Article
Engineering, Manufacturing
T. Song, T. Dong, S. L. Lu, K. Kondoh, R. Das, M. Brandt, M. Qian
Summary: This study conducted detailed thermal history simulation for laser metal deposition of Ti-6Al-4V and confirmed the in-situ decomposition of alpha'-martensite during the process, providing insights for process design and microstructural control in additive manufacturing.
ADDITIVE MANUFACTURING
(2021)
Article
Materials Science, Multidisciplinary
Florian Castioni, Sophie Cazottes, Anthony D. Rollett, Sylvain Dancette
Summary: The plastic deformation behavior of alpha' martensite phase in Ti-6Al-4V alloy was investigated through tensile tests in SEM and EBSD analysis, with a focus on the influence of crystallographic orientation on slip modes and the similarity with the alpha phase in terms of identified slip modes. The weighted Schmid analysis using CRSS values of the alpha phase proved effective in describing the behavior of the alpha' phase.
Article
Chemistry, Physical
Zhuohan Cao, Qian Liu, Qianchu Liu, Xiaobo Yu, Jamie J. Kruzic, Xiaopeng Li
Summary: This study develops a machine learning-based approach using image data to predict and reconstruct the microstructural features of LPBF fabricated Ti-6Al-4V alloy. The results show that the proposed method can accurately predict the microstructural features under different process parameters, offering potential applications in process optimization and material design in additive manufacturing.
NPJ COMPUTATIONAL MATERIALS
(2023)
Article
Engineering, Industrial
Z. P. Cui, G. Li, H. Z. Liu, W. J. Zong, H. J. Zhang, C. Y. Zhang, K. Du
Summary: In this study, the wear law of diamond tool in machining of oxygen-free copper is investigated, considering the anisotropy of diamond strength. The cutting stress distribution on the tool face is calculated, revealing higher stress near the flank face. The strength distribution of the tool cutting edge is modeled, indicating significant differences in strength at different positions due to the anisotropy of diamond crystal. The results provide insights into the wear mechanism of diamond tools and facilitate the estimation of tool wear in oxygen-free copper machining.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2023)
Article
Engineering, Multidisciplinary
Senbin Xia, Ziqiang Yin, Jianwen Zhang, Songtao Meng, Yawen Guo, Chen Huang
Summary: This paper introduces a new machining method called Diamond Shifting Cutting (DSC) for fabricating Hexagonal cube corner retroreflectors (HCCRs) and conducts cutting experiments. The experimental results show that this method can effectively produce HCCRs with high precision.
PRECISION ENGINEERING-JOURNAL OF THE INTERNATIONAL SOCIETIES FOR PRECISION ENGINEERING AND NANOTECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
In-Su Kim, Jeong Mok Oh, Sang Won Lee, Jong-Taek Yeom, Jae-Keun Hong, Chan Hee Park, Taekyung Lee
Summary: This study investigated the effects of processing variables on the globularization of AM-processed Ti-6Al-4V alloy, revealing that a combination of solution treatment, low-temperature forging, and subsequent annealing significantly accelerates the process by reducing the path for boundary splitting in fine martensitic laths induced via solution treatment.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Materials Science, Multidisciplinary
Miguel Ruiz de Sotto, Veronique Doquet, Patrice Longere, Jessica Papasidero
Summary: In this study, an extensive experimental campaign and numerical simulations were conducted to investigate the ductile fracture behavior of Ti-6Al-4V titanium alloy. The results showed that ductility of the material exhibited anisotropic characteristics depending on the stress state and strain rate, with different behavior observed in tension and compression. The fracture strain was found to decrease with increasing absolute value of the triaxiality, reaching a maximum close to zero, while no clear correlation with the Lode parameter was identified.
INTERNATIONAL JOURNAL OF DAMAGE MECHANICS
(2022)
Article
Chemistry, Multidisciplinary
Ryotaro Miyake, Hiroyuki Sasahara, Atsushi Suzuki, Seigo Ouchi
Summary: The study investigated the fabrication and finishing of wall-profile machining using wire and arc additive manufacturing with Ti-6Al-4V wire, and examined the possibility of improving machining efficiency by cutting workpieces softened at high temperature. Results showed that although cutting force decreased at high temperature, tool wear rate was high, leading to a significant increase in cutting force due to wear.
