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Effects of copper and zirconium contents on microstructure and magnetic properties of Sm(Co,Fe,Cu,Zr)_(z)magnets with high iron content

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Journal of Rare Earths 2021年第2期39卷 160-166页

作者： Zhifeng Shang Dongtao Zhang Zhihong Xie yunqiao wang Muhammad Haseeb Pengbiao Qiao Weiqiang Liu Ming Yue College of Materials Science and Engineering Key Laboratory of Advanced Functional MaterialsMinistry of Education of ChinaBeijing University of TechnologyBeijing 100124China

The evolution of the microstructure,microchemistry and magnetic properties of the Sm(CobalFe_(0.28)-CuyZrx)_(7.6)magnets with different Zr and Cu contents was *** is found that the coercivity of the Sm(Co,Fe,Cu,Zr)_(z)magnets is sensitive to Zr *** deficiency of Zr content causes heterogeneity of Cu and Fe distributions,while an excessive Zr content leads to the formation of a SmCoZr impurity *** cellular structure and distribution of Cu *** between the cell boundary phase and cell pha se are destroyed by inappropriate Zr content,which results in a reduction of *** Cu concentration difference between the cell boundary phase and cell phase increases with increasing Cu *** coercivity of the Sm(CobalFe_(0.28)CuyZ_(r0.02))_(7.6)magnets increases from 10.4 to 25.4 kOe for y=0.05 and y=***,the excess of Cu element destroys the cell boundary phase and enlarges the cell size,resulting in a significant decrease of squareness and energy *** optimum performance(remanence of 11.4 kG,coercivity of 25.4 kOe,maximum magnetic ene rgy product of 30.4 MGOe)was obtained for the Sm(Co_(0.63)Fe_(0.28)Cu_(0.07)Zr_(0.02))_(7.6)magnet.

关键词： Sm(CoFeCuZr)_(z)permanent magnets Cu Zr Microstructure Magnetic properties Composition distribution

Calcium hydride reduced high-quality Nd-Fe-B powder from Nd-Fe-B sintered magnet sludge

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Journal of Rare Earths 2022年第12期40卷 1905-1912,I0004页

作者： Haibo Xu Qingmei Lu Liying Cong Haowen Tian Weiqiang Liu Youhao Liu yunqiao wang Jingwu chen Xiaofei Yi Ming Yue Key Lab of Advanced Functional Materials Ministry of EducationFaculty of Materials and ManufacturingBeijing University of TechnologyBeijing 100124China State Key Laboratory of Rare Earth Permanent Magnetic Materials Hefei 231500China Earth–Panda Advanced Magnetic Materials Co. Ltd.Hefei 231500China Beijing Zhong Ke San Huan Research Beijing 102200China

The structural and magnetic properties were studied for recycling Nd-Fe-B powders from Nd-Fe-B sintered magnets sludge via reduction diffusion(RD)with calcium hydride(CaH_(2))*** comparison,traditional reducing agent calcium granules were applied to prepare recycled Nd-Fe-B *** particle size and better size distribution as well as lower impurity content are achieved by using CaH_(2)instead of *** detail,the average particle size of the recycled Nd-Fe-B powder is reduced from 4.66 to 3.43μm,and the bimodal distribution ***,the residual calcium content and oxygen content are reduced to about 0.080 wt%and 0.32 wt%.As a consequence,the roomtemperature magnetization of the CaH_(2)-recycled Nd-Fe-B powder is increased to 146.30 emu/g,6.8%and 33%,respectively,higher than that of Ca-reduced powder and the initial *** analysis indicates that CaH_(2)is able to reduce the sludge at lower tempe rature to fabricate well-dispersed,unifo rm recycled powder with high magnetization arising from a combination factors of its low melting point,low thermodynamic behavior,and the release of hydrogen during the reaction.

