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Experimental study on microstructural evolution, mechanical property, and corrosion behaviour of laser additive manufactured (LAM) titanium alloy grade 5

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INTERNATIONAL JOURNAL OF advanced manufacturing technology 2021年第3-4期114卷 655-669页

作者： Fatoba, Olawale Samuel Jen, Tien-Chien Akinlabi, Esther Titilayo Univ Johannesburg Dept Mech Engn Sci Johannesburg South Africa Pan African Univ Life & Earth Sci PAULESI Ibadan Nigeria

Additive manufacturing technique has become one of the more prominent manufacturing techniques over the years. The applications of this manufacturing technique are boundless as new process parameters of the operation affect the new structure of the components and give extended applications. The study experimentally investigates the effects of Ytterbium Laser System process parameters on the resultant microstructure of Ti-6Al-4V grade 5 alloy and reinforcement powders. The deposition process was conducted employing a 3 kW (CW) Ytterbium Laser System (YLS-2000-TR) machine, co-axial to the reinforcement powder. The laser scanning speed and power were varied between the intervals of 0.8-1.0 m/min and 900-1000 W. All other parameters kept constant were the rate of gas flow, the spot diameter, and the rate of powder flow. The composites (Ti-6Al-4V/Ti-Al-Si-Cu) produced by the DLMD technique were analysed using investigative techniques, namely, optical microscopy (OPM), scanning electron microscopy (SEM) aided with energy dispersive microscopy (EDS), X-ray diffraction analysis (XRD), microhardness testing, and corrosion rate analysis. From the analysis of the physical properties, the findings show that the geometric properties such as heat affected zone (HAZ) and dilution ratio of the composite samples were greatly impacted by the increase of the laser power of the DLMD technique, showing an increase in these attributes brought about by the interaction between the laser and the material. The addition of the copper (Cu) element enabled the movement of the copper (Cu) into the titanium (Ti) lattice structure resulting in the formation of beta titanium (beta-Ti) microstructure. Increment 54.94% is associated with sample 5A which has the most enhanced microhardness of 770 HV1.0. Sample 6A had shown the most corrosion resistance improvement with 0.00062 mm/year equivalent to 31%.

关键词： Geometrical characteristics Additive manufacturing Titanium alloy Microstructures Corrosion rate

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Three-stage deep learning system for recognizing contaminated serial numbers in hard disk drive: A comparison study with two-stage deep learning model 13

Three-stage deep learning system for recognizing contaminate...

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13th International conference on Signal Processing Systems, ICSPS 2021

作者： Chousangsuntorn, Chousak Tongloy, Teerawat Chuwongin, Santhad Boonsang, Siridech Department of Electrical Engineering School of Engineering Faculty of Engineering King Mongkut's Institute of Technology Ladkrabang 10270 Thailand College of Advanced Manufacturing Innovation King Mongkut's Institute of Technology Ladkrabang 10270 Thailand

ISBN: (数字)9781510653184

ISBN: (纸本)9781510653177

The previous two-stage deep learning model for detecting and classifying misidentified serial numbers on the defect hard disk drive (HDD) slider was proposed by authors. We found that the threshold level adjusted during preprocessing process could limit the robustness of the two-stage model in large-scale manufacturing. Thus, we proposed a three-stage deep learning model comprised of 1) region of interest (ROI) detection and cropping, 2) character detection and cropping, and 3) character classification. Object detection algorithm and classification network used in this model are based on YOLO v.4 and EfficientNet-B0. The 1000 images captured by the digital camera were used for training (600 images) and validation (400 images) of the ROI detection model. The other 1000 captured images were used for testing the performance of the proposed three-stage model, then we compared them with those obtained from the previous two-stage model. The proposed three-stage model reaches F1 score = 0.997 and recovery rate up to 95.9%, while the two-stage model yields only 0.948 and 73%, respectively. © COPYRIGHT SPIE.

关键词： Object detection

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Development of a Vision System to Enhance the Reliability of the Pick-and-Place Robot for Autonomous testing of Camera Module used in Smartphones 7

Development of a Vision System to Enhance the Reliability of...

