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Microstructures and Mechanical Properties of Al/Mg Alloy Multilayered Composites Produced by Accumulative Roll Bonding

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Journal of Materials science & Technology 2011年第1期27卷 15-21页

作者： h.s. Liu B. Zhang G.P. Zhang shenyang National Laboratory for Materials science Institute of Metal Research Chinese Academy of Sciences Shenyang 110016 China Key Laboratory for Anisotropy and Texture of Materials of Ministry of Education School of Materials & Metallurgy Northeastern University Shenyang 110004 China

Al/Mg alloy multilayered composites were produced successfully at the lower temperature（280 C） by accumulative roll bonding（ARB） processing *** microstructures of Al and Mg alloy layers were characterized by scanning electron microscopy and transmission electron *** hardness and three-point bending tests were conducted to investigate mechanical properties of the *** is found that Vickers hardness,bending strength and stiffness modulus of the Al/Mg alloy multilayered composite increase with increasing the ARB *** and crack propagation along the interface are the two main failure modes of the multilayered composite subjected to bending *** and fracture mechanisms of the composite are analyzed.

关键词： Accumulative roll bonding(ARB) Al/Mg alloy multilayered composite Ultra-fine grains hardness Bending properties

Effect of Reactivity of Quick Lime on the Properties of hydrated Lime sorbent for sO_2 Removal

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Journal of Materials science & Technology 2009年第3期25卷 329-332页

作者： h.G. shin h. Kim Y.N. Kim h.s. Lee Department of Materials science and Engineering Seoul National University Material Analysis Team Korea Testing Laboratory school of Materials science and Engineering Pusan National University

The hydration of quick lime and the sulfation of hydrated lime were carried out for verification of relationship between the reactivity of quick lime and the properties of hydrated lime as a sorbent. The effect of reactivity of quick lime was investigated with the change of calcination temperature and time. Results obtained showed that the temperature rise during the hydration of quick limes varied from 31 to 69℃ with the variation of calcination temperature and time. The specific surface area and the sulfation ability of hydrated lime prepared by hydration of quick lime showed a proportional relationship with the reactivity of quick lime. The hydrated lime which was prepared by hydration of quick lime calcined at 1100℃ had the high.s. reactivity and showed 41.53 m^2/g of the specific surface area, 0.16 cm^3/g of the pore volume and 87% of the removal efficiency for sO2 removal,

关键词： Reactivity Quick lime hydrated lime Calcination hydration sorbent

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAEI h.GhANDVAR E.JUMAEV s.KhATIR T.CUONG-LE school of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and science Center for Engineering Application and Technology solutions Ho Chi Minh City Open University

Th.s.paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with th.s. of the existing literature and commercial software ANsYs, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Variation among poplar clones for growth and crown traits under field conditions at two sites of North-western India

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Journal of Forestry Research 2013年第1期24卷 61-67页

作者： G.P.s. Dhillon Avtar singh D.s. sidhu h.s. Brar Department of Forestry & Natural Resources Punjab Agricultural UniversityLudhiana 141 004India. Punjab Agriculture University Regional Research StationBathinda151 001 PunjabIndia.

We evaluated the growth and crown traits of 36 poplar clones at two distinct agro-climatic regions of Punjab （Ludhiana and Bathinda） in northwestern India, following randomized block design with three replications and plot size of four trees. significant differences among clones （p〈0.001） were observed for diameter at breast height （DBh）, tree height, volume, crown width and number of branch.s.under both the site conditions. Clones ‘G-3’, ‘25-N’ and ‘41-N’ at Ludhiana and ‘G-3’, ‘RD-01’ and ‘s7C8’ at Bathinda were found to be superior for volume production. All growth and crown traits registered significantly higher values at Ludhiana in comparison to th.s. at Bathinda. Clone site interaction was also significant （p〈0.001）. For volume, clones ‘L-62/84’, ‘113520’, ‘25-N’ and ‘s4C2’ witnessed huge fluctuations in ranking between sites. The correlations between growth traits were positive and highly significant （p〈0.001） at both.s.tes. The clonal mean heritability was moderate for DBh and volume both at Ludhiana （0.61–0.66） and Bathinda （0.61–0.62）. Across sites, the genetic advance was the high.s. for volume （49.76%） and the lowest （6.50%） in case of height.

关键词： clonal heritability clonal selection clone-site interaction genetic correlation Populus deltoides

sTRENGThENING CAsT IRON MATRIX BY ALLOYINGELEMENTs WITh POsITIVE AND NEGATIVEsEGREGATION

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Acta Metallurgica sinica(English Letters) 1997年第4期10卷 329-332页

作者： Fan, Z.K. Wang, Y.Q. Liang, s.h. huang, h.s. Xi'an Univ of Technology Xi'an China

The combinational use of alloying elements with positive and negative segregation h.s.been shown to be very effective in strengthening the matrix of cast iron. Negative segregation alloying elements, Cu and si, make the inner parts of dendritic austenites and eutectic cells get good hardenability. On the contrary, positive segregation alloying elements Cr and Mn make the outer parts of dendrites have higher microhardness. Appropriate combination of the above two types of alloying elements can produce a uniform microhardness and high.s.rength in gray cast irons.

