检索结果-南通市图书馆

Zirconium-Induced Softening in Hyperstoichiometric Ni_3Al

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2005年第2期21卷 207-210页

作者： Yufang LI, jianting guo and hengqiang YE Institute of metal research, chinese academy of sciences, shenyang 110016, china Inst. of metal Res. Chinese Acad. of Sci. Shenyang 110016 China

The room temperature compressive properties and microhardness of Ni3AI alloys doped with Zr were studied. For the hypostoichiometric Ni3AI alloys, the compressive strength and microhardness increased with an increase in Zr content, while softening behavior induced by doping with a certain amount of Zr was observed in hyperstoichiometric Ni3AI alloy. Possible mechanisms for the softening effect were suggested.

关键词： Ni3Al Compressive properties Microhardness Softening

Tensile Properties and Microstructure of DS NiAl-28Cr-5.8Mo-0.2Hf Alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2002年第2期18卷 181-184页

作者： Chuanyong CUI, jianting guo, Yihui QI and hengqiang yeinstitute of metal research, chinese academy of sciences, shenyang 110016, china [ Manuscript received March 12, 2001, in revised form April 6, 2001] Inst. of metal Res. Chinese Acad. of Sci. Shenyang 110016 China

A multiphase alloy NiAI-28Cr-5.8Mo-0.2Hf was directionally solidified in Ar atmosphere in an Al2O3-SiC2 mold by standard Bridgman method. The fracture toughness and tensile properties at 980℃ as well as tensile creep at 1050℃ were studied. It was found that the strength of the present alloy is higher than that of many NiAI-based alloy and the stress exponent n for creep is about 6.69. Then the possible strengthening mechanism and creep mechanism are also discussed.

关键词： Intermetallic NiAl Microstructure Mechanical properties

Microstructures and Creep Behavior of a Directionally Solidified NiAl-Fe(Nb) Multiphase Intermetallic Alloy

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2003年第1期19卷 59-62页

作者： Yihui QI, jianting guo and Chuanyong GUIDepartment of Superalloys, Institute of metal research, chinese academy of sciences, shenyang 110016, china Dept. of Superalloys Inst. of Metal Res. Chinese Acad. of Sci. Shenyang 110016 China Dept. of Mat. Eng. Liaoning Inst. of Technol. Jinzhou 121001 China

The microstructure and creep behavior of a DS NiAI-Fe(Nb) multiphase intermetallic alloy have been investigated. This alloyexhibits dendritic structure, in which dendritic arm is β-(Ni,Fe)(Fe,Al) phase surrounded by interdendritic region of γ'/γ *** results of the creep test indicated that all of the creep curves have similar characteristic, which is a short primary creepstage and a dominant steady state creep stage, and the creep strain ranges from 18% to 52%. The apparent stress exponentand the apparent activation energy were analyzed and discussed. The mechanism of the creep deformation was also analyzedby the observation of TEM.

关键词： NiAl Multiphase intermetallic alloy Microstructure Creep

Development of a Nickel-base Cast Superalloy with High Strength and Superior Creep Properties

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2005年第3期21卷 347-352页

作者： Jieshan HOU, jianting guo, Lanzhang ZHOU and Zhijun LI Institute of metal research, chinese academy of sciences, shenyang 110016, china Institute of metal research Chinese Academy of Sciences Shenyang 110016 China

Derived from Russian alloy CHS88U, six experimental Ni-base alloys named as A to F in the Ni-Cr-Co-W-Ti-Al-Hf system are designed, evaluated and processed. One of these alloys, F, shows excellent high temperature tensile strength and ductility with superior creep rupture properties. As predicted by using modeling tools such as PHACOM and NEW PHACOMP, there is hardly the tendency for formation of topologically close-packed phase (TCP) phase in alloy F. Furthermore, through microstructural observation, it is also found that no TCP phase is formed in alloy F after long-time exposure at high temperature. So alloy F has well balance of phase stability and mechanical properties in view of application for gas turbines. It is proved that d-electron approach can be applied for design and development of nickel-base superalloys for gas turbine application.

关键词： Conventional Ni-base superalloy Tensile strength Creep life PHACOMP

Formation Mechanism of NiAl/TiB_2 Nanocomposite by Mechanical Alloying Elemental Powders

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 1998年第6期14卷 491-496页

作者： Lanzhang ZHOU and jianting guo(Institute of metal research, chinese academy of sciences, shenyang 110015, china) Institute of metal research Chinese Academy of Sciences Shenyang 110015 China

A NiAl/TiB2 nanocomposite is synthesized by mechanical alloying elemental powders. Upon milling for a certain time, an abrupt exothermic reaction occurs and a large amount of NiAl and TiB2 compounds form simultaneously. It is suggested that two separate chemical reactions,i.e. Ni+Al →NiAl and Ti+2B→TiB2, are involved during the exothermic reaction. Additionof Ti and B to Ni-Al system impedes the structural evolution of Ni and Al powders and delays the abrupt reaction. The final products are equilibrium phases without any metastable phases formed. This type of reaction is suggested to be suitable for alloy systems with two large heatrelease reactions.

