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Engineering heterogeneous microstructures for enhanced strength and ductility in air-cooled Al−Mg−Si alloys

Transactions of Nonferrous Metals Society of China 2025年第4期35卷 1017-1031页

作者： Yi-han GAO Xin-xin ZHANG Jing-zhe ZHOU Peng XU Zhi-jie XIN Jun-hua GAO Yan-hao SHI You LÜ Yu-fang ZHAO Jing-yang LI School of Aerospace Engineering North University of ChinaTaiyuan 030051China Key Laboratory of Material Chemistry for Energy Conversion and Storage Ministry of EducationHubei Key Laboratory of Material Chemistry and Service FailureSchool of Chemistry and Chemical EngineeringHuazhong University of Science and TechnologyWuhan 430074China R&D Material Division Press Metal International Ltd.Foshan 528137China School of Mechanical Engineering North University of ChinaTaiyuan 030051China

The heterogeneity ofα-Al(Fe,Mn)Si dispersoids andβ″precipitates was tuned to enhance the strength−ductility synergy of air-cooled Al−Mg−Si *** electron microscopy(SEM)and transmission electron microscopy(TEM)were employed to elucidate the microstructural parameters of these two strengthening *** results show that the microstructural heterogeneity can be triggered by the absence of homogenization,resulting in the presence of dispersoid-free zones(dFZs)and dispersoid zones(dZs),in conjunction with bimodalβ″*** analytical calculations,from the strengthening model,clarify that the strategically dispersedα-Al(Fe,Mn)Si andβ″particles create“soft”and“hard”domains within the alloy,resultantly improving the mechanical properties.

关键词： Al−Mg−Si alloy microstructure heterogeneity dispersoid nanoprecipitate mechanical property

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Tensor Flow-Based Capsicum Classification: An Intelligent Mobile Interface Agriculture Crop Monitoring 4

Tensor Flow-Based Capsicum Classification: An Intelligent Mo...

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4th International Conference on Advancement in Electronics and Communication Engineering, AECE 2024

作者： Sudhakaran, Pradeep Yamani, Gajjala Preetha, M. Prema, K. Srm Institute of Science and Technology Department of Computing Technologies Tamil Nadu Kattankulathur603203 India Srm Institute of Science and Technology Career Development Centre Potheri Kattankulathur Tamil Nadu 603203 India Vel Tech Rangarajan Dr.Sagunthala R&d Institute of Science and Technology School of Computing Department of Cse Avadi Tamil Nadu Chennai600062 India

ISBN: (纸本)9798350364729

Utilizing state-of-the-art technologies is essential for effective crop management and monitoring in modern agriculture. The objective of this project is to create a sophisticated mobile interface specifically designed for the classification of bell peppers, or capsicum, in agricultural settings. The main aim of this project is to develop a strong image classification model that can recognize different characteristics of capsicum plants, such as their developmental stage and general health, by using TensorFlow, an open-source machine learning framework. This research uses a methodical approach that begins with gathering and preprocessing a large and varied dataset of labeled photos of capsicums. Subsequently, a convolutional neural network (CNN) is meticulously built and trained using TensorFlow, leveraging transfer learning techniques to enhance the model's functionality. The trained model is transformed into TensorFlow Lite format to enable smooth deployment on mobile platforms. Using a sophisticated image classification model trained on large datasets of tagged photos of capsicums, the main goal is to accurately classify plants according to their growth stages and health status. The project aims to maximize the model's capacity to identify subtle characteristics of capsicum plants by employing transfer learning strategies and pre-trained models. For the project to function smoothly, the trained TensorFlow model must be converted into TensorFlow Lite format. This allows the model to be integrated into an intelligent mobile interface. With the help of this transformation, users can take advantage of an intuitive and mobile-responsive interface to take pictures of capsicum plants in real time with their device's camera. © 2024 IEEE.

