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International Journal of Minerals,Metallurgy and Materials 2013年第11期20卷 1115-1121页

作者： Shan-jie Yi hai-qing yin Ke Chen Dil-Faraz Khan qing-jun Zheng Xuan-hui Qu School of Materials Science and Engineering University of Science and Technology Beijing Department of Physics University of Science and Technology Bannu Kennametal Inc. 1600 Technology Way Latrobe

Powder injection molding （PIM） and die pressing were employed to fabricate nano-TiN modified Ti（C,N）- based cermets. The shrinkage behavior, microstructure, porosity, and mechanical properties of the samples with and without nano-TiN addition fabricated by PIM and die pressing were analyzed. It is demonstrated that for either PIM or die pressing, the porosities are obviously reduced, the mechanical properties are significantly improved after adding nano-TiN, and the hard particles are refined; the rim phase thickness obviously becomes thinner, and the number of dimples in fracture also increases. Compared the samples fabricated by die pressing, it is difficult for PIM to obtain dense Ti（C,N）-based cermets. Due to the too much existence of pores and isolated carbon, the mechanical properties of the sintered samples by PIM are inferior to those of the sintered ones by die pressing.

关键词： cermets powder injection molding die pressing titanium nitride nanoparticles mechanical properties

Effect of Mn doping on mechanical properties and electronic structure of WCoB ternary boride by first-principles calculations

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Chinese Physics B 2018年第10期27卷 537-547页

作者： Tong Zhang hai-qing yin Cong Zhang Xuan-Hui Qu qing-Jun Zheng Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Beijing 100083 China Beijing Key Laboratory of Materials Genome Initiative University of Science and Technology Beijing Beijing 100083 China Kennametal Inc 1600 Technology Way PA 15650 USA

The first-principles calculations are performed to investigate the structural, mechanical property, hardness, and electronic structure of WCoB with 0, 8.33, 16.67, 25, and 33.33 at.% Mn doping content and W_2 CoB_2 with 0, 10, and 20 at.%Mn doping content. The cohesive energy and formation energy indicate that all the structures can retain good structural stability. According to the calculated elastic constants, Mn is responsible for the increase of ductility and Poisson＇s ratio and the decrease of Young＇s modulus, shear modulus, and bulk modulus. By using the population analysis and mechanical properties, the hardness is characterized through using the five hardness models and is found to decrease with the Mn doping content increasing. The calculated electronic structure indicates that the formation of a B–Mn covalent bond and a W–Mn metallic bond contribute to the decreasing of the mechanical properties.

关键词： Mn doping WCoB electronic structure first-principles calculations

Injection molding and debinding of micro gears fabricated by micro powder injection molding

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International Journal of Minerals,Metallurgy and Materials 2013年第1期20卷 82-87页

作者： Xin-lei Ni hai-qing yin Lin Liu Shan-jie Yi Xuan-hui Qu School of Materials Science and Engineering University of Science and Technology Beijing School of Mechanical and Electrical Engineering China University of Mining and Technology (Beijing)

Micro powder injection molding （μPIM） was investigated for possible mass production of micro-components at rela- tively low cost. However, scaling down to such a level produces challenges in injection molding and debinding. Micro gears were fabricated by μPIM from in-house feedstock. The effect of injection speed and injection pressure on the replication of the micro gear cavity was investigated. Solvent debinding and thermal debinding processes were discussed. The results show that micro gears can be successfully fabricated under the injection pressure of 70 MPa and the 60% injection speed. Either too low or too high injection speed can cause incomplete filling of micro gears. The same is the case with too low injection pressure. Too high injection pressure can bring cracks. Solvent debinding of micro gears was performed in a mixture of petroleum ether and ethanol. Subsequently, micro gears were successfully debound by a multistep heating schedule.

关键词： gear manufacture micro gears injection molding debinding zirconia

The materials data ecosystem： Materials data science and its role in data-driven materials discovery

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Chinese Physics B 2018年第11期27卷 120-125页

作者： hai-qing yin Xue Jiang Guo-Quan Liu Sharon Elder Bin Xu qing-Jun Zheng Xuan-Hui Qu Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Beijing 100083 China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology Beijing Beijing 100083 China Beijing Key Laboratory of Materials Genome Engineering University of Science and Technology Beijing Beijing 100083 China Computer Science and Engineering The Pennsylvania State University University Park PA 16802 USA Kennametal Inc. 1600 Technology Way Latrobe PA 15650 USA Institute of Advanced Materials and Technology University of Science and Technology Beijing Beijing 100083 China

Since its launch in 2011, the Materials Genome Initiative（MGI） has drawn the attention of researchers from academia,government, and industry worldwide. As one of the three tools of the MGI, the use of materials data, for the first time, has emerged as an extremely significant approach in materials discovery. Data science has been applied in different disciplines as an interdisciplinary field to extract knowledge from data. The concept of materials data science has been utilized to demonstrate its application in materials science. To explore its potential as an active research branch in the big data era, a three-tier system has been put forward to define the infrastructure for the classification, curation and knowledge extraction of materials data.