关键词： Recycled Nd-Fe-B powders Magnetic properties Microstructure Reducing agent Reduction diffusion Rare earths

A facile process to optimize performance of regenerated Nd-Fe-B sintered magnets:Chemo-selective dissolution washing

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Journal of Rare Earths 2023年第12期41卷 1976-1983,I0006页

作者： Haibo Xu Qingmei Lu Lichao Yu Liying Cong Haowen Tian Weiqiang Liu Youhao Liu yunqiao wang Jingwu Chen Xiaofei Yi Qiong Wu Ming Yue College of Materials Science&Engineering Key Lab of Advanced Functional MaterialsBeijing University of TechnologyBeijing100124China Ganjiang Innovation Academy Chinese Academy of SciencesGanzhou341119China State Key Laboratory of Rare Earth Permanent Magnetic Materials Hefei231500China Earth-Panda Advanced Magnetic Materials Co. Ltd.Hefei231500China Beijing Zhong Ke San Huan Research Beijing102200China

In this work,the recycled Nd-Fe-B powders and regenerated Nd-Fe-B sintered magnets with low impurity content were successfully prepared from Nd-Fe-B magnet sludge via reduction diffusion(RD)method followed by a chemo-selective dissolution washing proc *** chemo-selective dissolution effect of various solution(deionized water,dilute acetic acid solution,NH_(4)Cl-methanol solution) was evaluated by impurity content and magnetic properties of the recycled Nd-Fe-B *** NH_(4)Cl-methanol solution can selectively remove impurities with minimal damage to the magnetic ***,the optimal NH_(4)Cl concentration and liquid-to-solid ratio were *** a consequence,the contents of Ca,O,and H after optimal washing process are reduced to 0.07 wt%,0.31 wt% and 0.22 wt%,***,M_(3) Tis increased to 146.72 emu/g,which is 33% higher than that of the initial ***,the regenerated Nd-Fe-B sintered magnets with properties of B_(r)=11.66 kG,H_(cj)=16.49 kOe,and(BH)_(m)=31.78 MGOe were successfully prepared by mixing with 40 wt% Nd4Fe14B alloy *** with the corresponding regenerated magnets washed with deionized water,the remanence and coercivity are increased by 18% and 59%,respectively.

关键词： Recycling Nd-Fe-B magnet Sludge Chemo-selective dissolution Washing process Magnetic properties Reduction diffusion Rare earths

2:17型Sm(CoCuFeZr)_z永磁合金的高性能化研究进展

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稀有金属 2019年第11期43卷 1210-1220页

作者：王云峤岳明北京工业大学材料科学与工程学院新型功能材料教育部重点实验室

2∶17型Sm(CoFeCuZr)z永磁合金因其磁性能良好、居里温度高、温度稳定性强、抗腐蚀和抗氧化性强等优点,满足了航空航天、军事等高温工作环境的使用要求,已成为高温永磁材料的最佳选择。近年来,随着更高使用温度的应用需求和电动车高温... 详细信息

2∶17型Sm(CoFeCuZr)z永磁合金因其磁性能良好、居里温度高、温度稳定性强、抗腐蚀和抗氧化性强等优点,满足了航空航天、军事等高温工作环境的使用要求,已成为高温永磁材料的最佳选择。近年来,随着更高使用温度的应用需求和电动车高温磁体的开发, 2∶17型SmCo永磁体的相关研究重新引起重视。通常,获得较高室温磁性能及高温稳定性的重要因素是拥有高剩磁、高室温矫顽力和低温度系数。相应的,提高磁体磁性能的有效方法主要包括提高Fe含量、优化磁体中Cu元素的含量及分布及掺杂重稀土元素等等。在先前的研究中,主要关注Sm(CoFeCuZr)z磁体晶粒内纳米级的微观结构的演化,鲜有关于磁体晶界研究的报道。本文就Sm(CoFeCuZr)z磁体相关工作在近期取得的进展进行回顾,并介绍了元素含量变化引起的结构、磁性能变化及调控方法,磁体晶界Cu元素分布状态对磁性能的影响方式,以及通过掺杂技术改善Sm(CoFeCuZr)z磁体晶界结构缺陷,最终实现磁体磁性能的优化。

