检索结果-内蒙古大学图书馆

Physics guided heat source for quantitative prediction of IN718 laser additive manufacturing processes

npj Computational Materials 2024年第1期10卷 2854-2867页

作者： Abdullah Al Amin Yangfan Li Ye Lu Xiaoyu Xie Zhengtao Gan Satyajit Mojumder Gregory J.Wagner Wing Kam Liu Department of Mechanical Engineering Northwestern UniversityEvanston 60208 ILUSA Department of Mechanical and Aerospace Engineering University of DaytonDaytonOHUSA Department of Mechanical Engineering University of MarylandBaltimore CountyBaltimoreMD 21250USA Department of Aerospace&Mechanical Engineering University of Texas at El PasoEl PasoTXUSA Theoritical and Applied Mechanics Program Northwestern UniversityEvanston 60208 ILUSA

Challenge 3 of the 2022 NIST additive manufacturing benchmark(AM Bench)experiments asked modelers to submit predictions for solid cooling rate,liquid cooling rate,time above melt,and melt pool geometry for single and multiple track laser powder bed fusion process using moving *** in-house developed Additive Manufacturing Computational Fluid Dynamics code(AM-CFD)combined with a cylindrical heat source is implemented to accurately predict these *** heat source calibration is proposed relating volumetric energy density(ψ)based on experiments available in the *** parameters of the heat source of the computational model are initially calibrated based on a Higher Order Proper Generalized Decomposition-(HOPGD)based surrogate *** prediction using the calibrated heat source agrees quantitatively with NIST measurements for different process conditions(laser spot diameter,laser power,and scan speed).A scaling law based on keyhole formation is also utilized in calibrating the parameters of the cylindrical heat source and predicting the challenge *** addition,an improvement on the heat source model is proposed to relate the Volumetric Energy Density(VED_(σ))to the melt pool aspect *** model shows further improvement in the prediction of the experimental measurements for the melt pool,including cases at higher VED_(σ).Overall,it is concluded that the appropriate selection of laser heat source parameterization scheme along with the heat source model is crucial in the accurate prediction of melt pool geometry and thermal measurements while bypassing the expensive computational simulations that consider increased physics equations.

关键词： prediction source additive

来源：评论

学校读者我要写书评

暂无评论

High-Velocity Projectile Impact Behaviour of Friction Stir Welded AA7075 Thick Plates

引用

Defence Technology（防务技术） 2023年第11期29卷 153-163页

作者： R.Praveen S.R.Koteswara Rao G.Selvakumar R.Damodaram Department of Robotics and Automation Karpaga Vinayaga College of Engineering and TechnologyChengalpattu603308TamilNaduIndia Department of Mechanical Engineering Sri Sivasubramaniya Nadar College of EngineeringChennai603110TamilNaduIndia

In this study, high velocity impact behaviour of friction stir welded AA7075-T651 25 mm thick plates were investigated using a 7.62 mm × 51 mm lead core and 7.62 mm × 39 mm steel core projectiles. Prior to ballistic trails, mechanical and metallurgical properties of friction stir welded AA 7075-T651 25 mm thick plates were studied. Microstructural and hardness studies revealed that friction stir welds constituted three distinct regions namely Weld Nugget(WN), Thermo-mechanically Affected Zone(TMAZ) and Heat Affected Zone(HAZ). Base Material(BM) and all three weld regions were ballistically tested as per military standard NIJ.0108.01 using lead and steel core bullets at maximum permissible velocities of 830 ± 20 and 700 ± 30 m/s, respectively. It has been found that base material(AA7075-T651)and all three weld regions of 25 mm thick plates were able to resist perforation by both types of projectiles used. However depth of penetration has been found to increase from BM to WN, HAZ and TMAZ for both types of projectiles. In all cases steel core projectiles caused higher depth of penetration compared to those caused by lead core projectiles. TMAZs of the friction stir welds were found to be the weakest zone. The fracture that occurred in the base material was spall fragmentation indicating brittle failure, whereas all zones of friction stir welded AA7075-T651 targets with a front petalling, indicating ductile failure. The post-ballistic tested samples showed no significant change in the microstructure of the BM and WN. On the other hand, TMAZ and HAZ showed severe grain deformation in the direction of projectile penetration, and the formation of adiabatic shear bands(ASB). This work showed that 25 mm thick friction stir welded AA7075-T651 joints responded well to ballistic impact loads, making them a good choice for light combat vehicles.

