Cu-Zr基金属玻璃的形成能力及力学性能研究

用铜模吸注方法制备了不同直径的Cu47.5Zr47.5Nb5金属玻璃,并用X-Ray对制备的金属玻璃进行了结构测定,同时对金属玻璃进行了压缩实验及断口分析。实验结果表明,Cu-Zr基金属玻璃的形成能力受到Nb的加入和吸铸直径的影响:相对于直径为2mm的金属玻璃,直径为3mm及5mm的金属玻璃的塑性和压缩强度都有明显的降低,其综合性能明显下降,表明直径对合金性能的影响相当大。     

等温时效过程中金属玻璃的结构弛豫

本文针对目前对于金属玻璃结构弛豫规律的不同看法,结合a—Pd_(8o)Si_(20)的等温内耗测量,通过分析、研究提出了我们的看法。同时,提出了金属玻璃在等温时效过程中结构弛豫的非线性动力学特征,并导出了金属玻璃在等温时效过程中内耗随时间变化的半经验公式。     

神奇的“金属玻璃”

①金属玻璃是一种特殊的合金材料。通常金属原子都是有序排列的品体结构．而在金属玻璃中．原子的排列如同液体或者玻璃一样杂乱无章。虽然从严格意义上来说．金属玻璃并不是液体．但是由于它没有固定的外形．可以像液体一样随意流动．所以人们喜欢形象地称之为“液态金属”。     

用玻璃与金属制成的功能梯度材料

用玻璃与金属制成的功能梯度材料日本住友煤矿有限公司成功地用玻璃和金属合成了一种功能梯度材料（ＦＧＭ）。玻璃和金属是两种截然不同的物质，因此，通过创立一种同时使用高压和电流熔化金属和玻璃的粉末的电火花等离子熔化工艺（ＳＰＳ），使这种材料的合成成为可能。...     

神奇的金属玻璃

一根直径4毫米粗的合金丝竞可以悬吊起3吨的重物;这种合金浸在强酸、强碱性液体中,仍能完好无损;具有接近陶瓷的硬度却在一定温度能像液体那样流动。这就是金属玻璃,一种神奇的新材料。一、金属玻璃的概念金属玻璃(又称非晶合金)及其复合材料是采用现代冶金技术合成的一种比普通金属强度高得多,且具有高弹性低模量等特性的新型合金材料。金属玻璃中的"金属",是指这种新型合金材料是由金属     

希望和困境——金属玻璃制备方法的回顾和展望

一、什么是金属玻璃? 今天,人们把信息,能源,材料,称之为新技术革命的三大支柱。离开材料,任何新产品的开发都是一句空话。在材料科学的百花园中,有一株光彩夺目的幼苗,特别受人瞩目。它就是金属玻璃,或玻璃态金属。金属玻璃是指非晶态金属材料。它是非晶态材料中很重要的一类。此外还有很多种非晶态料材也很有用。例如:非晶态半导体材料,非晶态超导材料,非晶态高分子材料,以及传统的非晶态硅酸盐材料等等。过去的很长一段时间内,人们曾误认为,只有无缺陷的完美的理想晶体,才具有最优异的性能。这方面的长期追求,形成了传统     

玻璃和金属的导电性能与温度的关系

江西永新芦溪中学刘星同学提出为什么玻璃在加热的条件下可以导电,而金属在加热时导电性能又大大减弱的问题.我想,刘星同学在提这个问题的时候,已经知道在通常条件下,即在常温下玻璃是不导电的,而金属是导电的.要回答刘星同学的问题,首先要明白为什么在常温下金属是导体(导电性能好的物体),而玻璃是绝缘体(不导电的物体).     

大观园

海底火山有金矿 日本科学家发现,南太平洋海底火山周围蕴藏着丰富的金矿和其他矿藏。金属"玻璃" 美国研制出一种称之为"金属玻璃"的钢材,它重量轻、弹性好、抗腐蚀、有磁性,强度是普通钢材的两倍。     

气相色谱金属毛细管柱

本文阐述了当今玻璃、石英类常用毛细柱管材存在的各种问题,以及金属毛细管柱在这些方面的潜在优势,并着重对金属毛细管内壁去活方法进行了评述,介绍了一种新的金属毛细管惰化方法,提出金屑毛细管柱是一种具有发展前途的色谱柱。     

金属，“液态”的！

还记得《终结者2》里那个大反派吗？他是个液态金属机器人,身体呈液态状,中枪后,被子弹打穿的洞很快会被补平,可以随意变形。虽说这是科幻电影的情节,但在现实世界中,的确存在液态金属。 我们知道,自然界中有些金属,例如汞、镓等,在常温下呈液体状态,本身就是液态的。但我们这里要说的液态金属,指的是将玻璃的制备工艺引入到金属或合金当中,使之以较高的冷却速率固化而成的金属,又称金属玻璃,也称非晶材料。     

Zr52.5Al10Ni10Cu15Be12.5 大块金属玻璃的高温宏观硬度

The hot hardness behavior of Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glass is studied from ambient temperature to the temperature over Tx （the onset crystallization temperature） using a hot macro-hardness tester and scanning electron microscopy （SEM）. The results show that the hot hardness behavior of Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glass can be classified into 4 zones： the glassy zone in which the hardness almost linearly decreases with the increase of temperature, the viscoelastic zone in which the hardness is nearly unchanged, the viscous flow zone in which the hardness quickly tends towards near zero with temperature, and the crystallization zone in which the hardness sharply increases. The high temperature deformation behavior and the easy processable deformation region for bulk metallic glasses are also discussed on the basis of the hot marco-hardness.     