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7th International conference on Engineering and Emerging Technologies (ICEET)

作者： Hoang-Anh Phan Duy Nam Bui Tuan Nguyen Dinh Bao-Anh Hoang An Nguyen Ngoc Dong Tran Huu Quoc Ha Tran Thi Thuy Tung Thanh Bui Van Nguyen Thi Thanh VNU Univ Engn & Technol Res Ctr Elect & Telecommun Hanoi Vietnam VNU Univ Engn & Technol Fac Elect & Telecommun Hanoi Vietnam VNU Univ Engn & Technol Fac Informat Technol Hanoi Vietnam Posts & Telecommun Inst Technol Fac Elect Engn Hanoi Vietnam

ISBN: (纸本)9781665427142

Pick-and-place robots are commonly used in modern industrial manufacturing. For complex devices/parts like camera modules used in smartphones, which contain optical parts, electrical components and interfacing connectors, the placement operation may not absolutely accurate, which may cause damage in the device under test during the mechanical movement to make good contact for electrical functions inspection. In this paper, we proposed an effective vision system including hardware and algorithm to enhance the reliability of the pick-and-place robot for autonomous testing memory of camera modules. With limited hardware based on camera and raspberry PI and using simplify image processing algorithm based on histogram information, the vision system can confirm the presence of the camera modules in feeding tray and the placement accuracy of the camera module in test socket. Through that, the system can work with more flexibility and avoid damaging the device under test. The system was experimentally quantified through testing approximately 2000 camera modules in a stable light condition. Experimental results demonstrate that the system achieves accuracy of more than 99.92%. With its simplicity and effectiveness, the proposed vision system can be considered as a useful solution for using in pick-and-place systems in industry.

关键词： camera modules testing pick-and-place robot computer vision

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316L Stainless Steel Wire Arc Additive manufacturing and Characterization for Potential SNF Canister Production

316L Stainless Steel Wire Arc Additive Manufacturing and Cha...

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2022 International High-Level Radioactive Waste Management conference, IHLRWM 2022, Embedded with the 2022 ANS Winter Meeting

作者： Tang, Wei Giuliano, Dominic Martinez, Oscar Banerjee, Kaushik Nycz, Andrzej Gussev, Maxim Meyer, Luke Vaughan, Derek Materials Science and Technology Division Oak Ridge National Laboratory 1 Bethel Valley Road Oak RidgeTN37831 United States Fusion Energy Division Oak Ridge National Laboratory 1 Bethel Valley Road Oak RidgeTN37831 United States Nuclear Energy and Fuel Cycle Division Oak Ridge National Laboratory 1 Bethel Valley Road Oak RidgeTN37831 United States Manufacturing Science Division Oak Ridge National Laboratory 1 Bethel Valley Road Oak RidgeTN37831 United States

ISBN: (纸本)9780894487897

In this paper, 316L stainless steel (316L SS) straight walls, curved walls, and vessels were printed by wire arc additive manufacturing (WAAM) using the 316L SS welding wire to demonstrate the feasibility of spent nuclear fuel (SNF) canister fabrication using this advanced manufacturing technique. Helium leak tests with a leak-tight criteria of 1 × 10-7 ref-cc/s were performed on the printed vessels with various wall thicknesses. testing pressures ranged from 0.345 MPa (50 psi) to 1.724 MPa (250 psi). Printed wall microstructures were characterized using optical microscopy (OM) and scanning electron microscopy (SEM). Tensile specimens were machined from the printed walls along length, height, and thickness directions and were tested at different temperature conditions, including room temperature and at 80, 150 and 250°C. Results show that all five WAAM-printed canisters with different thickness passed the American National Standards Institute (ANSI) N14.5 helium leak tight criteria for radioactive materials containers. Dispersed micrometer-level size inclusions/voids were observed at the printed wall cross sections, dendritic microstructures were found with grain size variation through the welding torch shifting direction, and very small amounts of δ-ferrite and σ-phase were also observed in those cross sections. The printed walls were ductile, all tensile specimens broke with large plastic deformation/elongation and without brittle failure, and the yield and tensile strengths of the printed specimens at room temperature and 80°C were greater than the minimum values for 316L SS pressure vessels and for general applications at room temperature as required by the ASTM standard, respectively. © 2022 Proceedings of the International High-Level Radioactive Waste Management conference, IHLRWM 2022, Embedded with the 2022 ANS Winter Meeting. All rights reserved.

关键词： 3D printing

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Test of a novel microlens grating based miniature spectrometers array for chromatic confocal technology

Test of a novel microlens grating based miniature spectromet...

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Nanomanufacturing & 4th AET Symposium on ACSM and Digital manufacturing (Nanoman-AETS), International conference on

作者： Jingwen Li Shuonan Shan Peiyuan Liu Jiao Bai Xiaohao Wang Xinghui Li Division of Advanced Manufacturing Shenzhen International Graduate School Tsinghua University Shenzhen China Institute of Materials China Academy of Engineering Physics Mianyang China Tsinghua-Berkeley Shenzhen Institute Tsinghua University Shenzhen China

Multifocal chromatic confocal techniques have important applications in 3D measurement. A chromatic confocal system consists of a dispersive objective, a light source, a fiber coupler, and a spectrometer. An array of spectrometers is required when applying a chromatic confocal sensor for multifocal scanning. A novel microspectrometer array utilizing a single hybrid optical device with microlens array and grating surface on its two sides is developed, which differs from the state-of-the-art micro or miniature spectrometers array usually with a combination use of a microlens arrays a grating. For investigation of feasibility of these microlens array-grating based microspectrometer in multifocal chromatic confocal scanning, we built a chromatic confocal system and test bench, developed an evaluation methodology. testing results demonstrated that the repeatability of detection is in 0.5 pixel. which proves that the microlens grating spectrometer is reliable.

