材料期刊网

Hardness, Wear Resistance and nacture Toughness of Cast Hiduminium/Corundum Particulate Composites

K.H.W.Seah(Dept. of Mechanical Engineering , National University of Singapore , 10 Kent Ridge Crescent , Singapore 119260)R.S.Kulkarni and S.C.Sharma (Dept. of Mechanical Engineering , R.V.College of Engineering , Mysore Road , Bangalore-560-059 , Karnataka , Ind

材料科学技术（英文）

This paper reports some results obtained in an investigation to see how increasing the corundum dispersoid content from 0% to 7% in a matrix of as-cast and wrought hiduminium alloy affects the hardness. wear resistance and fracture toughness of the composite. The results show that as the corundum content is increased, the hardness and the wear resistance increase remarkably,whereas the fracture toughness drops significantly. It was found that Just a minute amount of corundum is sufficient to cause a fairly large change in these mechanical properties. The hardness of the material is also affected signifIcantly by the aging time. Moreover, if other factors are kept constant, hot extrusion improves both its hardness and its wear resistance. whereas the fracture toughness is decreased

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Properties of Cast Hiduminium/Corundum Particulate Composites

K.H. W. Seah(Dept. of Mechanical Engineering , National University of Singapore , 10 Kent Ridge Crescent , Singapore 0511)R.S.Kulkari and S.C.Sharma (Dept. of Mechanical Engineering , R.V.College of Engineering , Mysore Road , Bangalore-560-059 , Karnataka , Indi

材料科学技术（英文）

This paper reports some results obtained in an investigation to see how increasing the corundum dispersoid content from o% to 7% in a matrix of hiduminium alloy affects the tensile and compressive strengths, the hardness and the casting characteristics of the composite. The results show that as the corundum content is increased, ultimate tensile strength (UTS)- compressive strength and hardness increase remarkably, whereas fluidity of the molten composite during casting drops significantly. It was found that just a minute amount of corundum is sufficient to cause a fairly large change in the mechanical properties and the fluidity of the molten material.This drop in castability is one of the reasons why adding corundum beyond 7 percent is not recommended. If other factors are kept constant, the fluidity is seen to slightly improve if the pouring temperature of the molten metal were increased from 670 to 710℃

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Influence of Coolant on Cutting Tool Performance

K.H.W.Seah and X.Li(Dept. of Mechanical and Production Engineering , National University of Singapore , 10 Kent Ridge Crescent , Singapore 119260)

材料科学技术（英文）

This paper reports a Study carried out to substantiate or refute the belief that when coolant is applied, the cutting performance is actually improved. Experiments on cutting forces and chip geometry were conducted in which AISI 1050 Steel was machined by turning using P30 uncoated tungsten carbide tools. Experiments were performed on a CNC Okuma LH35-N lathe undermachining conditions commonly used in workshops in Singapore and many other parts of the world.

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Compressive fracture of Zr55Al10Ni5Cu30 bulk amorphous alloy at high temperatures

Materials Science and Engineering a-Structural Materials Properties Microstructure and Processing

The fracture behavior of the Zr55Al10Ni5Cu30 bulk amorphous alloy under uniaxial compression at high temperatures has been investigated. At room temperature, the fracture occurred along the maximum shear plane which declined by 45degrees to the direction of the applied load, and a crack with serrated edge appeared on the ridge of the veins at the fracture surface for the Zr55Al10Ni5Cu30 bulk amorphous alloy. At high temperatures, the compressive fracture surface of the Zr55Al10Ni5Cu30 bulk amorphous alloy became much rougher than that at room temperature and steps appeared on the fracture surface. With increasing temperature, a different pattern from the vein-like morphology appeared on the fracture surface, which is very similar to the lava-flow. This type of fracture pattern is most likely due to the adiabatic heating created by plastic flow. (C) 2003 Elsevier B.V. All rights reserved.