关键词： Aluminum alloy Thick plate Friction stir welding Ballistic performance Depth of penetration

来源：评论

学校读者我要写书评

暂无评论

Numerical Analysis of Flat Panel Composite Material for Two-Bay Crack Arrest Competency with Fractured Central Longeron

引用

Journal of The Institution of Engineers (India): Series D 2024年 1-12页

作者： S, Suresh Kumar G, Veeresha Matur, Mahantesh S. R, Aprameya C. Bavan, Saravana Prem Chand, R. B, Manjunatha L, Kumar P. Manjunath, C.J. Department of Mechanical Engineering RV Institute of Technology and Management Karnataka Bengaluru India Department of Mechanical Engineering New Horizon College of Engineering Karnataka Bengaluru India Department of Mechanical Engineering Ramaiah Institute of Technology Karnataka Bengaluru India Department of Mechanical Engineering Government Polytechnic College Karnataka Ballari583101 India Department of Mechanical Engineering Dayananda Sagar University Karnataka Bengaluru560078 India Department of Robotics & amp Artificial Intelligence Bangalore Institute of Technology Karnataka Bengaluru India Department of Mechanical Engineering Bangalore Institute of Technology Karnataka Bengaluru India Department of Mechanical Engineering Atria Institute of Technology Karnataka Bengaluru India

A phenomenon that might cause a structure to collapse catastrophically is the propagation of cracks inside composite materials or at the interface of composite joints. Fail-safe design becomes essential when a structure's integrity is compromised by the element of safety because it has measures that limit failure. This work summarises the research that has been done on these types of crack-arresting features, or CAFs, for metal, composite, and composite laminate joints. Large fatigue cracks are intended to be tolerated in wide-bodied aircraft, and the general damage tolerance design includes two-bay crack arrest capability. In these aircrafts, longeron failure at fuselage crown leads to development of circumferential cracks in the pressurised cabin. The longeron’s capacity to accept load transfer from the cracked skin is what causes these skin cracks to be arrested for two-bay long crack. In direction to create effective damage-tolerant configuration, several parametric studies were carried out, with the longeron being crucial to the safety of circumferential cracks. Using finite element method (FEM) & analysis method, the geometry for longeron was assessed, and it was discovered that Z-Stiffener with larger cross section was more successful in stopping cracks. © The Institution of Engineers (India) 2024.

关键词： Cracks

来源：评论

学校读者我要写书评

暂无评论

Enhancement of Material Properties of AZ80 Mg Alloy Processed by Combined Severe Plastic Deformation

引用

Journal of Bio- and Tribo-Corrosion 2025年第1期11卷 1-12页

作者： Danappa, G.T. Nagaraj, C. Mahesh, K. Dutt Mahantesh, M. Math Rajesh, K. Bavan, Saravana Department of Mechanical Engineering Government Engineering College Karnataka Huvinahadagali583219 India Department of Mathematics Dayananda Sagar Academy of Technology and Management Bangalore560082 India Department of Mechanical Engineering Dayananda Sagar Academy of Technology and Management Bangalore560082 India Department of Mechanical Engineering RV College of Engineering Bengaluru560059 India Department of Robotics and Automation Symbiosis Institute of Technology Symbiosis International [Deemed University Maharashtra Pune422115 India Department of Mechanical Engineering Dyananda Sagar University Bengaluru560068 India

The process of bringing about a novel microstructure can be a good way of improving on the uses of magnesium and its alloys. This study examines the AZ80 Mg with an ultra-fine grain (UFG) that has an average grain size of less than 1 µm by the use of equal channel angular pressing (ECAP), rolling, and multi-direction forged (MDF) processes in combination. The present UFG structure offers better performance characteristic as structural material for Mg alloy. From the as-received state, the AZ80 Mg alloy has better mechanical properties with UTS of 367 MPa and elongation of 16% after the three MDF passes with addition of further two ECAP passes and two passes of rolling. Similarly, the as-received Mg alloy had a corrosion rate of 13.74 mm/y. conventionally, the MDF-3P followed by the ECAP-2P enabled the AZ80 alloy to be improved to 3.69 mm/y. Thus, the corrosion rate has been significantly reduced to 0.95 mm/y using the synergistic treatment of MDF, ECAP, and rolling. © The Author(s), under exclusive licence to Springer Nature Switzerland AG 2024.

关键词： Magnesium alloys

来源：评论

学校读者我要写书评

暂无评论

Dual-compressed photoacoustic single-pixel imaging

引用

National Science Review 2023年第1期10卷 187-195页

作者： Yuning Guo Baowen Li Xiaobo Yin Department of Mechanical Engineering University of Colorado Department of Material Science and Engineering Department of Physics Shenzhen Institute for Quantum Science and Engineering Southern University of Science and Technology Materials Science and Engineering Program University of Colorado