关键词： Convolutional neural networks

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Efficient predictive simulation of tool wear in face milling using an advanced 3d numerical approach

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Wear 2025年

作者： Methon, Grégory Courbon, Cédric Auzenat, François M'Saoubi, rachid Girinon, Mathieu rech, Joël Ecole Centrale de Lyon CNRS ENTPE LTDS UMR5513 ENISE 42023 Saint Etienne France R&D Milling and Process Seco Tools AB 22 avenue de la prospective 18020 Bourges France R&D Material and Technology Development Seco Tools AB FagerstaSE-73782 Sweden Cetim 7 rue de la Presse Saint-Etienne42952 France

Being able to predict tool life and the optimal cutting conditions for any combination of cutting tool system and workmaterial is clearly an up-to-date research issue. This work presents an innovative strategy for predicting efficiently tool wear in face milling operations. The primary objective is to develop a methodology capable of handling complex 3d geometries and tool paths within an industrially acceptable computing time. The approach involves a new 3d multi-scale numerical method based on discretizing the tool cutting edge into 2d elementary sections. A 2d Arbitrary Lagrangian-Eulerian (ALE) finite element cutting model is employed to compute local contact pressure, sliding velocity, and heat flux along each section in parallel. An elementary wear equation is applied to calculate the local wear rate after a given time increment, simulating all 2d worn profiles. These profiles are then merged to generate the updated 3d geometry of the worn tool. An iterative procedure is conducted to simulate the evolution of the cutting tool geometry over an extended cutting period. By achieving a good agreement with experimental results in a reasonable computation time, this strategy demonstrates significant potential for optimizing tool life and performance in milling operations. © 2025 Elsevier B.V.

关键词： Milling (machining)

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Laser assisted bonding (LAB) mechanism study on the effect of flux dipping, stage block vacuum force and chip attach misalignment

Laser assisted bonding (LAB) mechanism study on the effect o...

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Electronics Packaging technology Conference (EPTC)

作者： GaHyeon Kim MinHo Gim SeokHo Na WooJun Kim JoHyun Bae dongSu ryu dongJoo Park Kyungrok Park Advanced Process & Material Project Global R&D Center Amkor Technology Korea Inc. Incheon Republic of Korea

In the semiconductor industry, three major bonding technologies are commonly used: mass reflow (Mr, thermocompression bonding (TCB) and laser assisted bonding (LAB). Mr, which is a conventional interconnection method, has been used as a standard for interconnection technology for a long time. However, the limitations of mass reflow from the bump and pad pitch perspective have been predicted for a long time. With Mr it is not easy to make interconnections with very thin die and a coreless substrate and these are major trends in recent packaging structures. Mr has a high warpage, bump tearing due to highest thermal stress. To overcome the mass reflow technical limitation, TCB has appeared to minimize the thermal stress. The TCB process has many advantages such as the lowest thermal stress and the lowest warpage but the weak point of TCB process is very low productivity. With the limitation these two bonding processes, the semiconductor packaging industry focused on the next generation of interconnection technology --- laser assisted bonding. The advantages of the LAB process is a localized heating area that results in lower thermal stress and lower warpage than mass reflow. Also, LAB has very high productivity due to the shortest bonding time. The bonding time of mass reflow is about 5 to 10 minutes but the LAB process is less than 1 second. The comparison of interconnection bonding technologies is summarized in Table *** them, LAB technology has been used for production since 2018 in the industry with technical advantages such as lower thermal budget with localized short heating and lower substrate warpage by stage block vacuum suction, etc. recently, advanced flip chip packaging requires advanced bonding technology. With the industry’s interest in LAB, it will be even more popular. However, at this moment, a better understanding is required of the fundamental bonding *** paper provides the results of studying the LAB bump interconnection mechanism bas

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removing Water Blocking damage in HTHP Tight Gas reservoir Using Alternative Fracturing Fluid

Removing Water Blocking Damage in HTHP Tight Gas Reservoir U...

