Zr-4 alloys operating in extreme nuclear reactor environments. However, conventional surface modification of Zr-4 alloys is inherently constrained by the inseparable coupling of thermal and chemical kinetics. To disentangle these respective roles, we employ an orthogonal modulation strategy comprising three distinct pathways: laser processing in argon to examine thermal effects in the absence of chemical reactivity, gas nitriding to emphasize chemical contributions with minimal thermal input, and laser nitriding to achieve synergistic thermo-chemical coupling. The results demonstrate that thermal activation alone induces moderate hardening (3.5 GPa) through grain refinement, whereas solid-state chemical diffusion during gas nitriding yields substantial hardening (14.8 GPa) via defect annihilation and interstitial solid-solution formation. Critically, the synergistic integration of both factors in laser nitriding produces a further amplified hardness (23.5 GPa). This pronounced reinforcement arises from ZrN precipitation, which triggers pronounced grain refinement and promotes deep densification via consumption of reactive gas species. These findings provide a mechanistic basis for designing high-performance Zr-4 alloy components.

  • Access to Document (DOI)

• Crystallographic Regulation of LIPSS Formation on Metal Surface Under Randomly Polarized Nanosecond Laser Irradiation

  Wang C., Huang H., Zhang X., Huang W., Yan J.

  Laser & Photonics Reviews  2026.10

  ISSN  18638880

  　View Summary

  Laser-induced periodic surface structures (LIPSS) provide a mask-free route for fabricating periodic micro/nanostructures. However, the directional energy modulation imposed by linear polarization can often mask crystallography-dependent material responses, leaving the role of crystallographic characteristics in LIPSS formation insufficiently understood. Here, a randomly polarized nanosecond laser (1064 nm, 7 ns, 700 kHz) is employed with line-by-line scanning to weaken the fixed polarization constraint and reveal crystallographic contributions across FCC FeCoCrNiMn high-entropy alloy, laser-induced FCC+BCC 310L stainless steel, BCC 430 stainless steel, and Ni-P amorphous alloy. The crystalline systems exhibit pronounced grain-selective LIPSS formation, with the formation probability varying strongly with crystallographic orientation. Correlative electron backscatter diffraction (EBSD) analysis further shows that LIPSS orientations preferentially align with projected crystallographic slip traces, indicating that crystallographic slip geometry is closely associated with the directional selection and subsequent development of LIPSS. The FCC, FCC+BCC, and BCC systems exhibit comparable LIPSS spatial periods but progressively reduced continuity and ordering, while grain refinement decreases continuity through increased grain-boundary (GB)-related discontinuities. Comparisons with amorphous Ni-P and linearly polarized irradiation show that LIPSS formation and evolution are governed by coupling between polarization-controlled directional modulation and crystallography-mediated surface response. These findings establish a crystallography-mediated framework for understanding laser-induced surface self-organization.

  • Access to Document (DOI)

• Uniform periodic nano-patterning of metallic glass substrates via high-frequency nanosecond laser irradiation

  Qian Y., An H., Huang H., Jiang M., Yan J., Ren L.

  Nature Communications 17 ( 1 )  2026.08

  　View Summary

  Achieving high spatial uniformity in laser-induced periodic surface structures (LIPSS) has long remained elusive, as even femtosecond lasers, despite their nominally “cold” processing capability, cannot eliminate the stochastic defects that compromise long-range order. Here, we present a strategy that utilizes high-repetition-frequency nanosecond pulses, a regime traditionally deemed unsuitable for precision nano-patterning due to pronounced thermal dissipation, to fabricate one-dimensional (1D) LIPSS with uniform morphology on structurally homogeneous metallic glass (MG) substrates. This is achieved by exploiting strong inter-pulse correlation, which simultaneously moderates thermal fluctuations and sustains a coherent optical near-field to template deterministic pattern formation from stochastic seeds. Performing repeated scanning along the same single-line path transform these 1D patterns into regular two‑dimensional (2D) nanodot arrays. Finite-difference time-domain simulations reveal that a unified optical near-field interaction governs the entire structural evolution, from initial 1D ordering to subsequent 2D reconfiguration. The process preserves the MG substrate’s amorphous state and chemical composition while being inherently scalable.

  • Access to Document (DOI)

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Reviews, Commentaries, etc. 【 Display / hide 】

Reviews, Commentaries, etc. 【 Display / hide 】

• A comparison of micro-machining characteristics between cutting and laser machining

  J. Yan

  Die and Mould Technology 41 ( 8 ) 108 - 109 2026.08

  Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media), Single Work, Lead author

• Laser-Based Cutting Edge Shaping of Diamond and cBN Tools and Its Application to Functional Surface Generation

  J. Yan

  Tool Engineers 67 ( 8 ) 65 - 69 2026.08

  Article, review, commentary, editorial, etc. (scientific journal), Single Work, Lead author

• Femtosecond Pulsed Laser Machining of Fused Silica for Micro Cavities

  J. Yan

  Tool Engineers 66 ( 8 ) 83 - 87 2025.07

  Article, review, commentary, editorial, etc. (scientific journal), Single Work, Lead author

