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High pressure x-ray diffraction study of SrMnO_3 perovskite

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Chinese Physics C 2011年第5期35卷 514-518页

作者：刘迎新秦善巫翔蒋建中 Kikegawa Takumi 施光海 State Key Laboratory of Geological Processes and Mineral Resources China University of Geosciences Department of Geology and Key Laboratory of Orogenic Belts and Crustal Evolution of MOE Peking University International Center for New-structured Materials (ICNSM) Zhejiang University Laboratory of New-structured Materials Department of Materials Science and Engineering Zhejiang University Institute of Materials Structure Science High Energy Accelerator Research Organization

Using a diamond anvil cell device and synchrotron radiation, the in-situ high-pressure structure of SrMnO 3 has been investigated. At pressure up to 28.6 GPa, no pressure-induced phase transition is observed. The lattice parameters as a function of pressure is reported, and the relationship of the axial compression coefficients is β a 〉 β c . The isothermal bulk modulus K 298 =266（4） GPa is also obtained by fitting the pressure- volume data using the Murnaghan equation of state.

关键词： SrMnO3 high-pressure structure phase transition x-ray diffraction

Magnetostrictive distortion in Pr_(0.15)Tb_xDy_(0.85-x)Fe_2 polycrystals by x-ray diffraction

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Journal of Central South University of Technology 2005年第1期12卷 39-41页

作者：孟凡斌李养贤陈贵锋刘何燕曲静萍陈京兰吴光恒 School of Materials Science and Engineering Hebei University of TechnologyTianjin 300130 China State Key Laboratory for Magnetism Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The ingots of Pr0.15TbxDy0.85-xFe2 （x=0.10-0.85） series compounds with a single phase were prepared -by a arc melting method. The x-ray diffraction patterns were measured using a Philips x’pert MPD x-ray diffractometer with a non-ambient sample stage at different temperatures, the magnetostrictive distortion in (Pr0.15TbxDy0.85-xFe2) polycrystals was investigated by x-ray diffraction patterns and the magnetostriction coefficient λ111 was calculated. The results show -when the temperature is raised above the spin reorientation temperature region, a splitting appears in the reflection （440）; the λ111 increase with the increasing of Tb content for (Pr0.15TbxDy0.85-xFe2) polycrystals and the full width at half maximum （FWHM） of the reflection （440） increases gradually with the increasing of Tb content. Moreover, as the FWHM of the reflection （440） decreases gradually with the increasing of temperature, the λ111 decreases slightly with the increasing of temperature at the temperature region of 223-373K for Pr0.15Tb0.3Dy0.55Fe2 alloy.

关键词： magnetostriction distortion x-ray diffraction

x-ray diffraction performance of thermally distorted crystals

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High Power Laser Science and Engineering 2023年第6期11卷 29-38页

作者： Chuan Yang Tao Liu Kai Hu Ye Zhu xiaohao Dong Zhongmin xu Chao Feng Weiqing Zhang Institute of Advanced Science Facilities ShenzhenChina College of Science Southern University of Science and TechnologyShenzhenChina Shanghai Advanced Research Institute Chinese Academy of SciencesShenzhenChina State Key Laboratory of Molecular Reaction Dynamics Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalianChina

The development of high-brightness x-ray free electron lasers(xFELs),such as hard x-ray self-seeding free electron lasers and xFEL oscillators(xFELOs),brings a severe challenge to the crystal monochromator due to a strong nonuniform thermal *** distortion caused by spatial temperature gradients can severely affect the optical performance of ***,this paper presents a model to estimate the performance of non-uniform thermally distorted *** model not only takes into account thermal strain,slope error and incident angle deviation,but also considers temperature-dependent factors such as the Debye-Waller factor and electric *** investigation indicates that the Debye-Waller factor reduces the height and bandwidth of rocking curves,and the impact of the electric susceptibility is *** proposed model can describe the distortion of the reflectivity and transmissivity curves of nonuniform thermally loaded crystals and can be applied in the design of crystal monochromators,crystal splitters,crystal compressors and xFELOs.

关键词： crystal monochromator free electron laser thermal load x-ray diffraction

x-ray diffraction Study of a Quasicrystalline Alloy Stable at High Temperature

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Rare Metals 1993年第2期12卷 148-151页

作者：钱崇梁蒋向阳陈振华 Powder Metallurgy Research Institute Central-south University of Technology Changsha 410083 China

Crystalline A1-Cu-Fe-Mg alloy powders were produced by means of rapid *** annealing process,the quasicrystalline icosahedral phase formed at about 625°C and was stable until 900°*** quasicrystalline phase is conside... 详细信息

关键词： Quasicrystalline alloy Rapid solidification x-ray diffraction

x-ray diffraction study of effect of deposition conditions on α-β phase transition and stress evolution in sputter-deposited W coatings

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Chinese Physics B 2006年第2期15卷 432-436页

作者：王聪 Brault Pascal Pineau Alain Plantin Pascale Thomann Anne-Lise Groupie de Recherches sur I'Energétique des Milieux Ionisés UMR6606 -CNRS Ecole Polytechnique de I'Université d'Orléans BP6744 Université d'Orléans F-45067 Orléans Cedex 2 France School of Science Beijing University of Astronautics and Aeronautics Beijing 100083 China Centre de Recherches sur la Matière Divisée - UMR 6619 CNRS - Université d'Orléans 1B rue de la Férollerie 45071 Orldans Cedex 2 France

Pure W and W-Cu-W trilayer coatings were deposited on an Fe substrate by d.c. magnetron sputtering. The α-β phase evolution, intragranular stress evolution in sputter-deposited W layer were investigated by x-ray diffraction. They are directly related to the film microstructure, density and adhesion. Therefore, control of the film stress and phase component transition is essential for its applications. The phase component transition from β-W to α-W and intragranular stress evolution from tensile to compressive strongly depend on the deposition parameters and can be induced by lowering Ar pressure and rising target power. The compressively stressed films with α-W phase have a dense microstructure and high adhesion to Fe substrate.

