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Computer Aided Drafting,Design and Manufacturing 2008年第2期18卷 50-56页

作者： qin Da-hui, SHI Yu-sheng, WANG Cong-jun , LI Zhong-wei (state key laboratory of material processing and die & mould technology, Huazhong University of Science and technology, Wuhan 430074, China)

A new 3D surface contouring and ranging system based on digital fringe projection and phase shifting technique is presented. Using the phase-shift technique, points cloud with high spatial resolution and limited accuracy can be generated. Stereo-pair images obtained from two cameras can be used to compute 3D world coordinates of a point using traditional active triangulation approach, yet the camera calibration is crucial. Neural network is a well-known approach to approximate a nonlinear system without an explicit physical model, in this work it is used to train the stereo vision application system to calculating 3D world coordinates such that the camera calibration can be bypassed. The training set for neural network consists of a variety of stereo-pair images and the corresponding 3D world coordinates. The picture elements correspondence problem is solved by using projected color-coded fringes with different orientations. Color imbalance is completely eliminated by the new color-coded method. Once the high accuracy correspondence of 2D images with 3D points is acquired, high precision 3D points cloud can be recognized by the well trained net. The obvious advantage of this approach is that high spatial resolution can be obtained by the phase-shifting technique and high accuracy 3D object point coordinates are achieved by the well trained net which is independent of the camera model works for any type of camera. Some experiments verified the performance of the method.

关键词： 3D shape measurement color-coded fringe neural network correspondence problem color imbalance

Unraveling the incompatibility mechanism of ethylene carbonate-based electrolytes in sodium metal anodes

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Journal of Energy Chemistry 2024年第7期94卷 560-567页

作者： Daomin qin Fangyuan Cheng Meilian Cao Feiyang Yan Qian Wang Chun Fang Jiantao Han state key laboratory of material processing and die&mould technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan430074HubeiChina

Ethylene carbonate(EC)is widely used in lithium-ion batteries due to its optimal overall performance with satisfactory conductivity,relatively stable solid electrolyte interphase(SEI),and wide electrochemical *** is also the most widely used electrolyte solvent in sodium ion ***,compared to lithium metal,sodium metal(Na)shows higher activity and reacts violently with EC-based electrolyte(NaPF_(6)as solute),which leads to the failure of sodium metal batteries(SMBs).Herein,we reveal the electrochemical instability mechanism of EC on sodium metal battery,and find that the com-bination of EC and NaPF_(6) is electrically reduced in sodium metal anode during charging,resulting in the reduction of the first coulombic efficiency,and the continuous consumption of electrolyte leads to the cell *** address the above issues,an additive modified linear carbonate-based electrolyte is provided as a substitute for EC based ***,ethyl methyl carbonate(EMC)and dimethyl carbon-ate(DMC)as solvents and fluoroethylene carbonate(FEC)as SEI-forming additive have been identified as the optimal solvent for NaFP_(6)based electrolyte and used in Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))/Na *** batter-ies exhibit excellent capacity retention rate of about 80%over 1000 cycles at a cut-off voltage of 4.3 V.

关键词： Na metal batteries Ethylene carbonate decomposition Na_(4)Fe_(3)(PO_(4))_(2)(P_(2)O_(7))cathode Interface engineering Ethylene carbonate-free electrolyte

One-pot synthesis of Li_3VO_4@C nanofibers by electrospinning with enhanced electrochemical performance for lithium-ion batteries

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Science Bulletin 2017年第15期62卷 1081-1088页

作者： Ruihuan qin Gaoqi Shao Junxian Hou Zhi Zheng Tianyou Zhai Huiqiao Li state key laboratory of material processing and die & mould technology School of Materials Science and Engineering Huazhong University of Science and Technology (HUST) Department of Composite materials and Engineering College of Materials Science and Engineering Hebei University of Engineering

Electrospinning is firstly used to one-pot synthesis of Li3VO4@C nanofibers in a large scale. Although with the presence of organic sources in synthesis process, the pure phase Li3VO4 with superior nanofibrous morphology is still successfully obtained through adjusting different heat treatment processes and different vanadium sources. The prepared Li3VO4@C nanofibers exhibit a unique structure in which nanosized Li3VO4 particles are uniformly embedded in amorphous carbon matrix. Compared with LiBVO4/C powder, Li3VO4@C nanofibers display enhanced reversible capacity of 451 mAhg^-1 at 40mAg^-1 with an increased initial coulombic efficiency of 82.3%, and the capacity can remain at 394 mAh g ^-1 after 100 cycles. This superior electrochemical performance can be attributed to its unique structure which ensures a high reactivity by nanosized Li3VO4, more stable electrode/electrolyte interface by carbon encapsulation, improved electronic conductivity and buffered volume changes by flexible carbon matrix. The electrospinning technology provides an effective method to obtain high performance Li3VO4 as a promising anode material for lithium-ion batteries.

