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3D Morphology and Formation Process of the Icosahedral Quasicrystalline Phase in Rapidly Solidified Al-Mn Alloy

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Acta Metallurgica Sinica(English Letters) 2016年第1期29卷 28-31页

作者： Hui-Jun Kang Zhong-Lue Hu Xiao-Xia Gao Zong-Ning Chen Yi-Ping Lu jin-chuan jie jing-jie Guo Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of Technology Department of Mechanical Engineering Texas Tech University School of Materials Science and Engineering Harbin Institute of Technology

Three-dimensional morphology and formation process of icosahedral quasicrystal phase have been investigated in a melt-spun AI-18Mn alloy （in wt%）. Three distinct layers corresponding to varying temperature gradient have been observed on the cross section of the ribbons. 3D morphologies of cellular and dendritic icosahedral phase have been obtained through electro-etching. A model has been proposed to describe the formation process of the icosahedral phase and a-A1 during the rapid solidification. The icosahedral phases are primarily precipitated from the melt into fine cellular and dendritic particles, and subsequently engulfed by the a-A1 which propagates in a planar morphology.

关键词： Rapid solidification Microstructure Icosahedral quasicrystal Aluminum-manganese alloy

Interfacial phase formation of Al-Cu bimetal by solid-liquid casting method

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China Foundry 2017年第3期14卷 194-198页

作者： Ying Fu Yu-bo Zhang jin-chuan jie Kateryna Svynarenko Chang-hai Liang Ting-ju Li School of Materials Science and Engineering Dalian University of Technology Dalian 116024 Liaoning China Research Institute of Mechatronics & Automation Bohai University Jinzhou 121003 Liaoning China School of Chemical Engineering Dalian University of Technology Dalian 116024 Liaoning China

The solid-liquid method was used to prepare the continuous casting of copper cladding aluminium by liquid aluminum alloy and solid copper, and the interfacial phase formation of Al-Cu bimetal at different pouring temperatures(700, 750, 800 oC) was investigated by means of metallograph, scanning electron microscopy(SEM) and energy dispersive spectrometry(EDS) methods. The results showed that the pouring temperature of aluminum melt had an important influence on the element diffusion of Cu from the solid Cu to Al alloy melt and the reactions between Al and Cu, as well as the morphology of the Al-Cu interface. When the pouring temperature was 800 oC, there were abundant Al-Cu intermetallic compounds(IMCs) near the interface. However, a lower pouring temperature(700 oC) resulted in the formation of cavities which was detrimental to the bonding and mechanical properties. Under the conditions in this study, the good metallurgical bonding of Al-Cu was achieved at a pouring temperature of 750 oC.

关键词： Al-Cu clad materials interface solid-liquid method microstructure

Boron removal from molten silicon using CaO-SiO_2-BaO-CaF_2 slag

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Transactions of Nonferrous Metals Society of China 2016年第12期26卷 3299-3304页

作者： jin-ling SUN jin-chuan jie Qing-chuan ZOU Li-juan GUO Zhi-qiang CAO Tong-min WANG Ting-ju LI School of Materials Science and Engineering Dalian University of Technology Dalian 116024 China TDK Dalian Corporation Dalian 116024 China

The distribution coefficient (LB) of boron between CaO?SiO2?BaO?CaF2 slag and silicon was investigated usingelectromagnetic induction melting for the purpose of improving the boron removal fraction. The dependence of the borondistribution coefficient between slag and silicon on the fundamental parameters of CaO to SiO2 mass ratio and refining time and theadditions of BaO and CaF2 to the slag was discussed. The results show that LB can be increased by adding BaO and CaF2 toCaO?SiO2 slag. The maximum value of LB (6.94) is obtained when the CaO to SiO2 mass ratio is 1.1:1 and the contents of BaO andCaF2 are fixed at 15% and 20%, respectively. Increasing the refining time increases the LB. After the slag treatment is performedtwice, the boron content of the silicon is successfully reduced from 3.5×10?5 to 3.7×10?6, and the removal fraction of boron reaches89.4%.

关键词： metallurgical silicon boron removal CaO-SiO2-BaO-CaF2

Grain refinement of pure aluminum by direct current pulsed magnetic field and inoculation

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Transactions of Nonferrous Metals Society of China 2014年第5期24卷 1295-1300页

作者：陈航接金川付莹马红军李廷举大连理工大学材料科学与工程学院大连116023

The combined effects of direct current pulsed magnetic field （DC-PMF） and inoculation on pure aluminum were investigated, the grain refinement behavior of DC-PMF and inoculation was discussed. The experimental results indicate that the solidification micro structure of pure aluminum can be greatly refined under DC-PMF. Refinement of pure aluminum is attributed to electromagnetic undercooling and forced convection caused by DC-PMF. With single DC-PMF, the grain size in the equiaxed zone is uneven. However, under DC-PMF, by adding 0.05% （mass fraction） Al5Ti-B, the grain size of the sample is smaller, and the size distribution is more uniform than that of single DC-PMF. Furthermore, under the combination of DC-PMF and inoculation, with the increase of output current, the grain size is further reduced. When the output current increases to 100 A, the average grain size can decrease to 113 μn.