关键词： Materials Genome Initiative materials data science data classification life-cycle curation

A novel approach to predict green density by high-velocity compaction based on the materials informatics method

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International Journal of Minerals,Metallurgy and Materials 2019年第2期26卷 194-201页

作者： Kai-qi Zhang hai-qing yin Xue Jiang Xiu-qin Liu Fei He Zheng-hua Deng Dil Faraz Khan qing-jun Zheng Xuan-hui Qu Collaborative Innovation Center of Steel Technology University of Science and Technology Beijing Beijing Key Laboratory of Materials Genome Engineering Beijing Laboratory of Metallic Materials and Processing for Modern Transportation School of Mathematics and Physics University of Science and Technology Beijing Chongqing Engineering Technology Research Center for Light Alloy and Processing Department of Physics University of Science and Technology Bannu Kennametal Inc

High-velocity compaction is an advanced compaction technique to obtain high-density compacts at a compaction velocity of ≤10 m/s. It was applied to various metallic powders and was verified to achieve a density greater than 7.5 g/cm^3 for the Fe-based powders. The ability to rapidly and accurately predict the green density of compacts is important, especially as an alternative to costly and time-consuming materials design by trial and error. In this paper, we propose a machine-learning approach based on materials informatics to predict the green density of compacts using relevant material descriptors, including chemical composition, powder properties, and compaction energy. We investigated four models using an experimental dataset for appropriate model selection and found the multilayer perceptron model worked well, providing distinguished prediction performance, with a high correlation coefficient and low error values. Applying this model, we predicted the green density of nine materials on the basis of specific processing parameters. The predicted green density agreed very well with the experimental results for each material, with an inaccuracy less than 2%. The prediction accuracy of the developed method was thus confirmed by comparison with experimental results.

关键词： powder metallurgy high-velocity compaction green density data mining multilayer perceptron

Study on the impact force and green properties of high-velocity compacted aluminum alloy powder

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International Journal of Minerals,Metallurgy and Materials 2012年第12期19卷 1107-1113页

作者： Xian-jie Yuan hai-qing yin Rafi-ud Din Dil-faraz Khan Xuan-hui Qu State Key Laboratory for Advanced Metals and Materials University of Science and Technology Beijing Beijing 10083 China School of Materials Science and Engineering University of Science and Technology Beijing Beijing 10083 China

High-velocity compaction （HVC） provides an effective means in the field of powder metallurgy （P/M） to reduce the porosity as well as to ameliorate the mechanical properties of products. In this study, the green density of an aluminum alloy is found to be 2.783 g cm 3. The ejection force for the aluminum alloy is in the range of 23 to 80 kN and the spring back is found to be less than 0.40%. The hardness of the green body is in the range of HRB 30 to 70. The bending strength of the green body is in the range of 6 to 26 MPa, which are higher than that of other aluminum alloys prepared by the traditional compaction method.

关键词： aluminum alloys powders powder metallurgy compaction impact mechanical properties

Machine-learning-assisted prediction of the mechanical properties of Cu–Al alloy

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International Journal of Minerals,Metallurgy and Materials 2020年第3期27卷 362-373页

作者： Zheng-hua Deng hai-qing yin Xue Jiang Cong Zhang Guo-fei Zhang Bin Xu Guo-qiang Yang Tong Zhang Mao Wu Xuan-hui Qu Collaborative Innovation Center of Steel Technology University of Science and Technology BeijingBeijing 100083China Chongqing Engineering Technology Research Center for Light Alloy and Processing Chongqing Three Gorges UniversityChongqing 404000China Beijing Advanced Innovation Center for Materials Genome Engineering Beijing 100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China

The machine-learning approach was investigated to predict the mechanical properties of Cu–Al alloys manufactured using the powder metallurgy technique to increase the rate of fabrication and characterization of new materials and provide physical insights into their *** algorithms were used to construct the prediction models, with chemical composition and porosity of the compacts chosen as the *** results show that the sequential minimal optimization algorithm for support vector regression with a puk kernel(SMOreg/puk) model demonstrated the best prediction ability. Specifically, its predictions exhibited the highest correlation coefficient and lowest error among the predictions of the six models. The SMOreg/puk model was subsequently applied to predict the tensile strength and hardness of Cu–Al alloys and provide guidance for composition design to achieve the expected values. With the guidance of the SMOreg/puk model, Cu–12Al–6Ni alloy with a tensile strength(390 MPa) and hardness(HB 139) that reached the expected values was developed.