APPLIED SCIENCES-BASEL
(2021)
Article
Automation & Control Systems
Berend Denkena, Benjamin Bergmann, Florian Schaper
Summary: Titanium and titanium alloys are widely used in high-performance applications due to their high strength, low density, good corrosion resistance, and excellent biocompatibility. However, they face challenges such as low thermal conductivity, unfavorable chip formation, and chemical interactions with oxygen. This study investigates the chip formation of Ti-6Al-4 V under different cutting speeds and atmospheres, revealing the impact of the surrounding atmosphere on chip formation. It was found that an oxygen-free atmosphere leads to non-periodic segmentation of chips, while air atmosphere leads to segmental chip formation. The use of an oxygen-free atmosphere also reduces friction and lowers the feed force.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Chemistry, Physical
K. Yang, X. Yang, Z. L. Zhang, T. T. Zhu, J. Li, X. S. Xiao, Y. X. Liang, B. Jian, C. Li, S. N. Luo
Summary: The spall damage of Ti-6Al-4V alloy fabricated via laser powder bed fusion (LPBF) was investigated through plate impact in the build direction (BD) and the transverse direction (TD), focusing on its mechanisms and microstructure effects. Comparative analysis was performed on conventionally hot-rolled Ti-6Al-4V alloys processed with annealing and quenching. Results showed that the spall strength and Hugoniot elastic limit (HEL) of LPBF-fabricated samples were higher in the TD loading than in the BD loading. The LPBF-fabricated alloy exhibited a lower HEL but similar spall strength compared to conventionally fabricated alloys. The anisotropy in mechanical properties and damage was attributed to columnar prior beta grains, morphological, and crystallographic texture of martensite laths.
JOURNAL OF ALLOYS AND COMPOUNDS
(2023)
Article
Materials Science, Multidisciplinary
M. Paghandeh, A. Zarei-Hanzaki, H. R. Abedi, Y. Vahidshad
Summary: The study investigates the strain accommodation mechanism of Ti-6Al-4V alloy with different initial microstructures under warm temperature deformation regime. Tensile tests were conducted at various temperatures, revealing different material behaviors and strain accommodation mechanisms in equiaxed alpha+beta, lamellar alpha+beta, dual phase alpha+alpha, and fully alpha martensite microstructures. The results provide insights into the relationship between microstructure, strain accommodation capability, and tensile formability.
JOURNAL OF MATERIALS RESEARCH AND TECHNOLOGY-JMR&T
(2021)
Article
Automation & Control Systems
Paolo Albertelli, Michele Monno
Summary: This study assessed different cooling lubrication approaches for Ti6Al4V milling, finding that cryogenic cutting is less energy demanding and shows better energy performance compared to dry and conventional cutting.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2021)
Article
Engineering, Mechanical
Keke Tang, Kunrong Chen, Paolo Ferro, Filippo Berto
Summary: The effects of lamellar microstructure and microdefects on the fatigue performance of bimodal Ti-6Al-4V have been studied in this paper. A new intragrain weight integration approach was proposed to consider intragranular accumulative deformation, and a parametric accumulative difference indicator was defined to quantify the lamellar microstructural effect. The results have significant implications for the material design and manufacturing of advanced metal alloys.
INTERNATIONAL JOURNAL OF FATIGUE
(2022)
Article
Automation & Control Systems
Junhui Ma, Javad Mohammadi, Yan Zhou, Jeff Larsh, Kris Januszkiewicz, Robert Evans, Yixing Zhao, Olufisayo A. Gali, Reza A. Riahi
Summary: This study investigated the effect of polymer-based and phosphorus-based additives on cutting fluid performance during the drilling of a titanium alloy, showing that different additives had varying effects on the performance under different drilling conditions.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2021)
Article
Materials Science, Multidisciplinary
K. Somlo, K. Poulios, C. Funch, C. F. Niordson
Summary: The study investigates the anisotropic behavior of LPBF Ti-6Al-4V under uniaxial tension through crystal plasticity simulations, which result in a set of crystal plasticity parameters capable of reproducing the experimental behavior. The research demonstrates that the synthetic multi-scale representative volume element and minimized crystal plasticity constitutive parameters can accurately capture the material's Young's modulus, yield strength, and hardening behavior.
MECHANICS OF MATERIALS
(2021)
Article
Engineering, Chemical
Yexiang Fu, Fuwang Zhao, Zejia Zhao, Hui Tang, Suet To, Ching-Hsiang Cheng
Summary: This study reports a method that combines hydrothermal synthesis with ultraprecision machining to fabricate a hierarchical coated surface, improving its hydrophobicity. The experimental results show that the hierarchical surface has a larger contact angle and better water droplet bouncing behavior, indicating excellent water repellency.
