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中国有色金属学会会刊：英文版 2010年第S3期20卷 734-738页

作者： S.TERZI L.SALVO M.SUERY a.dahle E.BOLLER Australian Research Council Centre of Excellence for Design in Light Metals Materials EngineeringThe University of QueenslandBrisbane Queensland 4072Australia Université de Grenoble Science et Ingénierie des Matériaux et ProcédésGénie Physique et Mécanique des MatériauxUMR CNRS 5266Grenoble INPUniversité Joseph FourrierBP4638402 Saint-Martin d'Hères CedexFrance European Synchrotron Radiation Facility 6 rue Jules HorowitzBP22038043 Grenoble CedexFrance

The aim of this paper is to report the results of experiments carried out on Al-Cu alloys with different Cu contents,studying the microstructure evolution during holding in the semi-solid *** 3-D microstructure was observed by in situ X-ray microtomography carried out at ESRF Grenoble,*** variation of the solid-liquid interface area per unit volume during holding was *** addition,local observations show that two coarsening mechanisms of the solid particles occur simultaneously:dissolution of small particles to the benefit of larger ones by an Ostwald-type mechanism and the growth of necks between solid particles due to *** observations confirm that in situ X-ray tomography is a very powerful tool to study the microstructure evolution in the semi-solid state and the influencing mechanisms in real-time.

关键词： Al-Cu alloys microtomography remelting microstructure

Improvement of warm formability of Al-Mg sheet alloys containing coarse second-phase particles

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Science China(Technological Sciences) 2009年第1期52卷 41-45页

作者： Arne K dahle Amit K GHOSH Materials Engineering University of Queensland Department of Materials Science and Engineering University of Michigan

Several alloying elements involving Zr, Cu, Zn and Sc were added to Al-Mg sheet alloys in order to obtain an excellent combination of high strength and good high-temperature formability. Microstruc-tural examination showed that coarse intermetallic particles were formed in the microstructure and their amounts changed with variations of the alloying elements. During warm rolling of thermome-chanical treatments prior to warm deformation, the coarse particles initiated cracks, decreasing the warm formability. For healing the crack damage and further improving the warm formability, a process of hot isothermal press was developed and optimized to the sheet alloys. With this process, the biaxial stretch formability at 350℃ was improved by 22% for an aluminum alloy containing a large amount of coarse particles.

关键词： aluminum alloy microstructure second-phase particle hot isothermal press high-temperature formability

Shear band formation in shaped rheocast aluminium component at various plunger velocities

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Transactions of Nonferrous Metals Society of China 2010年第9期20卷 1749-1755页

作者： M.BLADH M.WESSN A.K.dahle Swerea SWECAST AB Materials and Manufacturing-Casting School of EngineeringJnkping University Materials Engineering The University of Qu eensland

Significant progress has been made in recent years in understanding and modelling the rheology of semi-solid *** models show the effects of the microstructure in terms of size and morphology of globules on the material *** recently it has been shown that semi-solid metals can behave as compacted granular materials such as sand.A particular signature of such deformation is that the deformation becomes concentrated into shear bands which are 10-20 grains *** bands have also been observed in a range of cast ***, it has been clearly shown that shear bands in high pressure die cast (HPDC) products are also the results of Reynolds *** bands are also known to be a common feature in semi-solid metal *** segregation banding in semi-solid metal (SSM) material and its dependence of plunger velocity were *** castings were made with the RHEOMETALTM process with a range of different plunger *** microstructural characteristics were investigated, with a particular emphasis on shear *** is shown that ingate velocities influence the location and characteristics of the shear bands.