关键词： 2型Sm(CoFeCuZr)z永磁体剩磁矫顽力温度系数重稀土

白细胞计数、C反应蛋白与红细胞沉降率检测在儿童肺炎中的价值分析

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中国基层医药 2020年第22期27卷 2694-2697页

作者：王云桥杭州市儿童医院检验科 310014

目的探讨白细胞计数、C反应蛋白与红细胞沉降率检测在儿童肺炎中的价值。方法选择2017年1月至2018年10月杭州市儿童医院就诊的肺炎患儿100例与行健康体检的健康儿童100例,分别设置为肺炎组、对照组。采集两组受检儿童的空腹静脉血,对血... 详细信息

目的探讨白细胞计数、C反应蛋白与红细胞沉降率检测在儿童肺炎中的价值。方法选择2017年1月至2018年10月杭州市儿童医院就诊的肺炎患儿100例与行健康体检的健康儿童100例,分别设置为肺炎组、对照组。采集两组受检儿童的空腹静脉血,对血液中的白细胞计数、C反应蛋白、红细胞沉降率进行检测,比较肺炎组与对照组、轻症组与重症组、细菌性肺炎组与病毒性肺炎组的白细胞计数、C反应蛋白、红细胞沉降率。采用皮尔逊相关系数分析法,分析白细胞计数、C反应蛋白、红细胞沉降率与肺炎发生、病情严重程度、病因的相关性。结果(1)肺炎组的白细胞计数[(13.56±4.31)×10^9/L]、C反应蛋白[(10.27±4.82)mg/L]、红细胞沉降率[(17.63±5.78)mm/h]均高于对照组(t=10.308、9.012、10.088,均P<0.05)。(2)重症组的白细胞计数[(15.19±2.97)×10^9/L]、C反应蛋白[(11.79±3.14)mg/L]、红细胞沉降率[(19.24±3.20)mm/h]均高于轻症组(t=6.002、5.404、5.460,均P<0.05)。(3)细菌性肺炎组的白细胞计数[(15.31±3.34)×10^9/L]、C反应蛋白[(11.92±3.29)mg/L]、红细胞沉降率[(19.40±3.52)mm/h]均高于病毒性肺炎组(t=4.692、4.685、4.687,均P<0.05)。(4)经相关性分析,白细胞计数、C反应蛋白、红细胞沉降率与肺炎的发生、病情严重程度、病因均存在线性相关,呈正相关。结论肺炎患儿的白细胞计数、C反应蛋白、红细胞沉降率普遍出现异常增高,临床上可通过检测患儿的白细胞计数、C反应蛋白、红细胞沉降率来对肺炎予以辅助诊断,还可用于肺炎的病情评估、疗效判断中。

关键词：儿童肺炎细菌性病毒性白细胞计数 C反应蛋白红细胞沉降率

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飞机铝合金结构件数控加工变形分析与控制

北京航空航天大学学报 2009年第2期35卷 146-150页

作者：梅中义高红王运巧北京航空航天大学机械工程及自动化学院北京100191 成都飞机工业(集团)有限责任公司制造工程部成都610092

以飞机机翼翼肋铝合金结构件这一典型易变形的零件为例,研究数控加工变形情况及其影响因素,主要研究残余应力对加工变形的影响.采用理论建模、有限元分析和实验验证相结合的方法分析和对比数控加工中零件变形情况;分析了工件内残余应力... 详细信息

以飞机机翼翼肋铝合金结构件这一典型易变形的零件为例,研究数控加工变形情况及其影响因素,主要研究残余应力对加工变形的影响.采用理论建模、有限元分析和实验验证相结合的方法分析和对比数控加工中零件变形情况;分析了工件内残余应力分布,用有限元软件提供的热机耦合功能,以温度场模拟施加铝合金的残余应力分布;分析和模拟了去除材料对工件变形的影响;用经过改进的顺序静态单元生死方法进行切削过程的仿真和改进,并对仿真所得的零件变形量与实际加工测量结果进行了比较,验证了分析方法和所建立模型的有效性;最后提出了控制数控加工变形的解决方案.