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2022 SPE Conference at Oman Petroleum and Energy Show, OPES 2022

作者： Liu, Huifeng Zhang, Jianli Liu, Jiangyu Yang, Zhanwei Chen, Tie Gu, Yixin Baletabieke, Bahedaer CNPC Engineering Technology R&D Company Limited China National Oil & Gas Exploration & Development Company China PetroChina Tarim Oilfield Company China Research Institute of Petroleum Exploration and Development PetroChina China

ISBN: (纸本)9781613997062

Tight gas reservoir is easily damaged by liquid phase because of the small pores and throats in the formation. Hydraulic fracturing is usually used in this kind of reservoir to improve well productivity;however, sometimes the productivity declines instead of increasing after treatments because of the damage of the water-based stimulation fluids. This paper introduces a production decline case in the HTHP tight gas reservoir in Tarim Basin, Western China, and provides a new solution. dixi gas reservoir belongs to the formation of Jurassic Ahe Group, with burial depth of about 5000m. The formation porosity is between 3.0-7.0%, and the permeability is less than 0.1md. The average dST production rates of three wells in this area were more than 30×104 m3/d. However, the production declined by 40% after completion. Acidizing and proppant fracturing were both conducted to regain their productivities;however, the production rates were reduced even further after the treatments. One of these wells’ daily production rate declined by 78% compared to dST production after use of acid fracturing and hydraulic fracturing. A series of core flow tests were carried out to find out the causes and solutions. The results showed that the retention of fracturing fluid in the formation caused "water blocking damage", which leaded to a significant increase of water saturation and rapid decline of gas phase permeability. This is considered the main cause of well productivity decline. Therefore, minimizing the capillary force in the formation is considered the main approach to remove the damage. Three series of alternative fracturing fluids were developed and evaluated. The first one is fracturing fluid with methanol. 5%-20% methanol was added to the fracturing fluid to relieve water blocking damage. The results showed that most of the wells fractured by methanol fracturing fluid gained good post-fracturing productivity. Fluorocarbon surfactant fracturing fluid was also developed, in which the

关键词： Fracturing fluids

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3d printed Ultra-High Performance Concrete: Preparation, Application, and Challenges 1

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Nanotechnology in construction, including deep advances in cement chemistry, nanotechnology, artificial intelligence, robotics, concrete technology, and extreme engineering (blast, impact and fire)

作者： Bai, G. Chen, G. Li, r. Wang, L. Ma, G. School of Civil and Transportation Engineering Hebei University of Technology Tianjin China Zhong Dian Jian Ji Jiao Expressway Investment Development Co. Ltd. Shijiazhuang China Yaobai Special Cement Technology R&D Co. Ltd. Xian China

ISBN: (数字)9789819933303

ISBN: (纸本)9789819933297

3d printed ultra-high performance concrete (3dP-UHPC) plays an important role in the realization of ultra-high compressive and tensile strengths. Considering the particular characteristics of UHPC, the conversion of UHPC to 3dP-UHPC is a complex phenomenon and has been the subject of numerous studies. It is very important to be able to design a thixotropic structure in the early hydration stage for bridging the gap between the slow setting of UHPC and the rapid setting of the 3d printing procedure. In the design and application of 3dP-UHPC, requirements such as the ratio of coagulant and flocculant, fiber alignment, reinforced 3d printed no-rebar reinforced concrete, safety, cost etc. need to be taken into account. We present a comprehensive review of 3dP-UHPC in concrete construction from preparation to application, including design method, raw materials, mechanical, reinforced methods, and applications. Finally, recommendations are provided to promote the application of 3dP-UHPC in engineering practice. © 2023, The Author(s).