关键词： Lithium vanadium oxide Electrospinning Lithium-ion batteries Anode Carbon nanocomposite

Enhanced Dynamic Phase Stability and Suppressed Mn Dissolution in Low-Tortuosity Spinel LMO Electrode

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Energy material Advances 2022年第1期2022卷 24-32页

作者： Renjie He Sheng Lei Mengchuang Liu Mingsheng qin Wei Zhong Shijie Cheng Jia Xie state key laboratory of Advanced Electromagnetic Engineering and technology School of Electrical and Electronic EngineeringHuazhong University of Science and TechnologyWuhan 430074P.R.China state key laboratory of materials processing and die&mould technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China School of Chemistry and Chemical Engineering Huazhong University of Science and TechnologyWuhan 430074China

Microspinel LiMn_(2)O_(4)(LMO)is a widely used cathode material in power lithium-ion ***,inevitable Mn dissolution and dynamic phase instability will cause the degradation of microspinel LMO during ***,a low-tortuosity LMO(LMO-LT)electrode is fabricated by an ice-templating method,which exhibits enhanced dynamic phase stability,alleviated Mn dissolution,and rare particle microcracks during *** is shown that the low-tortuosity electrode enables fast lithium-ion diffusion and thus small concentration polarization,leading to uniform electrochemical reaction within microregions of the LMO-LT ***,the fast lithium-ion transport kinetics and even mesoscopic scale reactions of the LMO-LT electrode effectively alleviate irreversible phase transition and Mn dissolution as well as suppress crack generation in LMO *** a result,the full cell[negative-to-positive capacity ratio(N/P)=1.1]with thick LMO-LT cathode(13 mg cm^(−2))and Li_(4)Ti_(5)O_(12) anode sustains 80.0%capacity over 200 *** LMO-LT electrode further delivers 78.9%capacity of that at 0.1 C at the high rate of 5 *** work provides an important strategy to enhance dynamic phase stability and suppress Mn dissolution at the mesoscopic scale,promoting the development of high-performance LMO electrodes.

关键词： electrode lithium kinetics

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铸造工艺数据驱动的工程机械铸件缺陷预测

铸造 2024年第9期73卷 1329-1335页

作者：刘迎辉余朋潘徐政朱守琴计效园吴来发殷亚军沈旭解明国周建新华中科技大学材料成形与模具技术全国重点实验室湖北武汉430074 安徽合力股份有限公司合肥铸锻厂安徽合肥230022

针对砂型铸造过程缺陷难以寻因、工艺数据类别不平衡问题,提出了一种基于特征重分布与代价敏感学习的卷积神经网络缺陷预测方法。首先,根据样本特征相关性,对特征向量排列顺序进行了优化;其次,基于不平衡工艺数据样本设计了代价敏感正则... 详细信息

针对砂型铸造过程缺陷难以寻因、工艺数据类别不平衡问题,提出了一种基于特征重分布与代价敏感学习的卷积神经网络缺陷预测方法。首先,根据样本特征相关性,对特征向量排列顺序进行了优化;其次,基于不平衡工艺数据样本设计了代价敏感正则项,对模型损失函数进行了修正;最后,构建了缺陷预测模型(FR-CS-CNN)。测试结果表明,本研究构建的FR-CS-CNN在总体预测精度上达到了93.67%,相比卷积神经网络提升了2.96%。

关键词：砂型铸造缺陷预测代价敏感学习卷积神经网络

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Direct observation of dynamic surface reconstruction and active phases on honeycomb Ni_(3)N-Co_(3)N/CC for oxygen evolution reaction

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Science China materials 2022年第9期65卷 2445-2452页

作者： Ping qin Hao Song qingdong Ruan Zhifeng Huang Yue Xu Chao Huang Department of Physics Hong Kong Baptist UniversityKowloon TongKowloonHong Kong SARChina Department of Physics City University of Hong KongTat Chee AvenueKowloonHong KongChina The state key laboratory of Refractories and Metallurgy Institute of Advanced Materials and NanotechnologyWuhan University of Science and TechnologyWuhan 430081China state key laboratory of material processing and die&mould technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China

Oxygen evolution reaction(OER)and hydrogen evolution reaction(HER)are the key processes in water *** with the two-electron process in HER,the four-electron process of OER is slow because of the more complex series of ***,a good understanding of the direct O_(2) evolution mechanism(DOEM)in OER is crucial to design high-efficiency catalysts to overcome the limitations imposed by the conventional adsorption evolution *** this work,honeycomb Ni_(3)N-Co_(3)N was prepared on carbon cloth(Ni_(3)N-Co_(3)N/CC)to investigate the *** functional theory and in situ Raman scattering spectroscopy demonstrated that the OER process on Ni_(3)N-Co_(3)N/CC proceeded via the DOEM pathway,in which Ni_(3)N and Co_(3)N share the roles of dragging OH^(-),splitting off H-O bonds,and adsorbing other OH^(-),leading to significantly reduced Gibbs’s energy barriers of ΔG_(*OH) to ΔG_(O*)and ΔG_(O*)to ΔG_(O*OH).Moreover,the vertical honeycomb structure and conductive CC substrate contributed to the structural stability,conductivity,and quick O_(2) release *** Ni_(3)N-Co_(3)N/CC required low overpotentials of 320 and 495 mV to reach a current density of 10 and 100 mA cm^(-2),***,the Ni_(3)N-Co_(3)N/CC delivered excellent stability with>90% retention of the initial current density over an 80-h-long test.