关键词： W coatings x-ray diffraction α-β phase component transition thin film stress

Rietveld refinement of powder x-ray diffraction,microstructural and mechanical studies of magnesium matrix composites processed by high energy ball milling

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Journal of Magnesium and Alloys 2018年第4期6卷 390-398页

作者： T.Ramkumar M.Selvakumar R.Vasanthsankar A.S.Sathishkumar P.Narayanasamy G.Girija Department of Mechanical Engineering Dr.Mahalingam College of Engineering and TechnologyPollachi 642003India Department of Automobile Engineering Dr.Mahalingam College of Engineering and TechnologyPollachi 642003India Department of Mechanical Engineering Sree Sowdambika College of EngineeringAruppukottai 626134India Department of Mechanical Engineering Kamaraj College of Engineering and TechnologyVirudhunagar 626001India

This research reports the processing of magnesium matrix composites reinforced with silicon carbide(SiC)and aluminium oxide(Al_(2)O_(3))using powder metallurgy technique through high energy *** of Mg-SiC and Mg-Al_(2)O_(3)composites subjected to high energy ball milling for different vol%of secondary particles 20,30 and 40%of SiC and Al_(2)O_(3)are studied by x-ray diffraction *** rietveld method as implemented in the Fullprof program is applied in order to determine the quantities of the resulting crystalline phases and amorphous phases at each stage of the mechanical *** examination is carried out using Scanning Electron Microscope(SEM).In addition,crystal structural analysis using appropriate size and strain models is performed in order to handle the distinctive anistrophy that is observed in convinced crystallographic directions for the magnesium *** results are furnished in terms of crystalline domains size enlargement of the magnesium composites phases upon prolonged milling duration and discussed in the light of up to date views and theories on crystal growth of nanocrystaline *** hardness of the composite samples is calculated by Vickers’s Hardness ***,dry sling wear test and corrosion test are performed for the fabricated *** with 30%secondary particles incorporated magnesium composites exhibits better wear and corrosion resistance than the other composites.

关键词： Rietveld refinement x-ray diffraction Crystal structure Micro structure Wear and corrosion

Microfibril angle variability in Masson Pine (Pinus massoniana Lamb.) using x-ray diffraction

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Forestry Studies in China 2007年第1期9卷 33-38页

作者： Zhang Bo Fei Ben-hua Yu Yan Zhao Rong-jun Research Institute of Wood Industry Chinese Academy of Forestry Beijing 100091 E R. China International Center for Bamboo and Rattan Beijing 100102 P. R. China

The microfibril angle of fiber walls is an ultra-mieroscopic feature affecting the performance of wood products. It is therefore essential to get more definitive information to improve selection and utilization. x-ray diffraction is a rapid method for measuring microfibril angles. In this paper, the variability of microfibril angle in plantation-grown Masson pine was investigated by peak-fitting method. This method was compared with the traditional hand-drawn method, 40% peak height method and half peak height method. x-ray diffraction measurements indicated that the microfibril angle changed as a function of the position in the tree. The mean microfibril angle decreased more gradually as the distance increased from the pith and reached the same level in mature wood. The microfibril angle also seemed to decrease clearly from the base upward. Differences of angle-intensity curves between heartwood and sapwood were also examined.

关键词： x-ray diffraction microfibril angle peak-fitting method half peak height method Masson pine

Residual stress measurement of coarse-grain aluminum alloy using x-ray diffraction method

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China Welding 2016年第2期25卷 34-39页

作者： Sun Jiantong Li xiaoyan Zhang Liang Yan Wentao Li Qingqing Beijing University of Technology Beijing 100124

When measuring residual stress of coarse-grain aluminum alloy using x-ray diffraction method, the diffraction profile shows two peaks and position of measured 20 will be changed, which lead to an inaccurate measurement result. Hence, in this paper, some methods were employed to improve the measurement accuracy. During the measuring process, different parameters （diameter of irradiated area, Ψ-oscillation range and exposure time） were selected and profile peak shift method was utilized. Moreover, when the 20 of profiles was determined, different calculation methods were used to calculate the residual stress. The results show that diameter of irradiated area and Ψ-oscillation range have significant influence on the measuring result. For stress value calculated directly from the test equipment, cross correlation method is more accurate than the absolute peak. Furthermore, another two calculation methods of slope with 2θ- sin^2Ψ and ε- sin^2Ψwere used to calculate the stress based on parameters （2θ, ε） obtained from cross correlation method. It is concluded that 2θ - sin^2Ψ method can further improve the measurement accuracy.

关键词： coarse grain residual stress x-ray diffraction

Interactions between Copper Atoms and Rubber Molecules by x-ray diffraction

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工程科学学报 1991年第2期 150-153页

作者：刘金麟穆承章卢于逑北京科技大学压力加工系

In order to determine the interactions between copper atoms and rubber molecules, this article used x-ray diffraction to analyse the cure specimen of size materials mixed with copper powder for the first time, found the atomic nucleus distances between copper and atoms in rubber molecules were equal to 0.23169nm and 0.3043nm. 0.3043nm reflected the atomic distance between Cu and S under the action of Van der Waals force. 0.23169nm stated that there was chemical interaction between Cu atoms and rubber molecules.

关键词： rubber copper interaction x-ray diffraction