JOURNAL OF ADHESION SCIENCE AND TECHNOLOGY
(2023)
Article
Green & Sustainable Science & Technology
Wai Sze Yip, Suet To
Summary: This study combines social network analysis (SNA) and principal component analysis (PCA) to prioritize Ultra-precision machining (UPM) factors based on their combined characteristics. It uses SNA results as input for PCA to generate principal components, which are then combined into multiple characteristic performance indexes (MPCI). Few case studies validate the effectiveness of adjustments in UPM factors with high MPCI on machining outcomes. The study contributes to providing a comprehensive reference for prioritizing UPM factors and developing practical machining strategies.
INTERNATIONAL JOURNAL OF PRECISION ENGINEERING AND MANUFACTURING-GREEN TECHNOLOGY
(2023)
Article
Engineering, Industrial
Yang Yang, Jinqian Xiang, Zejia Zhao
Summary: This paper proposes a novel nano-grating generation mechanism that incorporates the combined effect of shearing-based material removal and compressive forming-based deformation in elliptical vibration texturing. The dynamic cutting force model reveals the transient cutting mechanics and is validated through experiments. The relationship between cutting force characteristics and nano-grating topography is analyzed to guide optimal trajectory designs for high-quality nano-gratings and smaller cutting forces.
JOURNAL OF MATERIALS PROCESSING TECHNOLOGY
(2023)
Article
Materials Science, Multidisciplinary
Zhuoxuan Zhuang, Hanheng Du, Wai Sze Yip, Tengfei Yin, Zejia Zhao, Zhiwei Zhu, Suet To
Summary: In this study, a novel micro and nano-cutting device with complex-axis is developed to overcome the challenge of generating multi-scale cutting motions with high accuracy. The device consists of a customized designed linear voice coil motor and a piezoelectric actuated flexure-hinge mechanism. The device has been optimized using magnetic field simulation and validated through experiments using a force sensor, and it can generate microstructures with high accuracy and flexibility in ultraprecision machining.
MATERIALS & DESIGN
(2023)
Article
Materials Science, Multidisciplinary
Hanheng Du, Zhiwei Zhu, Zuankai Wang, Suet To
Summary: This study proposes a novel piezoelectrically actuated cutting system for fabricating high-aspect-ratio and hierarchical micro/nanostructure arrays. The mechanical structure is designed based on the circular flexure hinge, and a finite element model is established to analyze its resonant frequencies and mode shapes. The effectiveness and flexibility of the proposed cutting system are demonstrated by fabricating micro/nanostructure arrays with varying features.
MATERIALS & DESIGN
(2023)
Article
Engineering, Mechanical
Tengfei Yin, Hanheng Du, Guoqing Zhang, Wei Hang, Suet To
Summary: This paper investigates the formation mechanism of surface waviness in ultra-precision grinding. A dynamics model of the aerostatic bearing wheel spindle is developed to analyze its vibration characteristics. Surface waviness formation models are established considering wheel spindle vibration (WSV) and non-uniform wheel topography (NWT) as the origins of waviness. Grinding experiments are conducted to validate the models. The study provides useful insights for optimizing grinding conditions to enhance surface quality and tribological properties.
TRIBOLOGY INTERNATIONAL
(2023)
Article
Chemistry, Analytical
Xin Li, Yinggang Wang, Hongyu Chen, Wenhong Zhao, Qianfa Deng, Tengfei Yin, Suet To, Zhe Sun, Xi Shen, Wei Hang, Julong Yuan
Summary: In this study, polyurethane, damping cloth, and non-woven fabric were selected as polishing pads. The HPMJ conditioning technology was found to be better than traditional diamond conditioning in terms of keeping the polishing pad surface clean and preventing the hole structure from being blocked. Additionally, the HPMJ conditioned polishing pad had a longer service life and a more stable material removal rate.