Photoacoustic imaging,an acoustic imaging modality with potentially optical resolution in an optical turbid medium,has attracted great ***,the convergence of wavefront optimization and raster scanning in computational photoacoustic imaging leads to the challenge of fast mapping,especially for a spatial resolution approaching the acoustic deep-subwavelength *** a sparse sampling paradigm,compressive sensing has been applied in numerous fields to accelerate data acquisition without significant quality *** this work,we propose a dual-compressed approach for photoacoustic surface tomography that enables high-efficiency imaging with 3D spatial resolution unlimited by the acoustics in a turbid *** dual-compressed photoacoustic imaging with single-pixel detection,enabled by spatially optical modulation with synchronized temporally photoacoustic coding,allows decoding of the fine optical information from the modulated acoustic signal even when the variance of original photoacoustic signals is *** perform a proof-of-principle numerical demonstration of dual-compressed photoacoustic imaging, that resolves acoustic sub-acoustic-wavelength details with a significantly reduced number of measurements,revealing the potential for dynamic *** dual-compressed concept,which transforms unobtrusive spatial difference into spatio-temporal detectable information,can be generalized to other imaging modalities to re alize efficient,high-spatial-resolution imaging.

关键词： photoacoustic imaging compressive sensing single-pixel imaging surface tomography

来源：评论

学校读者我要写书评

暂无评论

Harnessing the flatbandλ-Ti_(3)O_(5):A breakthrough in solar steam generation

引用

Science China Materials 2023年第11期66卷 4515-4516页

作者： Chuxin Lei Guihua Yu Materials Science and Engineering Program and Walker Department of Mechanical Engineering The University of Texas at AustinAustinTX 78712USA

As global population rises,accompanied by escalating environmental pollution and climate change,numerous countries find themselves grappling with an acute scarcity of natural freshwater resources^([1]).Seawater desalination presents a compelling solution to this looming crisis,especially considering the oceans are Earth’s largest water reservoir^([2]).

关键词： reservoir Earth breakthrough

来源：评论

学校读者我要写书评

暂无评论

Performance Analysis of Re-ID in YOLOv9 and BoT-SORT Algorithm for Multi-object Detection and Tracking

引用

Journal of Institute of Control, robotics and Systems 2025年第2期31卷 160-165页

作者： Young Kim, Sun Ho Kang, Chang School of Mechanical Engineering Kunsan National University Korea Republic of Department of Artificial Intelligence and Robotics Sejong University Korea Republic of

This paper proposes a method for integrating YOLOv9 and BoT-SORT algorithms for multi-object tracking in a multi-camera environment. Particularly, it focuses on analyzing the impact of re-identification (Re-ID) techniques on the overall tracking system performance. Three Re-ID methods-MobileNetV2, OSNet, and OSNet-AIN-are evaluated using the MSMT17 dataset and then applied to the BoT-SORT algorithm to compare multi-object tracking performances. Experimental results show that BoT-SORT with OSNet-AIN achieves the best performance in HOTA, MOTA, and IDF1 metrics. This demonstrates that effective Re-ID techniques can significantly contribute to improving object tracking performance in complex real-world environments. © ICROS 2025.

关键词： Object detection

来源：评论

学校读者我要写书评

暂无评论

mechanical, Microstructure and Tribological Properties of Al–20 wt% Zn Alloy Processed Through As-Cast and Centrifugal Casting

引用

Journal of The Institution of Engineers (India): Series D 2024年第1期106卷 369-382页

作者： Shashikant, G.S. Devaraj, Sonnappa Reddy, B. N. Adarsha Aprameya, C.R. Chand, R. Prem Manjunath, C.J. Vasu, Vikram Kedambadi Department of Mechanical Engineering Akash Institute of Engineering and Technology Bengaluru and Visvesvaraya Technological University Belagavi India School of Mechanical Engineering REVA University Bengaluru India Department of Mechanical Engineering SJC Institute of Technology Visvesvaraya Technological University Belagavi India Department of Mechanical Engineering Government Polytechnic College Karnataka Ballari583101 India Department of Robotics and Artificial Intelligence Bangalore Institute of Technology Karnataka Bengaluru India Department of Mechanical Engineering Atria Institute of Technology Karnataka Bengaluru India Department of Mechanical Engineering Nitte Meenakshi Institute of Technology Karnataka Bengaluru India

Al–20 wt% Zn alloy was As-caste and centrifugal casted, the comparative study of mechanical, microstructure and tribological properties where found. Density of the Al–20 wt% Zn alloy has 2.80 ± 0.0684 gm/cc in centrifugal casting, where it has in as-cast 2.79 ± 0.0403 gm/cc. The chemical composition in alloy are tested in Spark Optical Emission Spectrometer, founds that Al–20 wt% Zn as 82.66% ± 0.0851% of aluminum and 16.82% ± 0.0845% of Zinc. The hardness of alloy in centrifugal is 95.1 ± 6.1 HV1 while in the as-cast is 79 ± 8.3 HV1. Due to centrifugal force in centrifugal casting the grain size and porosity percentage is lower to the as-cast, is found in the optical microscope, the ultimate tensile strength of alloy in as-cast is 214.65 ± 7.903 MPa and in the centrifugal cast is 214.61 ± 12.402 MPa. The wear rate of the alloy in as-cast is 531 µg/Nm in 40N load, speed of 600 rpm and disc diameter of 130 mm while in centrifugal casting is 507 µg/N in 40N load, speed of 400 rpm and disc diameter of 130 mm. The SEM images provided the microstructural abnormalities that will contribute to the failure of alloy in tensile test and the square EDX provided the fully characterize elemental composition of alloy. X-ray diffraction technique is adopted for qualitative analysis of phases in Al–20 wt% Zn alloy for intermetallics formed during As-cast and centrifugal casting. © The Institution of Engineers (India) 2024.