关键词：数控加工变形残余应力模拟有限元

基于Kinect的人脸表情捕捉及动画模拟系统研究

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图学学报 2016年第3期37卷 290-295页

作者：何钦政王运巧北京航空航天大学机械工程及自动化学院北京100083

三维人脸表情动画技术是一个具有巨大应用前景和研究意义的学科方向。在研究现有表情捕捉和动画合成技术的基础上,提出了一种基于Microsoft Kinect设备的人脸表情动画系统。该系统首先利用Kinect设备捕捉人脸并提取相关表情参数,同时利... 详细信息

三维人脸表情动画技术是一个具有巨大应用前景和研究意义的学科方向。在研究现有表情捕捉和动画合成技术的基础上,提出了一种基于Microsoft Kinect设备的人脸表情动画系统。该系统首先利用Kinect设备捕捉人脸并提取相关表情参数,同时利用Autodesk Maya动画软件建立对应的人脸三维模型,之后将模型导入到OGRE动画引擎并把提取的表情参数传递给OGRE,渲染生成实时人脸表情动画。实验结果表明该技术方案可行,实时表情动画效果达到实际应用水平,相比于现有其他表情动画技术,系统采用通用的Kinect设备,成本更大众化且更容易进行操作。

关键词： Kinect 表情捕捉人脸动画 Maya OGRE

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薄壁弧形件装夹布局有限元优化

机械工程学报 2005年第6期41卷 214-217,223页

作者：王运巧梅中义范玉青北京航空航天大学机械工程及自动化学院北京100083

关于航空结构件加工变形控制的研究是高效数控加工研究的一部分。薄壁弧形零件加工中的弹性变形对加工质量影响很大,而装夹布局影响切削变形的大小和分布。以减少加工中工件最大弹性变形为目标,建立了弧形件铣削加工装夹布局的优化模型... 详细信息

关于航空结构件加工变形控制的研究是高效数控加工研究的一部分。薄壁弧形零件加工中的弹性变形对加工质量影响很大,而装夹布局影响切削变形的大小和分布。以减少加工中工件最大弹性变形为目标,建立了弧形件铣削加工装夹布局的优化模型,采用商业有限元软件的设计优化模块进行计算。在对计算结果进一步分析的基础上,提出了最终的装夹布局方案,采用该方案可以得到整个加工过程中更低的变形量,变形分布更均匀,为采取相应数控补偿措施提供条件。优化方案和实际加工方案结果基本一致。所提出方法可推广至其他类型工件夹具布局优化设计。

关键词：装夹布局加工变形有限元优化

Effects of lanthanum substitution on microstructures and intrinsic magnetic properties of Nd-Fe-B alloy

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Journal of Rare Earths 2015年第9期33卷 961-964页

作者：李智刘卫强查善顺李玉卿王云峤张东涛岳明张久兴 College of Materials Science and Engineering Beijing University of Technology

（Ndl-xLax）30Fe69B （x=0, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6） alloys were prepared by inducting melting, and the effect of substitution of La for Nd on their microstructure and intrinsic magnetic properties were investigated. With the increase of La content, Curie tem- perature （Tc） decreased from 582.4 to 557.4 K, saturation magnetization （Ms） decreased from 1.59 to 1.37 T, and anisotropy field （HA） decreased from 5394 to 3911 kA/m. However, the reductions of the intrinsic magnetic properties were relatively gentle as La content increased, which meant that the intrinsic magnetic properties still had the potential to fabricate permanent magnets. Moreover, further microstructure observations showed that La tended to diffuse into the Nd-rich grain boundary phase instead of main phase during the substitute process. Such aggregation behavior was beneficial to fabricating La containing magnet with high Ms.

关键词： NdFeB alloy: La substitution: microstructure: intrinsic mamaetic orooerties: rare earths