关键词： 3d printing

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Experimental study of the influencing factors and mechanisms of the pressure-reduction and augmented injection effect by nanoparticles in ultra-low permeability reservoirs

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Petroleum Science 2024年第3期21卷 1915-1927页

作者： Pan Wang Yu-Hang Hu Liao-Yuan Zhang Yong Meng Zhen-Fu Ma Tian-ru Wang Zi-Lin Zhang Ji-Chao Fang Xiao-Qiang Liu Qing You Yan Zhang Beijing Key Laboratory of Unconventional Natural Gas Geological Evaluation and Development Engineering China University of Geosciences(Beijing)Beijing100083China School of Energy Resources China University of Geosciences(Beijing)Beijing100083China Petroleum Engineering Technology Research Institute Sinopec Shengli Oilfield CompanyDongying257000ShandongChina Hekou Oil Production Plant Sinopec Shengli Oilfield CompanyDongying257200ShandongChina Petroleum Exploration and Production Research Institute SINOPECBeijing102206China CNPC Engineering Technology R&D Company Limited Beijing102206China

Nanoparticles(NPs)have gained significant attention as a functional material due to their ability to effectively enhance pressure reduction in injection processes in ultra-low permeability *** are typically studied in controlled laboratory conditions,and their behavior in real-world,complex environments such as ultra-low permeability reservoirs,is not well understood due to the limited scope of their *** study investigates the efficacy and underlying mechanisms of NPs in decreasing injection pressure under various injection conditions(25—85℃,10—25 MPa).The results reveal that under optimal injection conditions,NPs effectively reduce injection pressure by a maximum of 22.77%in core *** pressure reduction rate is found to be positively correlated with oil saturation and permeability,and negatively correlated with temperature and ***,particle image velocimetry(PIV)experiments(25℃,atmospheric pressure)indicate that the pressure reduction is achieved by NPs through the reduction of wall shear resistance and wettability *** work has important implications for the design of water injection strategies in ultra-low permeability reservoirs.

关键词： Nanoparticle Pressure reduction Augmented injection Ultra-low permeability reservoir

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On the wear mechanisms of uncoated and coated pcBN tools during turning of 17–4 PH martensitic stainless steel

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International Journal of refractory Metals and Hard materials 2025年 127卷

作者： Bjerke, A. Casas, J. Lenrick, F. Andersson, J.M. M'Saoubi, r. Bushlya, V. Division of Production and Materials Engineering Lund University Box 118 Lund22100 Sweden R&D Materials and Technology Development Seco Tools AB Fagersta737 82 Sweden

Polycrystalline cubic boron nitride (pcBN) is a very promising tool material for turning martensitic stainless steels at high cutting speeds (vc > 200 m/min). The competitive advantage of pcBN over cemented carbide increases as the cutting speed is increased. Changing the speed might lead to a shift in the wear balance and hence the knowledge about tool wear below vc = 200 m/min might not be applicable at vc = 600 m/min. The coatings designed for the lower speed range might also not be performing in the same way at higher speeds. This paper investigates the wear mechanism of uncoated and (Ti,Al)N coated pcBN tools when turning 17–4 PH in a hardened condition at speeds vc = 200–600 m/min. Both scanning and transmission electron microscopy are used to study the worn tools. The in-depth analysis reveals that adhesive wear is only active at low speeds. Increasing the speed does however lead to more wear by diffusion and oxidation. The cBN is preferentially worn out, leaving the TiC binder at the tool-chip interface. Oxidation results in the accelerated wear of the pcBN but also in the formation of metal oxides within the adhered build up layer. The (Ti,Al)N coating does not significantly extend the tool life within this speed range, but it suppresses the adhesive wear mechanism preventing premature tool failure. © 2024 The Author(s)

关键词： Cubic boron nitride

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Exosomes: Emerging implementation of nanotechnology for detecting and managing novel corona virus-SArS-CoV-2

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Asian Journal of Pharmaceutical Sciences 2022年第1期17卷 20-34页