• Laser-based micro/nano machining technologies for high-value added manufacturing

  J. Yan

  Machines and Tools 14 ( 11 ) 8 - 15 2024.11

  Article, review, commentary, editorial, etc. (scientific journal), Single Work, Lead author

• Creating functional surfaces by micro/nano scale laser machining

  J. Yan

  Laser (Journal of the Japan Society of Laser Technology) 49 ( 1 ) 20 - 25 2024.11

  Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media), Single Work

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Presentations 【 Display / hide 】

Presentations 【 Display / hide 】

• Scale-bridging surface structuring for functional performance improvement of components

  J. Yan

  [International presentation]  7th CIRP CSI Conference on Surface Integrity 2024 (ブレーメン) , 

  2024.05

  , 

  Oral presentation (keynote)

• Tool Dynamics-induced Surface Topography Error in Fast Tool Servo-Based Diamond Turning of Micro Dome Arrays

  T. Hashimoto, J. Yan

  [International presentation]  7th CIRP CSI Conference on Surface Integrity 2024 (Bremen) , 

  2024.05

  , 

  Oral presentation (general)

• Influences of tool tip geometry on surface/subsurface damage formation in nanoscratching of single-crystal 4H-SiC

  W. Huang, J. Yan

  [International presentation]  7th CIRP CSI Conference on Surface Integrity 2024 (Bremen) , 

  2024.05

  , 

  Oral presentation (general)

• Ultraprecision manufacturing for small optics

  J. Yan

  [International presentation]  Nanotechnology and Precision Engineering (NPE) International Series Forum (Online) , 

  2024.04

  , 

  Oral presentation (invited, special)

• 自由曲面加工における工具姿勢に起因する切削メカニズム変化

  川上凜太朗，閻 紀旺

  [Domestic presentation]  精密工学会第31回学生会員卒業研究発表講演会 (東京) , 

  2024.03

  , 

  Oral presentation (general)

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Awards 【 Display / hide 】

Awards 【 Display / hide 】

• JSPE Numata Memorial Paper Award

  T. Hashimoto, J. Yan, 2026.03, The Japan Society for Precision Engineering, Time delay compensation in high-speed diamond turning of freeform surface using independent fast tool servo with a long stroke

  Type of Award： Award from Japanese society, conference, symposium, etc.

• JSME Medal for Outstanding Paper

  L. Zhang, Y. Sato, J. Yan, 2024.04, The Japan Society of Mechanical Engineers, Optimization of fast tool servo diamond turning for enhancing geometrical accuracy and surface quality of freeform optics

  Type of Award： Award from Japanese society, conference, symposium, etc.

• IJEM Best Editor Award

  J. Yan, 2024.01, International Journal of Extreme Manufacturing (IJEM), IoP publishing

  Type of Award： Honored in official journal of a scientific society, scientific journal

• JSPE Best Paper Award

  Lin Zhang, Allen Yi, J. Yan, 2023.03, The Japan Society for Precision Engineering, Flexible fabrication of Fresnel micro-lens array by off-spindle-axis diamond turning and precision glass molding

  Type of Award： Award from Japanese society, conference, symposium, etc.

• 2022 IJEM Best Paper Award

  Y. Sato, J. Yan, 2023.03, International Journal of Extreme Manufacturing (IJEM), IoP publishing, Tool path generation and optimization for freeform surface diamond turning based on an independently controlled fast tool servo

  Type of Award： Honored in official journal of a scientific society, scientific journal

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Courses Taught 【 Display / hide 】

Courses Taught 【 Display / hide 】

• BACHELOR'S THESIS

  2026

• INDEPENDENT STUDIES IN MECHANICAL ENGINEERING

  2026

• MECHANICAL ENGINEERING PRACTICAL RESEARCH A

  2026

• INDEPENDENT STUDY ON INTEGRATED DESIGN ENGINEERING

  2026

• DOCTORAL RESEARCH ON ENGINEERING AND DESIGN

  2026

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Memberships in Academic Societies 【 Display / hide 】

Memberships in Academic Societies 【 Display / hide 】

• The Japan Society of Mechanical Engineers, 

  1997.04

  -

  Present

• The Japan Society for Precision Engineering, 

  1997.04

  -

  Present

• The Japan Society for Abrasive Technology, 

  2000.04

  -

  Present

• Japan Society for Laser Technology (JSLT), 

  2022.01

  -

  Present

• Japan Laser Processing Society (JLPS), 

  2009.01

  -

  Present

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Committee Experiences 【 Display / hide 】

Committee Experiences 【 Display / hide 】

• 2025.03

  -

  Present

  Fellow, Society of Manufacturing Engineers (SME)

• 2024.08

  -

  Present

  Fellow, The International Academy for Production Engineering (CIRP)

• 2024.04

  -

  Present

  Fellow (foreign), The Engineering Academy of Japan (EAJ)

• 2022.04

  -

  Present

  Fellow, The International Society for Nanomanufacturing (ISNM)

• 2022.03

  -

  2026.02

  Director, Executive Director, Chairman of Publication Sector, Chairman of Journal Review Board, Japan Society of Precision Engineering (JSPE)

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