关键词： Cast iron Chromium Copper hardness Manganese segregation (metallography) silicon strengthening (metal)

size and shape effects on Curie temperature of ferromagnetic nanoparticles

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中国有色金属学会会刊：英文版 2007年第6期17卷 1451-1455页

作者：曹玲飞谢丹郭明星 h.s. Park T. Fujita school of Engineering University of Tokyo Bunkyo-ku Tokyo 113-8656 Japan Laboratory of Crystallography Department of MaterialsETH-ZürichCH-8093 Zürich Switzerland school of Materials science and Engineering Central South University

A simplified model was developed to describe the Curie temperature suppression of ferromagnetic nanoparticles. Based on a size and shape dependent model of coh.s.ve energy, the critical temperature variations of ferromagnetic nanoparticles were deduced. It is predicted that the Curie temperature of nanoparticles depends on both.s.ze and shape conditions, among which the temperature suppression is strongly influenced by the particle size and the shape effect is comparably minor. The calculation values for freestanding nanoparticles are in good agreement with other theoretical model and the experimental results. The model is also potential for predictions for the nanoparticles embedded in different substrates.

关键词：纳米粒子铁磁体居里温度尺寸形状效应

LAsER CLADDED TiCN COATINGs ON ThE sURFACE OF TITANIUM

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Acta Metallurgica sinica(English Letters) 2007年第3期20卷 210-216页

作者： Y.L. Yang D. Zhang h.s. Kou C. s. Liu College of science Northeastern University Shenyang 110004 China College of Material and Metallurgy Northeastern University Shenyang 110004 China

Laser cladded coatings of TiCN were produced on the surface of titanium. To obtain the optimal techniques, several conditions were tested by varying the laser scanning rate. The choice of shielding gas was also studied. The cladded coatings were then evaluated from the surface mechanics point of view based on their microhardness. The microstructure of some interesting samples was investigated by optical micrographs （OM）. The results showed that under the condition of fixed pulse frequency and pulse width, the laser scanning rate and the shielding gas are the main factors influencing the components of coatings. TiCN coatings were decompounded and oxidized during the cladding process in the condition of no shielding gas of N2. X-ray diffraction results indicated that the composite coatings composed of TiCN, TiC, Ti2N, and TiO2 were produced using appropriate techniques. The results indicated that the best condition in terms of the surface microhardness is obtained when the scanning rate is 1.5mm/s, the pulse frequency is 15hz, the pulse width is 3.0ms, and N2 is ch.s.n as the shielding gas. The microhardness of the composite coatings is about 1331kg · mm^-2, which is about 4 times that of the substrate. The optical micrographs indicated that the cladding zone is made up of TiCN, TiO2 and some interdendritic Ti, but the diffusion zone mainly consists of the dendrites ph.s., and the cladded depth is about 80μm, which is more than 2 times that of the laser nitrided sample. There were no microcracks or air bubbles in the cladded sample, which was cladded using the above optimal techniques.

关键词： laser cladding TiCN coating titanium

Influence of Carrier Gas on Analysis of MgO Powders by Laser Ablation Inductively Coupled Plasma Mass spectrometry

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Journal of Materials science & Technology 2009年第3期25卷 333-335页

作者： J.s. Lee Y.s. Lee C.J. Park h.s. Lee D.s. Lee Department of Chemistry Yonsei University Material Analysis Team Korea Testing Laboratory Korea Research Institute of standards and science school of Material science and Engineering Pusan National Univirsity

Laser ablation inductively coupled plasma mass spectrometry （LA-ICP-Ms） h.s.been widely adopted for the direct multi-elemental analysis with high.s.nsitivity. Especially analysis of fine ceramics by LA-ICP-Ms without time-consuming sample decomposition process h.s.been one of the most expecting application field. small additive elements in MgO powders were analyzed by LA-ICP-Ms. For precise and accurate analysis influence of carrier gas （Ar or he） was presented by the signal intensities of ICP-Ms, relative standard deviation of signal intensities and ablated particle size distribution. Ablated particles were collected and analyzed by scanning electron microscopy （sEM） to investigate the particle size distribution, and the ablated sample surface was examined by camscope. In he gas atmosphere, the signal was more stable than in Ar gas atmosphere. The signal intensity was higher in Ar than in he. Examination of ablated particles and sample surface reveals that more particles were generated in Ar atmosphere and the distribution of particle size was larger.

关键词： Laser ablation MgO powders Carrier gas ICP-Ms

EFFECT OF COPPER ON ThE hOT PLAsTICITY OF 304hC sTAINLEss sTEEL

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Acta Metallurgica sinica(English Letters) 2005年第5期18卷 674-678页

作者： G.Z. Cui h.s. Di G.D. Wang X. h. Liu state Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

The plasticity map of 304hC stainless steel was determined by using tensile and compressive test. The effect of Cu on the hot plasticity of 304hC stainless steel was analyzed. The microstructure, inclusion and fracture surface were studied by using the method of optical microscopy, sEM, EDs and EPMA. The results showed that Cu h.s.effect on the hot plasticity and the hot plasticity of 304hC stainless steel decrease with the increase of Cu content. The deformation temperature also h.s.much effect on the hot plasticity, the suitable deformation temperature are 1100-1200℃. The reason is that the brittle compounds were precipitated from austenite during cooling. Th.s. brittle compounds are Cu2s, Cu2O and PbCI etc.

关键词： 304hC stainless steel hot plasticity brittle compounds precipitation,impurity crack microstructure