作者： Akhilesh dubey Cynthia Lizzie Lobo ravi GS Amitha Shetty Srinivas Hebbar Sally AEl-Zahaby Department of Pharmaceutics NGSM Institute of Pharmaceutical SciencesNitte(Deemed to be University)Mangaluru 575018India Formulation and Development Viatris R&D CentreBengaluru 560105India Department of Pharmaceutics and Pharmaceutical Technology Faculty of PharmacyPharos University in AlexandriaAlexandria 21311Egypt

The spread of SArS-CoV-2 as an emerging novel coronavirus disease (COVId-19) had progressed as a worldwide pandemic since the end of 2019. COVId-19 affects firstly lungs tissues which are known for their very slow regeneration. Afterwards, enormous cytokine stimulation occurs in the infected cells immediately after a lung infection which necessitates good management to save patients. Exosomes are extracellular vesicles of nanometric size released by reticulocytes on maturation and are known to mediate intercellular communications. The exosomal cargo serves as biomarkers in diagnosing various diseases;moreover, exosomes could be employed as nanocarriers in drug delivery systems. Exosomes look promising to combat the current pandemic since they contribute to the immune response against several viral pathogens. Many studies have proved the potential of using exosomes either as viral elements or host systems that acquire immune-stimulatory effects and could be used as a vaccine or drug delivery tool. It is essential to stop viral replication, prevent and reverse the massive storm of cytokine that worsens the infected patients’ situations for the management of COVId-19. The main benefits of exosomes could be;no cells will be introduced, no chance of mutation, lack of immunogenicity and the damaged genetic material that could negatively affect the recipient is avoided. Additionally, it was found that exosomes are static with no ability for in vivo reproduction. The current review article discusses the possibilities of using exosomes for detecting novel coronavirus and summarizes state of the art concerning the clinical trials initiated for examining the use of COVId-19 specific T cells derived exosomes and mesenchymal stem cells derived exosomes in managing COVId-19.

关键词： Exosomes COVId-19 Specific T cell-derived exosomes Mesenchymal stem cells-derived exosomes Nanotechnology SArS-Co V-2

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Three-point Bending Test Method Experimental Study for Package Strength and Crack Prediction through Finite Element Analysis

Three-point Bending Test Method Experimental Study for Packa...

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International Conference on (ICEPT) Electronic Packaging technology

作者： Minyan Wu Yunpeng Shang Tingzuo Tan Yonghua Zhou Packaging Technology Development Team Samsung Semiconductor(China)R&D CO. LTD Suzhou China

In recent years with the thinner, smaller, higher-density stack trend for package (PKG) design, the package crack risk becomes higher and higher in the assembly process and reliability tests. Therefore, it is crucial to establish an effective method to measure and predict package strength. The three-point bending (3PB) test is widely used to evaluate package strength. However, detailed parameters of the 3PB test vary among different manufacturers, making it difficult to compare data. Here, the main impact factors and mechanisms were evaluated to demonstrate the impact of 3PB test parameters on data. Additionally, a package strength prediction method was established using ANSYS software and Python based on epoxy mold compound (EMC) fracture. results showed that the placement direction determined how the package crack and internal chips cracked before EMC instead of simultaneous fracture when the indenter was parallel to the package`s long side. Both crack force and strain were changed by more than 20% when one of the indenter sizes, span, or pre-treatment was altered greatly. The effect of speed and strain gage type on the test results was less than 10%. Furthermore, 3PB finite element models were set up, in which boundary setting was solder ball side towards up, short side parallel to indenter, φ0.6mm indenter size, and 12mm span without pre-treatment. The crack force of a typical same-die structure package was predicted through iterations, starting with an initial load value of 100Nton and increments of 5Nton. It was observed that EMC and chips broke simultaneously under the setting test conditions, with the EMC fracture threshold of 130MPa adopted as the criterion for terminating iterations. The highest prediction accuracy of package 3PB strength was 92%, which assists in package crack risk management and provides guidance for future structured design.

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