Zr_(52．5)Al_(10)Ni_(10)Cu_(15)Be_(12．5)大块金属玻璃的高温宏观硬度

The hot hardness behavior of Zr_(52.5)Al_(10)Ni_(10)Cu_(15)Be_(12.5) bulk metallic glass is studied from ambient temperature to the temperature over T_x (the onset crystallization temperature) using a hot macro-hardness tester and scanning electron microscopy (SEM).The results show that the hot hardness behavior of Zr_(52.5)Al_(10)Ni_(10)Cu_(15)Be_(12.5) bulk metallic glass can be classified into 4 zones:the glassy zone in which the hardness almost linearly decreases with the increase of temperature,the viscoelastic zone in which the hardness is nearly unchanged,the viscous flow zone in which the hardness quickly tends towards near zero with temperature,and the crystallization zone in which the hardness sharply increases.The high temperature deformation behavior and the easy processable deformation region for bulk metallic glasses are also discussed on the basis of the hot marco-hardness.     

Determination of accurate theoretical values for thermodynamic properties in bulk metallic glasses

Deviation values of specific heat difference ACp, the Gibbs free energy difference AG, enthalpy dif- ference AH, and entropy difference AS between the supercooled liquid and corresponding crystalline phase produced by the linear, hyperbolic, and Dubey＇s expres- sions of ACp and the corresponding experimental values are determined for sixteen bulk metallic glasses （BMGs） from the glass transition temperature Tg to the melting temperature Tm. The calculated values produced by the hyperbolic expression for ACp most closely approximate experimental values, indicating that the hyperbolic ACp expression can be considered universally applicable, compared to linear and Dubey＇s expressions for ACp, which are accurate only within a limited range of condi- tions. For instance, Dubey＇s ACp expression provides a good approximation of actual experimental values within certain conditions （i.e., ~ = ACg/AC~ 〈 2, where ACpg and ACp represent the specific heat difference at temperatures Tg and Tm, respectively）.     

生物医用金属材料的研究进展

介绍了医用金属材料目前的研究现状、性能和应用,指出了医用金属材料应用中目前存在的主要问题,阐述了近年来生物医用金属材料的新进展,提出镁及镁合金材料的应用是生物医用金属材料的发展方向。     

Perspectives on the metallic interconnects for solid oxide fuel cells

The various stages and progress in the development of interconnect materials for solid oxide fuel cells (SOFCs) over the last two decades are reviewed. The criteria for the application of materials as interconnects are highlighted. Interconnects based on lanthanum chromite ceramics demonstrate many inherent drawbacks and therefore are only useful for SOFCs operating around 1000 ℃. The advance in the research of anode-supported flat SOFCs facilitates the replacement of ceramic interconnects with metallic ones due to their significantly lowered working temperature. Besides, interconnects made of metals or alloys offer many advantages as compared to their ceramic counterpart. The oxidation response and thermal expansion behaviors of various prospective metallic interconnects are examined and evaluated. The minimization of contact resistance to achieve desired and reliable stack performance during their projected lifetime still remains a highly challenging issue with metallic interconnects. Inexpensive coating materials and techniques may play a key role in pro moting the commercialization of SOFC stack whose interconnects are constructed of some current commercially available alloys. Alternatively, development of new metallic materials that are capable of forming stable oxide scales with sluggish growth rate and sufficient electrical conductivity is called for.     

刚性玻璃和易碎玻璃的分子动力学差别

利用分子动力学模拟数据，给出了二氧化硅玻璃和氟锆硼玻璃的速度自相关函数，递归函数和红外振动频率等方面的结果，分析和讨论了刚性玻璃和易碎玻璃的分子动力学差别。定性解释了高压下刚性玻璃变脆的实验事实。     

Mg60Cu30Y10合金微观结构的第一性原理研究

该文利用第一性原理计算对Mg60Cu30Y10合金进行了模拟研究,分析Mg60Cu30Y10合金的几何特征：双体关联函数、三体关联函数、空间关联系数,并利用Voronoi拼砌方法对Mg60Cu30Y10合金的结构做了分析.计算发现Mg60Cu30Y10合金中Mg原子的环境与晶态Mg2Cu中的环境类似,而Cu-Y、Y-Y之间的关联对于合金的性能起着决定性的作用.     

金属针布耐磨性实验系统研制

阐述了金属针布磨损实验的基本原理,并对其特点进行了分析。依据金属针布实际工况,设计了金属针布耐磨性实验系统,介绍了金属针布的磨损测试方法。