关键词： Three-dimensional displays Wavelength measurement Gratings Reliability Microoptics Lenses optical arrays

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Si含量对316L不锈钢激光熔覆层凝固行为和显微组织的影响

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表面技术 2025年第5期54卷 167-175页

作者：古青包海斌王永强冯敏敏董刚尤涵潇杨高林姚建华国能浙江北仑第一发电有限公司浙江宁波315800 特种装备制造与先进加工技术教育部/浙江省重点实验室杭州310023 浙江工业大学机械工程学院杭州310023 浙江工业大学激光先进制造研究院杭州310023

目的研究Si元素含量对316L不锈钢激光熔覆层凝固行为和显微组织的影响。方法利用LDF400-2000光纤耦合半导体激光器和ABB机械手组成的激光熔覆系统,在316L不锈钢基体上制备Si元素的质量分数分别为0.8%、1.6%的316L激光熔覆层。使用金相... 详细信息

目的研究Si元素含量对316L不锈钢激光熔覆层凝固行为和显微组织的影响。方法利用LDF400-2000光纤耦合半导体激光器和ABB机械手组成的激光熔覆系统,在316L不锈钢基体上制备Si元素的质量分数分别为0.8%、1.6%的316L激光熔覆层。使用金相显微镜、扫描电镜(SEM)、电子背散射衍射(EBSD)、透射电镜(TEM)和维氏硬度计,分别从激光束扫描方向(SD)和切向(TD)分析熔覆层的微观组织、晶粒取向、织构和显微硬度。结果在SD方向,0.8%-Si熔覆层的中下部晶粒呈垂直于底部界面的柱状生长趋势,而顶部晶粒则呈胞状,1.6%-Si熔覆层晶粒的生长模式与0.8%-Si熔覆层类似,但取向更随机。在TD方向,0.8%-Si熔覆层晶粒呈外延状,取向为<100>方向,而1.6%-Si熔覆层则为<111>方向。与0.8%-Si熔覆层相比,1.6%-Si熔覆层内小角度晶界占比更高,超过了50%,在晶粒内部可见被位错缠绕的亚微米颗粒,其硬度也从0.8%-Si熔覆层的199.7HV0.3提升到212.2HV0.3。结论Si元素的含量对激光熔覆316L凝固行为和组织有着显著影响,改变了熔覆层的凝固模式,使组织结构由粗大外延生长的树枝晶转变为沿温度梯度方向生长的细小晶粒。

关键词：激光熔覆 Si元素 316L 凝固组织晶粒细化

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The Effect of Thermal Stress on the Reliability of all-Printed Vias on Flexible Substrates

The Effect of Thermal Stress on the Reliability of all-Print...

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Electronic Components and technology conference (ECTC)

作者： Udara S. Somarathna Mohammed Alhendi Behnam Garakani Mark D. Poliks Darshana L. Weerawarne Joseph Iannotti Christopher J. Kapusta Nancy Stoffel Stephen G. Gonya Center for Advanced Microelectronics Manufacturing The State University of New York Binghamton USA Department of Physics University of Colombo Colombo 03 Sri Lanka GE Global Research Niskayuna New York USA Lockheed Martin Owego New York USA

Reliability of all-printed vias fabricated on flexible polymer substrates is crucial for the proper functionality of flexible hybrid electronics (FHE) which involve interconnected multilayer electronic circuitry. Existing literature primarily focuses on the mechanical reliability of all-printed vias on flexible polymer substrates fabricated by screen printing and inkjet printing techniques. Therefore, in this work, we present new experimental evidence on the reliability of all-printed vias under thermal shock. The details of the fabrication process, optical characterization, and thermal shock testing are discussed in this paper. Two different fabrication process flows were adopted to obtain all-printed partially-filled blind vias and wall-coated through-hole vias. Vias of 50 - 300 μm diameter were laser drilled on a 3-mil polyimide substrate and printed by screen printing and aerosol-jet printing techniques using three types of microparticle- and nanoparticle-based conductive inks of different viscosities. The performance of the all-printed vias was evaluated based on the interlayer electrical connectivity and the change in electrical resistance after exposure to repeated thermal shock cycles. The experimental results show that the all-printed vias are robust and reliable under thermal shock in the temperature (°C) range of -55 to 125.

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Ni-Silicide Schottky Barrier Micropyramidal Photodetector Array

Ni-Silicide Schottky Barrier Micropyramidal Photodetector Ar...