关键词： oxygen evolution reaction Ni_(3)N-Co_(3)N/CC surface/interface direct O_(2)evolution mechanism

扫描速度和Ni含量对高速激光熔覆层特性的影响

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应用激光 2020年第4期40卷 579-586页

作者：周丹沈义熊大辉王爱华吴旭浩杨志翔武汉华工激光工程有限责任公司湖北武汉430223 华中科技大学材料成形与模具技术国家重点实验室湖北武汉430074 瑞安市激光应用工程示范中心有限公司浙江瑞安325200

本文采用6 kW光纤激光进行了铁基合金高速激光熔覆试验研究,探讨了扫描速度和Ni含量对熔覆层宏观质量的影响,采用金相显微镜表征了高速熔覆层的组织结构特征,采用MM-U10G型磨损试验机和CS350型电化学工作站分别测定了熔覆层的耐磨性和... 详细信息

本文采用6 kW光纤激光进行了铁基合金高速激光熔覆试验研究,探讨了扫描速度和Ni含量对熔覆层宏观质量的影响,采用金相显微镜表征了高速熔覆层的组织结构特征,采用MM-U10G型磨损试验机和CS350型电化学工作站分别测定了熔覆层的耐磨性和耐蚀性。结果表明:通过材料成分和工艺优化,制备的高速激光熔覆层具有良好的宏观质量,表面Ra小于12.5μm,熔覆层无气孔和裂纹等缺陷。不同扫描速度的激光熔覆层显微组织晶粒随着速度的提升而更加细小,组织性能更优。扫描速度700 mm/s时的一次枝晶间距约为速度10 mm/s的1/10,约为速度100 mm/s的1/5。随着Ni含量的增加,熔覆层的硬度虽有所下降,但均大于HV570,耐蚀性均明显优于45钢,在保证一定硬度的前提下,熔覆层可达到与304不锈钢相当的耐蚀性。研究成果在泵阀、轴类零件和牌坊等产品的制造和再制造领域具有广泛的应用前景。

关键词：高速熔覆扫描速度 Ni含量显微组织显微硬度

F-doped O3-NaNi_(1/3)Fe_(1/3)Mn_(1/3)O_2 as high-performance cathode materials for sodium-ion batteries

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Science China materials 2017年第7期60卷 629-636页

作者： qin Zhang Yangyang Huang Yi Liu Shixiong Sun Kun Wang Yuyu Li Xiang Li Jiantao Han Yunhui Huang School of materials Science and Engineering Huazhong University of Science and Technology Wuhan 430074 China

The F-doped O3-type NaNi1/3Fe1/3Mn1/3O2-xFx （x = 0, 0.005, 0.01,002 and noted as NFM-F0, NFM-F0.005, NFM-F0.01, NFM-F0.02, respectively, united as NFM-Fs） cathode materials were investigated systematically. The rate performance and capacity retention of the O3-type cathode materials are significantly improved as a function of specific F-doping levels. Optimum performance is achieved in the NFM-F0.01 material having a capacity of -110mAhg-1 at a current density of 150mAg-1 after 70 cycles. The results indicate that the binding energy of oxygen changes as a result of F-doping, and in addition, F-doping results in changes to the stoichiometry of Mn3＋/Mn4＋, which stabilizes the O3-type layered structure, thus allowing cycling performance to be improved. However, NFM-F0.02, having a higher F-doping level, retains a high capacity retention, although a slight loss is observed. The results suggest there is an optimum F-doping level for the NFM-F system to deliver enhanced cycling performance.

关键词： O3-type NaNi1/3Fe1/3Mn1/3O2 F-doping sodium-ionbatteries

不同铸造工艺下K4169高温合金涡轮机匣凝固组织模拟

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特种铸造及有色合金 2023年第11期43卷 1459-1462页

作者：郭钊秦蓉马鑫李文徐倩中国航发南方工业有限公司华中科技大学材料成形与模具技术国家重点实验室武汉轻工大学机械工程学院

采用凝固组织模拟与试验分析方法,对不同铸造工艺下的K4169合金凝固枝晶溶质扩散、晶粒耦合共晶生长过程进行数值模拟分析,模拟结果与试验结果相符。结果表明,当冷却速率增大时,枝晶生长速率将大于溶质扩散速率,导致枝晶生长末期其周围... 详细信息

采用凝固组织模拟与试验分析方法,对不同铸造工艺下的K4169合金凝固枝晶溶质扩散、晶粒耦合共晶生长过程进行数值模拟分析,模拟结果与试验结果相符。结果表明,当冷却速率增大时,枝晶生长速率将大于溶质扩散速率,导致枝晶生长末期其周围的剩余液相溶质浓度仍将保持在较低水平。在细化剂作用下,铸件凝固过程大量形核,排到液相中的溶质较少,导致在晶粒生长后期剩余的液相溶质浓度仍较低,凝固后的固相溶质浓度也较低,且发生共晶反应的区域较少,抑制了凝固后期析出相数量。

关键词：高温合金铸造工艺凝固模拟元胞自动机

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