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液氮球磨制备Sm-Fe合金粉末及其微观组织研究

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液氮球磨制备Sm-Fe合金粉末及其微观组织研究

微型器件飞秒激光加工参数对切缝坡度影响规律的实验研究

全国博士后微纳米粉体与材料应用技术交流会

作者：崔向中杨滨邱晓锋北京科技大学新金属材料国家重点实验室

利用液氮球磨技术制备了Sm-Fe合金粉体。采用SEM、HRTEM、XRD以及XPS等方法对SmFe合金在液氮球磨过程中的微观组织演变过程及球磨机制进行了研究。结果表明:随着球磨时间延长,SmFe合金在液氮球磨过程中物相结构被破坏,Sm-Fe相出现非晶化... 详细信息

利用液氮球磨技术制备了Sm-Fe合金粉体。采用SEM、HRTEM、XRD以及XPS等方法对SmFe合金在液氮球磨过程中的微观组织演变过程及球磨机制进行了研究。结果表明:随着球磨时间延长,SmFe合金在液氮球磨过程中物相结构被破坏,Sm-Fe相出现非晶化,并且有少量的氮化物生成。与常温球磨相似,球磨过程包括破碎、冷焊、再破碎,材料的颗粒度随着球磨过程的进行,呈现先减小再稍有增大然后再减小的趋势,并且当球磨时间达到一定程度时,颗粒度保持动态稳定,球磨9 h后,颗粒尺寸保持在1～3μm之间;但相对于常温球磨,球磨时间明显缩短,并且冷焊作用表现得非常不明显。晶粒尺寸随着球磨时间的延长逐渐减小,球磨5 h时,晶粒尺寸约为10 nm,9 h后晶粒尺寸约为5 nm。随着球磨时间的延长,Sm-Fe合金中氮含量增加,氧含量并无明显的变化,球磨9h后,氮含量达1.23wt%。

关键词： Sm2Fe17合金液氮球磨非晶氮化

来源： cnki会议评论

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应用激光 2017年第5期37卷 693-697页

作者：李元成张伟张晓兵崔向中北京航空制造工程研究所高能束流加工技术重点实验室北京100024

利用飞秒激光在铝箔上按设定好的轮廓程序重复扫描直至切透得到所需轮廓的微型器件,研究了飞秒激光加工参数对切缝边缘坡度的影响规律。实验结果表明,透镜焦距、扫描速度和飞秒激光能量密度与切缝坡度密切相关。切缝坡度随着扫描速度的... 详细信息

利用飞秒激光在铝箔上按设定好的轮廓程序重复扫描直至切透得到所需轮廓的微型器件,研究了飞秒激光加工参数对切缝边缘坡度的影响规律。实验结果表明,透镜焦距、扫描速度和飞秒激光能量密度与切缝坡度密切相关。切缝坡度随着扫描速度的增大而增大,随着能量密度和聚焦透镜焦距的增大而逐渐减小。实验中飞秒激光切透大块铝箔材料即微型器件脱落时停止出光,切缝未能继续发育,坡度主要由材料上表面切割缝宽决定,与飞秒激光高斯能量分布特征和去除材料的阈值密切相关。

关键词：飞秒激光微器件坡度加工参数

Preparation of BaMgAl_(10)O_(17):Eu^(2+) and Its Phase Behavior in Microemulsion System

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Journal of Rare Earths 2006年第6期24卷 736-739页

作者：张熙莹庄卫东崔向中何华强黄小卫 National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co. Ltd. Beijing 100088China

BaMgAl10O17 ： Eu^2＋（BAM） was prepared in the microemulsion system and its phase behavior was studied. There exists a small region in the reverse microemulsion system where the dispersed particles are of spherical form. In this way, BAM blue phosphor with good dispersion can be synthesized. The microemulsion phase diagrams of the pseudo-ternary system （Triton X-100/cosuffactant-oil-BAM brine） were first established intuitively by the dilution method. The microstructure of microemulsions was determined through eyeballing, conductance technique, and polar optical microscopy. Its phase behavior is affected by various factors, such as temperature （room temperature, 30, 40 ℃）, oil, surfactants, and cosurfactants in microemulsions. According to the phase diagrams, the microemulsion system of Triton X-100/1-hexanol-hexane-BAM brine was chosen to prepare the precursor. The BAM phosphor can be obtained via sintering the precursor at a comparatively low temperature. The phosphors were characterized by XRD and vacuum ultraviolet （VUV） spectra.