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IEEE National conference on Aerospace and Electronics (NAECON)

作者： Grant W. Bidney Boya Jin Lou Deguzman Joshua M. Duran Gamini Ariyawansa Igor Anisimov Nicholaos I. Limberopoulos Augustine M. Urbas Kenneth W. Allen Sarath D. Gunapala Vasily N. Astratov Center for Optoelectronics and Optical Communications University of North Carolina at Charlotte Charlotte NC USA Air Force Research Laboratory Sensors Directorate OH USA Air Force Research Laboratory Sensors DirectorateOHUSA45433 Air Force Research Laboratory Materials and Manufacturing DirectorateOHUSA45433 Advanced Concepts Laboratory Georgia Tech Research Institute Georgia Institute of Technology Atlanta GA USA Jet Propulsion Laboratory California Institute of Technology Pasadena California USA

ISBN: (纸本)9781665448604

In attempt to increase the quantum yield of metal/silicide Schottky barrier photodetectors, in this work we fabricated and tested Si micropyramidal arrays which are capable to resonantly trap photons in the photodetector areas. To simplify testing, Ni/silicide Schottky barrier photodetectors were formed on the entire $1.5 \times 1.5$ mm areas occupied by the micropyramidal arrays. Preliminary testing results revealed potentially stronger photoresponse of micropyramids with narrow tops, but further studies are required to compare the performance of such novel photodetector arrays with different geometrical parameters of micropyramids.

关键词： conferences Schottky barriers Whispering gallery modes Aerospace electronics Photodetectors Silicon Dielectrics

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Application of micro-course video in optical manufacturing technology 15

Application of micro-course video in optical manufacturing t...

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15th conference on Education and Training in Optics and Photonics (ETOP)

作者： Wang, Shanshan Hao, Qun Huang, Yifan Hu, Yao Wang, Qianqian Zhou, Ya Hui, Mei Song, Yong Beijing Inst Technol Sch Opt & Photon Beijing Key Lab Precis Optoelect Measurement Inst Beijing 100081 Peoples R China

ISBN: (数字)9781510629806

ISBN: (纸本)9781510629806

optical manufacturing technology is a compulsory course for postgraduate and advanced undergraduate majors in optical engineering and similar majors. Modern fabrication and testing equipment are extremely expensive, which cost millions or even tens of millions, and having high requirements for the use environment. Most schools that do not focus on optical fabrication rarely purchase these devices for educational purposes only. Relevant professional teachers are also not familiar with the working principle and use process of the new fabrication and testing equipment such as Computer Controlled optical Surfacing (CCOS), Magnetorheological Finishing (MRF), Ion Beam Figuring (IBF), laser tracker and LuphoScan interferometer. This has caused the teaching content of the course to stay at the stage of singleaxis machining, knife-edge tester, so that students' knowledge of modern equipment is almost blank. While teaching with micro-course videos, the relevant equipment use process can be visually presented to students, and relevant technical experts can also explain the working principle and scope of application to students more professionally. According to the survey, 82% of students like this micro-course video teaching, acknowledging that it helps to better understanding modern optical fabrication and testing equipment, expand students' knowledge, and increase students' advantages in employment competition.

关键词： Micro-course video teaching modern fabrication and testing optical manufacturing technology

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Providing the quality control in manufacturing of optical elements 9

Providing the quality control in manufacturing of optical el...

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conference on optical Design and testing IX

作者： Yan, Wang Zhdanov, Andrey Potemin, Igor S. Zhdanov, Dmitry AW Opt Ltd Peoples St 5988 Changchun 130022 Jilin Peoples R China ITMO Univ 49 Kronverksky Pr St Petersburg 197101 Russia

ISBN: (数字)9781510630888

ISBN: (纸本)9781510630888

optical components are being used more and more extensive in the most areas of production and human life, therefore improving the quality control of optical elements manufacture is high priority task when manufacturing any type of optical element. Every aspect of the production process directly impacts the final product quality and reliability level. In the process of optical elements manufacture, after determining the overall product quality requirements, the next most important thing is to clarify and implement the quality indicators of each product subsystem. So, after the quality requirements of the optical element is determined, the next step that should be done to ensure the quality of final product is measurements and testing work by the professional trained staff. The measurement and test job itself is also a system engineering, because it not only includes the metering and testing hardware (e.g. instruments, equipment, etc.) but also includes software work such as metering management and metering transmission. The quality control of optical components is a process that includes both quality management and the implementation of specific processing and testing methods. optical component processing plants can use the following methods to improve and control the consistency of the quality of the finished optical elements: learn and use new optical component processing techniques, use numerical control technology, use advanced processing and inspection equipment, proficient in process inspection and finished product inspection methods. In this article we present an example of implementation of the quality control phase in the optical elements manufacture process.

关键词： optical elements optics manufacture quality control quality metering lens design

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