Article
Engineering, Manufacturing
Zhanwen Sun, Sujuan Wang, Suet To, Shijun Xu, Guangyu Guo
Summary: Ultra-precision diamond cutting is a promising method for fabricating precision parts of titanium alloys. This study proposes an analytical specific cutting energy (SCE) model that takes into account various factors such as material microstructures, spring back, size effect, cutting edge effect, temperature evolution, and tool-chip frictional states. The results show that the cutting edge effect and spring back contribute to a high SCE at small undeformed chip thickness. The study also suggests an energy-oriented machining parameters optimization method to minimize the SCE in UPDC of titanium alloys.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Article
Automation & Control Systems
Peizheng Li, Sujuan Wang, Suet To, Zhanwen Sun, Jie Jiao, Shijun Xu
Summary: This study proposes a semi-ductile diamond milling method that can produce high-quality microstructured surfaces with high efficiency by fully considering the curvature variation, microstructure geometry characteristics, and machining parameters. By establishing a semi-ductile machining model and the relationship between machining parameters and fragmentation length, determining the dynamically changing tool trajectory, and conducting a comparison experiment, it is demonstrated that the method has high quality and efficiency in creating microstructures on hard and brittle materials.
INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
(2023)
Article
Engineering, Mechanical
Changlin Liu, Suet To, Xuexiang Sheng, Jianfeng Xu
Summary: This paper explores the formation mechanism of crystal defects in single-crystal silicon during elliptical vibration cutting (EVC) using molecular dynamics simulation. The study finds that the cutting stage in EVC greatly influences the surface morphology, including elastic recovery and side flow. The preferred slip motion during subsurface damage formation is distinct in the extrusion and shear stage. The influence of cutting temperature and speed on crystal defects formation is also investigated, revealing the increase in proportion of Shockley partial dislocations at elevated temperature and the suppression of crystal defects generation with higher speed ratio.
INTERNATIONAL JOURNAL OF MECHANICAL SCIENCES
(2023)
Article
Biochemistry & Molecular Biology
C. H. Wong, E. A. Buntov, W. S. Yip, S. To, M. B. Guseva, A. F. Zatsepin
Summary: Through Monte Carlo simulation, we investigated the kink structures in free-standing carbon nanowires under high temperatures. Our study found that short carbon chains exhibit disordered kink structures at high temperatures, which may enhance the chemisorption of negatively charged atoms and provide important insights for the development of high-temperature chemisorption materials.
INTERNATIONAL JOURNAL OF MOLECULAR SCIENCES
(2023)
Article
Engineering, Manufacturing
Pan Guo, Mingyu Liu, Yuanping Zhou, Zhiwen Xiong, Shaojian Zhang, Suet To
Summary: In ultra-precision machining of micro-structured functional surfaces, tool servo dynamic errors, namely tool servo tracking error and tool servo induced vibration, have negative impacts on surface quality. The study reveals two crucial suggestions for improving surface quality: firstly, the tool path should be at least fourth-order differentiable; secondly, the second-order derivative of tool path (required acceleration) should be less than the rated acceleration provided by the tool servo.
JOURNAL OF MANUFACTURING PROCESSES
(2023)
Article
Automation & Control Systems
Yan-Ning Fang, Xiaonan Pu, Suet To, Bernard Hon, Li-Min Zhu, Zhiwei Zhu
Summary: To overcome the limitations of current piezo-actuated triaxial fast tool servos (FTSs), a novel normal-stressed electromagnetic triaxial FTS with a compact structure and high resonant frequency is proposed. It achieves triaxial motions in the range of hundreds of micrometers and utilizes a single armature for decoupled and noncontact driving forces. The prototype of the triaxial FTS shows excellent agreement with the design target in terms of static and dynamic performances. The system is further enhanced with a linear active disturbance rejection control and an iterative learning scheme for fast and accurate trajectory tracking. By fabricating a hexagonal spherical microlens array, the triaxial FTS demonstrates its capability with a high level of spatial accuracy and good surface quality.
IEEE TRANSACTIONS ON INDUSTRIAL ELECTRONICS
(2023)
Article
Chemistry, Multidisciplinary
Changlin Liu, Wai Sze Yip, Suet To, Bolong Chen, Jianfeng Xu
Summary: This article investigates the deformation mechanisms of CdTe during nano-grinding through molecular dynamics (MD) simulation. The results show that the dominant grinding mechanism changes from elastic deformation to ploughing and cutting as the grinding depth increases. The grain size affects the transition from ploughing to cutting and the generation of subsurface damage and dislocations.
Article
Engineering, Chemical
Louis Luo Fan, Wai Sze Yip, Zhanwan Sun, Baolong Zhang, Suet To
Summary: This study investigates the effect of substrate-to-filament distances on coating thickness, diamond purity, coating grain size, and ZrO2 machining performance during HFCVD. The results indicate that smaller substrate-to-filament distances lead to decreased grain size and coating thickness, resulting in improved machining quality for diamond-coated milling tools.