关键词: bulk amorphous alloy;fracture;shear band;plastic deformation;adiabatic heating;supercooled liquid region;fatigue-crack-propagation;metallic-glass;mechanical-properties;ni;deformation;flow

The Simultaneous Determination of Five Components Including Acetaminophen by Ridge Regression Spectrophotometry

武汉理工大学学报-材料科学版(英文版)

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ZG10MnNiCu钢的试制

黄飞 , 朱伟伟 , 杨海石 , 刘军

钢铁研究

ZG10MnNiCu钢用于制造高强度厚壁铸件,其对C,H,O等元素的含量要求严格.上海电气上重铸锻有限公司根据此钢种的成分要求,制定了冶炼试制的生产工艺,通过严格控制配料、脱磷、脱碳、精炼等工艺,试制成功了ZG10MnNiCu钢.成品钢中w(C)<0.10 %、w(H)<1.5×10-6、w(O)<20×10-6、w(N)<70×10-6,满足了对此钢种的内控成分要求.

关键词: ZG10MnNiCu钢 , 含铜厚壁铸件 , 脱磷 , 脱碳

Effect of Co Ion Implantation on GMR of [NiFeCo(10 nm)/Ag(10 nm)]×20 Multilayer Film

Yuding HE , Shejun HU , Jian LI , Guangrong XIE

材料科学技术（英文）

The composition, phase structure and microstructure of the discontinuous multilayer film [NiFeCo(10 nm)/ Ag(10 nm)]×20 were investigated after Co ion implantation and annealing at 280, 320, 360 and 400℃, respectively. GMR (giant magnetoresistance) ratio of the film with/without Co ion implantation was measured. The results showed that Co ion implantation decreased the granule size of the annealed multilayer film, and increased Hc value and GMR ratio of the multilayer film. After annealing at 360℃, the multilayer film [NiFeCo(10 nm)/Ag(10 nm)]×20 with/without Co ion implantation both exhibited the highest GMR ratio of 12.4%/11% under 79.6 kA/m of applied saturation magnetic field.

关键词: Co ion implantation , null , null

AlN(10-10)表面结构的第一性原理计算

贾伟 , 王进 , 韩培德 , 党随虎 , 迟美 , 刘旭光 , 许并社

材料导报

采用基于密度泛函理论的第一性原理方法,计算了六方AlN及其(10-10)表面的原子及电子结构.其中计算出的六方AlN晶体中的晶格常数和体弹性模量与实验值很符合.用平板超原胞模型模拟计算AlN(10-10)表面的原子及电子结构,结果表明:AlN(10-10)表面弛豫后,表面顶层原子之间的键长收缩并发生扭转.表面原子均向体内移动,原子轨道重新杂化,N原子趋向于p3构型,Al原子趋向于sp2构型.

关键词: AlN , 密度泛函理论 , 表面态 , 能带结构 , 态密度

80%Fe-10%Co-10%Ni合金粉的制备

田伟杰 , 丁军红 , 李在元

硬质合金 doi:10.3969/j.issn.1003-7292.2009.03.005

采用共沉淀方法制备了80%Fe-10%Co-10%Ni前驱体粉,考察了搅拌强度、滴定终点溶液的pH值、反应温度和反应时间对前驱体粉回收率的影响,并通过三因素三水平的正交实验,优化了工艺条件.采用氢还原法制备了80%Fe-10%Co-10%Ni合金粉,考察了还原温度对转化率和平均粒度的影响.实验结果表明:制备前驱体粉的工艺条件为搅拌强度2 000 r/min、pH值为11、反应温度20℃、反应时间35 min;氢还原法制备80%Fe-10%Co-10%Ni合金粉的工艺条件为:反应温度700℃、反应时间30min;还原温度越高,反应速度越快,产品粒度越大.

关键词: Fe/Co/Ni , 合金粉 , 枯接剂 , 氢还原

第10届国际真空冶金大会

金属学报

<正> 1990年国际特种熔炼会议 1990年国际冶金涂层会议 经国家科委批准,第10届国际真空冶金大会将于1990年6月11—15日在北京举行。 一、会议宗旨 特种熔炼冶金和金属表面处理技术是当前国际上最活跃的研究领域之一,并有重要的应用价值。本次会议宗旨在于进行学术交流和讨论,促进国际科技合作和科学技术进步。 二、会议内容 大会含特种熔炼和冶金涂层两个会议,学术交流内容如下:

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