关键词： powder metallurgy tensile strength hardness machine learning Cu–Al alloy SMOreg/puk

Molecular identification and interaction assay of the gene(OsUbc13) encoding a ubiquitin-conjugating enzyme in rice

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2014年第7期15卷 624-637页

作者： Ya WANG Meng-yun XU Jian-ping LIU Mu-gui WANG hai-qing yin Ju-min TU Institute of Crop Science College of Agriculture and Biotechnology Zhejiang University Cereal Crops Institute Henan Academy of Agricultural Sciences

The ubiquitin （Ub）-conjugating enzyme, Ubc13, has been known to be involved in error-free DNA damage tolerance （or post-replication repair） via catalyzing Lys63-linked polyubiquitin chains formation together with a Ubc variant. However, its functions remain largely unknown in plant species, especial y in monocotyledons. In this study, we cloned a Ub-conjugating enzyme, OsUbc13, that shares the conserved domain of Ubc with AtUBC13B in Oryza sativa L., which encodes a protein of 153 amino acids; the deduced sequence shares high similarities with other homologs. Real-time quantitative polymerase chain reaction （PCR） indicated that OsUbc13 transcripts could be de-tected in al tissues examined, and the expression level was higher in palea, pistil, stamen, and leaf, and lower in root, stem, and lemma;the expression of OsUbc13 was induced by low temperature, methylmethane sulfate （MMS）, and H2O2, but repressed by mannitol, abscisic acid （ABA）, and NaCl. OsUbc13 was probably localized in the plasma and nuclear membranes. About 20 proteins, which are responsible for the positive yeast two-hybrid interaction of OsUbc13, were identified. These include the confirmed OsVDAC （correlated with apoptosis）, OsMADS1 （important for development of floral organs）, OsB22EL8 （related to reactive oxygen species （ROS） scavenging and DNA protection）, and OsCROC-1 （required for formation of Lys63 polyubiquitylation and error-free DNA damage tolerance）. The molecular characterization provides a foundation for the functional study of OsUbc13.

关键词： Ubc13 DNA damage tolerance Oryza sativa Real-time quantitative PCR Yeast two-hybrid

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基于MST雷达垂直风速的大气温度剖面反演

物理学报 2014年第9期63卷 194-200页

作者：青海银张援农周晨赵正予陈罡武汉大学电子信息学院空间物理系武汉430072

本文主要利用MST(mesosphere-stratosphere-troposphere)雷达垂直风速时间序列进行频谱分析,计算B-V(Brunt-V?is?l?)频率,再根据B-V频率和温度的关系,本文建立了离散的温度反演模型,最后反演得到了全高度的温度剖面.通过计算温度剖面和... 详细信息

本文主要利用MST(mesosphere-stratosphere-troposphere)雷达垂直风速时间序列进行频谱分析,计算B-V(Brunt-V?is?l?)频率,再根据B-V频率和温度的关系,本文建立了离散的温度反演模型,最后反演得到了全高度的温度剖面.通过计算温度剖面和探空仪实测温度剖面比较可见,二者的符合度非常高,变化趋势也完全一致.本文还进一步讨论了,利用B-V频率和MST雷达的水平风速还可以计算理查德森数,通过理查德森数可以很清晰的判断大气的稳定性,进而可以量化大气很多动力学特征以及解释大气中的很多波动现象.因此,B-V频率的获得是MST雷达对大气动力学研究的又一贡献,它可以准确地反演大气的温度剖面,同时获取大气动力学稳定性参数.

关键词：大气温度 mesosphere-stratosphere-troposphere(MST)雷达 Brunt-Vaisala(B-V)频率理查德森数

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基于武汉MST雷达的对流层顶观测研究

地球物理学进展 2018年第4期33卷 1395-1402页

作者：青海银赵正予周晨乐山师范学院、物理与电子工程学院四川乐山614000 武汉大学、电子信息学院空间物理系武汉430072

基于无线电探空仪和掩星的对流层顶观测虽然可以揭示对流层顶高度和温度的一些特性,但是在某一个地点的时间分辨率较低,资料的时间分辨率几乎都是以天计,同时所获得的对流层顶信息也不能直接反映对流层顶的产生、发展和消亡过程.借助于... 详细信息

基于无线电探空仪和掩星的对流层顶观测虽然可以揭示对流层顶高度和温度的一些特性,但是在某一个地点的时间分辨率较低,资料的时间分辨率几乎都是以天计,同时所获得的对流层顶信息也不能直接反映对流层顶的产生、发展和消亡过程.借助于MST雷达具有高时间分辨率和连续性这一显著优势,实时、连续地获得对流层顶雷达回波,通过构建普适性雷达对流层顶判读模型,可以更好地研究对流层顶高度和结构形态的时空演化过程.探空仪对比实验表明:雷达方法观测对流层顶高度与气象学方法观测对流层顶高度相差约2 km,这应该和二者的探测机制相关.统计分析2012年全年雷达对流层顶回波差异值可以发现,雷达对流层顶高度的年平均值为13.3 km,标准差为0.65 km;对流层顶回波差异平均值约为11.7 d B,标准差为4.3 d B,雷达对流层顶回波差异值直接反映了雷达对流层顶结构的稀疏状态.同时本文利用Lomb-Scargle谱分析方法检测了对流层顶结构形态的扰动周期,结果表明大气潮汐波和行星波分量会影响对流层顶的结构形态.

关键词： MST雷达对流层顶潮汐波行星波