关键词： microemulsion surfactant phase diagram BAM rare earths

基体温度对TC11钛合金EB-PVD修复层组织及振动疲劳寿命的影响

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中国表面工程 2015年第2期28卷 59-64页

作者：孙刚陈学明马国佳马江宁崔向中北京航空制造工程研究所高能束流加工重点实验室北京100024 国营锦江机器厂成都610043

为了研究温度对修复层性能的影响,采用电子束物理气相沉积（EB-PVD）技术在TC11平板试样上制备了修复层,利用X射线衍射仪（XRD）、扫描电子显微镜（SEM）和能谱仪（EDS）研究了不同温度下修复层的成分及组织形貌变化,并通过振动疲劳试... 详细信息

为了研究温度对修复层性能的影响,采用电子束物理气相沉积（EB-PVD）技术在TC11平板试样上制备了修复层,利用X射线衍射仪（XRD）、扫描电子显微镜（SEM）和能谱仪（EDS）研究了不同温度下修复层的成分及组织形貌变化,并通过振动疲劳试验等方法研究了温度对修复层振动疲劳寿命的影响。结果表明：在600~800℃进行修复时,修复层为柱状晶组织。修复层的致密性随温度升高而变大,这种变化也会影响修复后试片的振动疲劳性能,修复层柱状晶结构间隙处形成的裂纹源会造成试片疲劳性能的下降。

关键词：电子束物理气相沉积(EB-PVD) 温度修复层振动疲劳寿命

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航空表面涂层技术的应用与发展

航空制造技术 2016年第14期59卷 32-36,46页

作者：李其连崔向中中航工业北京航空制造工程研究所高能束流加工技术重点实验室北京100024

航空表面涂层技术是航空制造技术的重要组成部分,涂层材料与涂层制造技术创新对提高航空零部件产品性能、降低能源消耗、提升产品可靠性及服役寿命具有重要意义。主要对涉及航空工业领域热障涂层、复合材料表面环境障涂层、高温可磨耗... 详细信息

航空表面涂层技术是航空制造技术的重要组成部分,涂层材料与涂层制造技术创新对提高航空零部件产品性能、降低能源消耗、提升产品可靠性及服役寿命具有重要意义。主要对涉及航空工业领域热障涂层、复合材料表面环境障涂层、高温可磨耗封严涂层及纳米涂层技术的应用现状与研究进展进行了阐述。

关键词：航空涂层技术热障涂层环境障涂层封严涂层纳米涂层

采用EB-PVD技术制备两种多分层热障涂层的研究

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材料导报 2012年第20期26卷 21-24页

作者：刘亮张华芳高巍雷新更崔向中郑玉峰哈尔滨工程大学生物医用材料与工程研究中心哈尔滨150001 中航工业北京航空制造工程研究所高能束流加工技术重点实验室北京100024 北京大学工学院北京100871

基于电子束物理气相沉积(EB-PVD)技术,设计并分别采用离子束辅助沉积法和低转速法制备了两种具有分层结构的热障涂层(TBCs),对陶瓷层引入层状结构后的组织结构与性能进行了研究。结果表明,层状结构的引入带来大量平行于沉积面的分层界... 详细信息

基于电子束物理气相沉积(EB-PVD)技术,设计并分别采用离子束辅助沉积法和低转速法制备了两种具有分层结构的热障涂层(TBCs),对陶瓷层引入层状结构后的组织结构与性能进行了研究。结果表明,层状结构的引入带来大量平行于沉积面的分层界面和相邻分层间的密度调制变化。层状结构TBCs的占优取向由(100)逐渐变化到(111),但仍都形成了不可转变的四方相(t′)结构。依据分层结构本身的差异和分层界面所处位置的不同,低转速分层试样具有更好的抗氧化性能,但离子辅助分层试样具有明显更长的热循环寿命。

关键词：热障涂层离子束辅助沉积多层寿命

Low Temperature Luminescence Properties of Tm^(3+) Doped Aluminate Phosphor

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Journal of Rare Earths 2006年第z2期24卷 141-144页

作者：夏天庄卫东崔向中赵春雷滕晓明黄小卫 National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metalsand Grirem Advanced Materials Co. Ltd.