关键词： rheocasting shear bands segregation Al-alloys RHEOMETAL^TM

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高地应力岩体特殊照明峒室围岩支护设计

岩石力学与工程学报 2008年第1期27卷 35-41页

作者：吕明 GRφV E dahle H 乔怀玉文邦后陈忠明赵秋林挪威SINTEF集团岩土力学研究所挪威特隆赫姆7465 陕西公路隧道建设管理中心陕西西安710068 铁道第一勘测设计院陕西西安710043

为特殊照明和交通安全在世界最长的双峒公路隧道——秦岭终南山隧道内设计了6个峒室,该隧道穿越中国陕西省秦岭山脉,最大埋深达1 800 m。在峒址附近的2个位置采用应力解除法量测岩石地应力,该处的岩石覆盖厚度分别为1 600和400 m,量测... 详细信息

为特殊照明和交通安全在世界最长的双峒公路隧道——秦岭终南山隧道内设计了6个峒室,该隧道穿越中国陕西省秦岭山脉,最大埋深达1 800 m。在峒址附近的2个位置采用应力解除法量测岩石地应力,该处的岩石覆盖厚度分别为1 600和400 m,量测结果显示极高的地应力。为满足照明和行车安全的要求,每个峒室设计成纺锤型,长度为200 m,最大宽度为22 m。受到已建成隧道的限制,两峒室间最小岩柱厚度只有8 m。峒室的主要特征为:(1)高地应力;(2)岩石条件较好;(3)与峒室尺寸相比岩柱厚度很小,这些特征对围岩支护提出极大的挑战。围岩支护是依据岩体分类Q系统采用经验法设计,然后采用数值分析校核。临时支护和永久支护系统均采用喷射混凝土和锚杆。为保证施工和运行期的峒室稳定提出一整套实施程序,包括开挖、喷射混凝土、安装锚杆和监控措施。对于极高地应力区域的峒室采用柔性支护,允许岩体在永久支护安装前发生部分变形,从而保证峒室稳定及支护元件安全可靠地发挥效用。分别采用FLAC3D和Phase 2程序进行三维和二维数值分析,三维计算主要用于研究峒室的整体稳定及沿隧道轴向的三维效应;二维计算用于详细研究施工顺序和各支护单元的功效。数值分析显示喷射混凝土和锚杆在各施工阶段都能安全运作,从而验证了围岩支护设计。

关键词：隧道工程公路隧道围岩支护设计地应力数值分析岩体分类

Improvement of warm formability of Al-Mg sheet alloys containing coarse second-phase particles

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中国科学:技术科学 2010年第4期40卷 434-434页

作者： Arne K dahle Amit K GHOSH Materials Engineering University of Queensland Department of Materials Science and Engineering University of Michigan

Several alloying elements involving Zr,Cu,Zn and Sc were added to Al-Mg sheet alloys in order to obtain an excellent combination of high strength and good high-temperature *** examination showed that coarse intermetallic particles were formed in the microstructure and their amounts changed with variations of the alloying elements. During warm rolling of thermomechanical treatments prior to warm deformation,the coarse particles initiated cracks,decreasing the warm *** healing the crack damage and further improving the warm formability,a process of hot isothermal press was developed and optimized to the sheet *** this process,the biaxial stretch formability at 350°C was improved by 22%for an aluminum alloy containing a large amount of coarse particles.

关键词： aluminum alloy microstructure second-phase particle hot isothermal press high-temperature formability

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挪威的地震危险性

防灾减灾工程学报 1995年第S1期 31-32页

作者： Anders dahle

1 地震危险性评定历史挪威最早的地震危险性研究起始于1970年代中期,当时政府机构为Statkraft水电站和挪威南部的核电站场地进行可行性研究。80年代初,挪威当局在挪威大陆架安全(SPS)这项研究计划中回顾了日益增长的挪威近海工业的安全... 详细信息

1 地震危险性评定历史挪威最早的地震危险性研究起始于1970年代中期,当时政府机构为Statkraft水电站和挪威南部的核电站场地进行可行性研究。80年代初,挪威当局在挪威大陆架安全(SPS)这项研究计划中回顾了日益增长的挪威近海工业的安全要求,也考虑到地震危险性(Ringdal等,1982)。1987年,正式制定了有关固定的近海设施地震危险性评定规范(NPD,1987)。根据综合研究计划“挪威大陆架地震荷载”(ELOCS)(Bungum和Selnes,1988),目前正着手准备对现今规范进行修订。

关键词：地震危险性 NPD 地面运动概率地壳运动区域台网北欧挪威