关键词： Porosity

来源：评论

学校读者我要写书评

暂无评论

Investigation of Austempering Effect on Fatigue Crack Growth of AISI 4140 Steel

引用

Defect and Diffusion Forum 2024年 431卷 115-120页

作者： Badaruddin, Mohammad Ainnayah, Reza Annisa Wijaya, Rizqy Nurully Sumardi, Slamet Lampung Selatan Indonesia Department of Mechanical Engineering Faculty of Engineering Universitas Lampung Indonesia Undergraduate Study Program at the Department of M echanical Engineering Faculty of Engineering Universitas Lampung Indonesia

The compact tension (CT) and tensile specimens of the AISI 4140 steel in cold rolling condition (untreated steel) were austempered by immersing it into the salt bath at 362℃ for 60 minutes. The tensile strength properties and the fatigue crack growth (FCG) resistance were performed to investigate the effect of the austempering process in AISI 4140 steel. A significant increase in the yield strength for austempered steel is about 8.7 % and the elastic strain energy increases by 55.7 %. Austempered steel's fatigue crack cycle is longer than that of untreated steel. Data of stress intensity factor range (ΔK, MPa.m1/2) and FCG rate (da/dN, m/cycle) was constructed in double log plot x-y axes for determining the materials constants m and C according to Paris’s law equation using a linear regression method. From the curve of ΔK versus da/dN, the constant m value for austempered steel (m = 3.45) shows better resistance than untreated steel (m = 3.77). On the other hand, the constant C value of 1.409×10-12 for austempered steel is one order magnitude higher than that of untreated steel (C = 4.151×10-13). The resistance of austempered steel against fatigue crack growth can be attributed to the formation of a bainite structure. © 2024 Trans Tech Publications Ltd, Switzerland.

关键词： Stress intensity factors

来源：评论

学校读者我要写书评

暂无评论

Examining the Impact of Metallurgical and Optimised Machining Parameters on Inconel 713C Superalloy Using the Taguchi Technique

引用

Journal of The Institution of Engineers (India): Series D 2024年 1-11页

作者： Suryawanshi, Vinayak P. Deshmukh, Prashant D. Chapke, Yashwant Department of Mechanical Engineering Datta Meghe College of Engineering Airoli Navi Mumbai400708 India Department of Automation & amp Robotics JSPM’S Rajarshi Shahu College of Engineering Maharashtra Pune India

This study examined the metallurgical properties of Inconel 713C superalloy and the impact of utilising the Taguchi technique to optimise machining settings. The cutting tool was a strong carbide substance coated with WC-TiAlN. The impact of cutting force parameters and surface roughness was observed on the Inconel 713C superalloy. The goal of using Taguchi was to maximise the limitations for spinning Inconel 713C alloy at high speeds. An orthogonal array of L27 was used. In order to assess the microstructural and compositional changes, metallurgical tests were conducted. Compared to tool inserts that have not been treated, the EDS scans showed that there is less material deposition on the workpiece. As a result, there was reduced cutting force, friction, and a homogeneous distribution of temperature, which produced a superior surface finish. The workpiece's higher amount of iron, aluminium, and other components, along with the untreated tool, caused localised heating and increased friction. This, in turn, increased cutting force and impacted surface roughness. According to the numerical analysis, the feed rate accounted for up to 95% of the total influence and had the greatest impact on machining performance. © The Institution of Engineers (India) 2024.

关键词： Superalloys

来源：评论

学校读者我要写书评

暂无评论

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案：

请选择收藏分类：

通借通还

建议与咨询 留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

时间限定

文献类型

馆藏选择

核心期刊

语言

文献类型

帮助

文字说明：

检索规则说明：

检索范例：

分类表

所选分类

限定检索结果

文献类型

馆藏范围

日期分布

学科分类号

主题

机构

作者

语言

请选择保存的检索档案： 新增检索档案 确定 取消

请选择收藏分类： 新增自定义分类 确定 取消

通借通还

建议与咨询留下您的常用邮箱和电话号码，以便我们向您反馈解决方案和替代方法

请选择保存的检索档案：

请选择收藏分类：