(Ba0.66Sr0.33)Mg0.8Al11.47O19:Tm0.013+(BSMA:Tm3+ ) phosphor was synthesized by solid-state reactions. The sample was characterized by X-ray diffraction (XRD), scanning electronic microscope (SEM), vacuum ultraviolet (VUV) spectra, ultraviolet (UV) spectra and FT-IR spectrum. XRD pattern reveals that BSMA: Tm3 + has the same structure as BaAl12O19 phase. SEM image illustrates that the phosphor has the hexagonal shape and deep slice structure. VUV and UV emission spectra at 20, 50 and 100 K show that the low temperature luminescence intensities become weak gradually with the increasing of the temperature under 147 and 254 nm excitation. The strong broadband peaks at around 357 and 397 nm and the peak at 516 nm under 147 nm excitation all correspond to the characteristic transitions of Tm3 + ions. However, under UV (254 nm) excitation, the main peak becomes 530 nm which has very high line intensity, and the peaks at about 362 and 403 nm are very weak. The excitation spectrum at 20 K shows that there are three absorption peaks at around 153, 186 and 193 nm when 516 nm emission is monitored. The absorption peaks of [AlO4], [AlO6] and Al-0 can be observed in FT-IR spectrum.

关键词： vacuum ultraviolet low temperature luminescence Tm3+ ion rare earths

Luminescent Properties of BaMgAl_(10)O_(17)∶Eu^(2+) Phosphors Coated with Y_2SiO_5

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Journal of Rare Earths 2006年第2期24卷 143-145页

作者：滕晓明庄卫东黄小卫崔向中张书生 National Engineering Research Center for Rare Earth Materials General Research Institute for Nonferrous Metals Grirem Advanced Materials Co. Ltd. Beijing 100088 China National

BaMgAl10O17： Eu^2＋ phosphors was prepared by the solid-reaction method. Y2SiO5 was coated uniformly on the surface of phosphor by the surface-coated method, and the luminescent and deterioration properties were discussed. The XRD and SEM results show that Y2SiO5 film is produced on the surface of BAM phosphor. The emission spectrum analysis shows that the peak of the phosphor does not change after coating. The two phosphors were applied to lamps and the deterioration was tested at different ignited time. The keep ratio of luminous flux of the phosphor coated with Y2SiO5 is higher than that of the uncoated phosphor.

关键词： BAM coat Y2SiO5 deterioration rare earths

Co-Precipitation Preparation and Luminescent Behavior of(Y,Gd)BO_3∶Eu Phosphor

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Journal of Rare Earths 2004年第6期22卷 829-832页

作者：鱼志坚黄小卫庄卫东崔向中何华强李红卫 National Engineering Center for Rare Earth Materials General Research Institute for Non-Ferrous MetalsGrirem Advanced Materials Corporation Limited Beijing 100088 China

Y,Gd)BO_3∶Eu phosphors were prepared by co-precipitation precursors, and luminescent properties were investigated. The precursors were synthesized by introducing hydroxyl ion to mixed solution of rare earth nitrates and boric acid, either through adding ammonia(precursor 1)or through controlled release of hydroxyl ion of urea(precursor 2). The precursors were fired in air at 1000 ℃ for 2 h. Resulted phosphor synthesized with precursor 1 has non-uniformed particle with mean diameter of about 3 μm, while that with precursor 2 exhibits uniformed near spherical-like morphology with mean diameter of about 300 nm. Phosphors with the two methods exhibit same crystal structure as that of commercial one. Emission spectra of the samples indicate that the sample prepared with precursor 2 shows relative higher intensity(exited by 172 nm VUV)than that prepared with the other precursor.

关键词： PDP red phosphor co-precipitation fine particle rare earths