关键词： NiAl TiB Formation Mechanism of NiAl/TiB2 Nanocomposite by Mechanical Alloying Elemental Powders

DGConv: A Novel Convolutional Neural Network Approach for Weld Seam Depth Image Detection

在线全文

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第2期78卷 1755-1771页

作者： Pengchao Li Fang Xu Jintao Wang Haibing guo Mingmin Liu Zhenjun du State Key Laboratory of Robotics Shenyang Institute of AutomationChinese Academy of SciencesShenyang110016China Institutes for Robotics and Intelligent Manufacturing Chinese Academy of SciencesShenyang110169China University of chinese academy of sciences Beijing100049China shenyang SIASUN Robot&Automation Co. Ltd.Shenyang110168China

We propose a novel image segmentation algorithm to tackle the challenge of limited recognition and segmentation performance in identifying welding seam images during robotic intelligent ***,to enhance the capability of deep neural networks in extracting geometric attributes from depth images,we developed a novel deep geometric convolution operator(DGConv).DGConv is utilized to construct a deep local geometric feature extraction module,facilitating a more comprehensive exploration of the intrinsic geometric information within depth ***,we integrate the newly proposed deep geometric feature module with the Fully Convolutional Network(FCN8)to establish a high-performance deep neural network algorithm tailored for depth image ***,we enhance the FCN8 detection head by separating the segmentation and classification *** enhancement significantly boosts the network’s overall detection ***,for a comprehensive assessment of our proposed algorithm and its applicability in real-world industrial settings,we curated a line-scan image dataset featuring weld *** dataset,named the Standardized Linear Depth Profile(SLDP)dataset,was collected from actual industrial sites where autonomous robots are in ***,we conducted experiments utilizing the SLDP dataset,achieving an average accuracy of 92.7%.Our proposed approach exhibited a remarkable performance improvement over the prior method on the identical ***,we have successfully deployed the proposed algorithm in genuine industrial environments,fulfilling the prerequisites of unmanned robot operations.

关键词： Weld image detection deep learning semantic segmentation depth map geometric feature extraction

NeurstrucEnergy:A bi-directional GNN model for energy prediction of neural networks in IoT

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Digital Communications and Networks 2024年第2期10卷 439-449页

作者： Chaopeng guo Zhaojin Zhong Zexin zhang Jie Song Software Campus Northeastern UniversityShenyang110000LiaoningChina

A significant demand rises for energy-efficient deep neural networks to support power-limited embedding devices with successful deep learning applications in IoT and edge computing *** accurate energy prediction approach is critical to provide measurement and lead optimization ***,the current energy prediction approaches lack accuracy and generalization ability due to the lack of research on the neural network structure and the excessive reliance on customized training *** paper presents a novel energy prediction model,*** treats neural networks as directed graphs and applies a bi-directional graph neural network training on a randomly generated dataset to extract structural features for energy *** has advantages over linear approaches because the bi-directional graph neural network collects structural features from each layer's parents and *** results show that NeurstrucEnergy establishes state-of-the-art results with mean absolute percentage error of 2.60%.We also evaluate NeurstrucEnergy in a randomly generated dataset,achieving the mean absolute percentage error of 4.83%over 10 typical convolutional neural networks in recent years and 7 efficient convolutional neural networks created by neural architecture *** code is available at https://***/NEUSoftGreenAI/***.

关键词： Internet of things Neural network energy prediction Graph neural networks Graph structure embedding Multi-head attention

Prescribed Performance Tracking Control of Time-Delay Nonlinear Systems With Output Constraints

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

IEEE/CAA Journal of Automatica Sinica 2024年第7期11卷 1557-1565页

作者： Jin-Xi zhang Kai-Di Xu Qing-guo Wang IEEE the State Key Laboratory of Synthetical Automation for Process Industries Northeastern UniversityShenyang 110819China Institute of Artificial Intelligence and Future Networks Beijing Normal UniversityZhuhai 519087 Guangdong Key Laboratory of Artificial Intelligence and Multi-Modal Data Processing Beijing Normal University-Hong Kong Baptist University United International CollegeZhuhai 519087

The problem of prescribed performance tracking control for unknown time-delay nonlinear systems subject to output constraints is dealt with in this paper. In contrast with related works, only the most fundamental requirements, i.e., boundedness and the local Lipschitz condition, are assumed for the allowable time delays. Moreover, we focus on the case where the reference is unknown beforehand, which renders the standard prescribed performance control designs under output constraints infeasible. To conquer these challenges, a novel robust prescribed performance control approach is put forward in this ***, a reverse tuning function is skillfully constructed and automatically generates a performance envelop for the tracking error. In addition, a unified performance analysis framework based on proof by contradiction and the barrier function is established to reveal the inherent robustness of the control system against the time delays. It turns out that the system output tracks the reference with a preassigned settling time and good accuracy,without constraint violations. A comparative simulation on a two-stage chemical reactor is carried out to illustrate the above theoretical findings.

关键词： Nonlinear systems output constraints prescribed performance reference tracking time delays

Preparation and Characterization of Polyaniline Nanofibers by Template-free Method

在线全文

学校读者我要写书评

暂无评论

Journal of Materials Science & Technology 2005年第2期21卷 179-182页

作者： Xuemei guo, Kun LUO and Nanlin SHI Institute of metal research, chinese academy of sciences, shenyang 110016, china Inst. of metal Res. Chinese Acad. of Sci. Shenyang 110016 China

In the presence of p-toluene sulfonic acid (TSA) as a dopant, polyaniline (PAni) nanofibers, (about 80^-65 nm in diameter) were successfully synthesized with a chemical template-free method. It was found that the formation probability, morphology, and diameter of the resulting PAni-TSA nanofibers were sensitive to the synthetic conditions, such as reaction temperature, the molar ratio of TSA to aniline, and the concentration of TSA in the polymerization media. The molecular structure was characterized by using the FT-IR, Raman spectra and X-ray diffraction, which shows that the main chain structure of PAni-TSA nanofibers was in agreement with that of granular PAni.

关键词： Polyaniline p-toluene sulfonic acid Nanoflbers Template-free method