关键词： direct current pulsed magnetic field pure aluminum inoculation grain refinement solidification micro structure

Effect of immersion Ni plating on interface microstructure and mechanical properties of Al/Cu bimetal

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Transactions of Nonferrous Metals Society of China 2014年第6期24卷 1659-1665页

作者：赵佳蕾接金川陈飞陈航李廷举曹志强大连理工大学材料科学与工程学院大连116024

A nickel-based coating was deposited on the pure Al substrate by immersion plating,and the Al/Cu bimetals were prepared by diffusion bonding in the temperature range of 450-550 ℃.The interce microstructure and fracture surface of Al/Cu joints were studied by scanning electron microscopy（SEM） and X-ray diffraction（XRD）.The mechanical properties of the Al/Cu bimetals were measured by tensile shear and microhardness *** results show that the Ni interiayer can effectively eliminate the formation of Al-Cu intermetallic *** Al/Ni interface consists of the Al3Ni and Al3Ni2 phases,while it is Ni-Cu solid solution at the Ni/Cu *** tensile shear strength of the joints is improved by the addition of Ni *** joint with Ni interiayer annealed at 500 ℃ exhibits a maximum value of tensile shear strength of 34.7 MPa.

关键词： Al/Cu bimetal immersion Ni plating interface diffusion bonding intermetallics

Wear behavior of high strength and high conductivity Cu alloys under dry sliding

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Transactions of Nonferrous Metals Society of China 2015年第7期25卷 2293-2300页

作者：高原接金川张鹏超张剑王同敏李廷举大连理工大学材料科学与工程学院大连116024 北京赛尔克瑞特电工有限公司北京100070

In order to study the wear behavior of different kinds of contact wires,the dry sliding wear behaviors of Cu-Sn,Cu-Ag and Cu-Mg alloys prepared by up-drawn continuous casting and followed continuous extrusion were *** research was tested on a block-on-ring wear *** results indicate that the friction coefficient is remarkably influenced by the formation of a continuous tribofilm,which consists of oxidation *** abrasion,adhesion,oxidation and plastic deformation are *** and abrasion wear mechanisms dominate at the lower sliding velocity and *** combination of oxidation and adhesion play leading roles with the increasing load and *** deformation is detected under higher applied load and sliding velocities.

关键词： copper alloys contact wire sliding wear mass loss wear mechanism electron microstructure

Microstructure evolution of 3003/4004 clad ingots under diverse physical fields

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Transactions of Nonferrous Metals Society of China 2013年第9期23卷 2496-2501页

作者：付莹接金川张宇博钟德水李继展李廷举大连理工大学材料科学与工程学院大连116024

In order to improve the quality of clad ingots, diverse physical fields including electromagnetic stirring, power ultrasonic and compound field of ultrasonic and electromagnetic stirring were attempted to prepare clad ingots of 3003/4004 alloys. The solidification structures near the interface in clad ingots were investigated. The experiment results indicate that the solidification structure of 4004 alloy changes from dendritic crystals to petal-like grains when the clad ingot is treated by electromagnetic stirring. With the effect of power ultrasonic, the solidified microstructure of 4004 alloy exhibits the refinement of both primary a（A1） and eutectic silicon. Under the compound field, the primary a（A1） is refined, the morphology of eutectic silicon has a transition from a coarse plate-like form without treatment or thin acicular-like form with power ultrasonic to fine coral-like form.

关键词： A1 alloy clad ingot power ultrasonic electromagnetic stirring compound field structure

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哌拉西林治疗老年性肺炎75例

新药与临床 1989年第5期8卷 267-269页

作者：张进川丁杰李峻亨中国人民解放军总医院北京100853

本文报告哌拉西林治疗75例老年人(54M,21F,年龄65±7yr)肺炎的结果,经过4-16g/d(9.3±2.7g/d)5-32d(8±5d)的治疗,有效率为95%。未见肝、肾功能副作用,说明哌拉西林对老年肺炎的治疗是安全和有效的。

关键词：哌拉西林肺炎老年人

Overflowing phenomenon during ultrasonic treatment in Al-Si alloys

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Transactions of Nonferrous Metals Society of China 2013年第11期23卷 3242-3248页

作者：张宇博卢一平接金川傅莹钟德水李廷举大连理工大学材料科学与工程学院大连116024

At the late stage of solidification with ultrasonic treatment （UST） in Al-Si alloys, a part of semisolid overflows and climbs along the probe. The interesting phenomenon and its influence on the solidification microstructure were investigated in order to better study the mechanism of UST. It is considered that the overflowing phenomenon occurs due to the changes of vibration and flow in the remaining semisolid. Because the overflowed portion comes from the region with intense UST effect and vibrates with the probe during solidification, great modification of primary and euteetic Si （about 10 pm in length） and refinement of primary a（Al）（about 70 μm in size） are observed in this portion.

关键词： Al-Si alloy ultrasonic treatment overflowing phenomenon solidification microstructure