Sm2(Fe,Al,Zr)17C1.5合金微结构与磁性能的关系

用Ｘ射线衍射仪,振动样品磁强计,扫描电镜及透射电镜对Ｓｍ２Ｆｅ１５．３Ｚｒ０．２Ａｌ１．５Ｃ１．５合金的微结构和磁性进行了研究。合金主要由２／１７相、α－Ｆｅ相和ＺｒＣ要组成。     

金属基复合材料的界面分析

用透射电镜、扫描电镜、Ｘ射线能谱仪和电子探针研究了碳化硅颗粒（ＳｉＣｐ）增强Ａｌ２０１４复合材料的微观结构和界面。鉴定了界面上和基体中三种主要的沉淀相：ＣｕＡｌ２、Ｃｕ２Ｍｇ８Ｓｉ６Ａｌ５、（Ｍｎ，Ｆｅ）３ＳｉＡｌ１２和高温下形成的条状Ａｌ４Ｃ３。试验指出，碳化硅和基体间的界面上没有Ｓｉ和Ａｌ的相互扩散，并观察分析了ＳｉＣｐ／Ａｌ２０１４界面周围的无析出带和高密度位错     

急冷Al—Fe—V—Si—Mu合金的穆斯堡尔谱研究

利用穆斯堡尔谱和Ｘ射线和衍射研究了４种Ａｌ－Ｆｅ－Ｖ－Ｓｉ－Ｍｕ合金的Ｆｅ的原子组态。结果表明，添加混合稀土元素后抑制了基体合金Ａｌ－Ｆｅ－Ｖ－Ｓｉ中α－Ａｌ１３（Ｆｅ，Ｖ）３Ｓｉ弥散粒子相的析出；当稀土含量６ａｔ％时，形成了Ａｌ－Ｆｅ－Ｖ－Ｓｉ－Ｍｕ非晶态，采用Ｖｏｉｇｔ基函数作了穆斯堡尔谱的合理拟合和分析。     

易潮解化合物AlCl3和FeCl3在载体表面的分散状态及分散量

易潮解化合物ＡｌＣｌ３和ＦｅＣｌ３在载体表面的分散状态及分散量宗越潘晓民段连运＊谢有畅（北京大学物理化学研究所，北京１００８７１）关键词氯化铝，氯化铁，氧化铝，分散状态，分散阈值，Ｘ射线衍射无水ＡｌＣｌ３和无水ＦｅＣｌ３同属Ｌ酸，在酸催化中起着重要的...     

急冷Al－Fe－V－Si－Mm合金的穆斯堡尔谱研究

利用穆斯堡尔谱和Ｘ射线衍射研究了４种Ａｌ－Ｆｅ－Ｖ－Ｓｉ－Ｍｍ合金的Ｆｅ原子组态。结果表明，添加混合稀土元素后抑制了基体合金Ａｌ－Ｆｅ－Ｖ－Ｓｉ中α－Ａｌ１３（Ｆｅ，Ｖ）３Ｓｉ弥散粒子相的析出；当稀土含量高达６ａｔ％时，形成Ａｌ－Ｆｅ－Ｖ－Ｓｉ－Ｍｍ非晶态，采用Ｖｏｉｇｔ基函数作了穆斯堡尔谱的合理拟合和分析。     

煤裂解过程中负载铁化学形态的变化

应用ＥＸＡＦＳ、ＸＡＮＥＳ和ＸＲＤ方法研究了褐煤中负载铁在裂解过程中化学形态的变化规律。结果表明，在载ＦｅＣｌ３．６Ｈ２Ｏ煤中，铁与煤表面碳－氧官能团发生强烈的相互作用。随热处理温度的升高，铁化学形态以如下顺序递变：高分散Ｆｅ－Ｏ／Ｃ络合物，超细ＦｅＯＯＨ，晶态Ｆｅ３Ｏ４，晶还原态铁（α－Ｆｅ，（Ｆｅ，Ｃ））《     

NdCl3-FeCl3-石墨层间化合物的XPS研究

通过熔盐交换法合成了ＮｄＣｌ３－ＦｅＣｌ３－ＧＩＣ,采用Ｘ射线电子能谱（ＸＰＳ）分析插入剂在石墨层间的存在形式,并测定了试样中Ｎｄ,Ｆｅ,Ｃｌ和Ｃ的相对含量。ＮｄＣｌ３－ＦｅＣｌ３－ＧＩＣ中Ｆｅ２ｐ的结合能为７１１．２０－７１０．３ｅＶ,Ｎｄ３ｄ的结合能为９８３．２０－９８３．０８ｅＶ,并发现Ｆｅ在石墨层ｅ＾３＋,Ｆｅ＾２＋形式存在。     

NdCl3-FeCl3-石墨层间化合物的合成

采用熔盐交换法成功地合成了ＮｄＣｌ３ＦｅＣｌ３ＧＩＣ, 用ＸＲＤ 技术和Ｘ射线能谱仪（ＥＤＳ） 对其层间结构及各元素的相对含量进行了表征。研究表明, 其结构为２,３ ,４ 阶混合结构,３ 阶ＮｄＣｌ３ 的特征层间距为１－６５３６ ±０－００２４ ｎｍ , 并探讨了稀土氯化物石墨层间化合物的形成机制。     

FeCrAlNbTiRE电热合金相结构研究

用Ｘ射线衍射法和模拟粉晶衍射图的程序ＰＯＷＤ１２，研究了掺稀土的ＦｅＣｒＡｌＮｂＴｉＲＥ电热合金淬火和缓冷状态的相结构，所得结果如下：它们分别是ａ－Ｆｅ型无序固溶体和（Ｆｅ、Ｒｍ）３（Ｃｒ、Ａｌ）有序固溶体，因而前者相结构是体心立方点阵，后者出现超点阵峰，是简单立方点阵，而且后者的晶胞参数和体积分别是前者的２和８倍。     

钇对Fe-Cr-Al合金氧化膜粘附性的影响

利用热重分析,扫描电镜及能谱分析等手段研究了合金中弥散分布的Ｙ,Ｙ２Ｏ３及离子注入Ｙ＾＋对Ｆｅ－２３Ｃｒ－５Ａｌ合金１１００℃恒温氧化行为的影响。不含Ｙ的Ｆｅ２３Ｃｒ５Ａｌ合金氧化膜起皱,长时间氧化后冷却过程中膜发生开裂剥落。合金离子注入１＊１０＾１７Ｙ＾＋／ｃｍ＾２后氧化膜粘附性得到了改善。合金中加入弥散的Ｙ或Ｙ２Ｏ３改变了氧化膜形貌,膜平坦致密,不开裂剥落,不含Ｙ的Ｆｅ２３Ｃｒ５Ａｌ合金氧化膜皱褶形貌的形成及膜发生剥落的原因与氧化膜生长机制及合金中Ｓ的界面偏聚有关,Ｙ提高Ｆｅ－Ｃｒ－Ａｌ合金氧化膜粘附性的原因主要在Ｙ易与Ｓ形成稳定的硫化物,从而阻止了Ｓ在膜／合金界面偏聚。Ｙ提高Ａｌ２Ｏ３膜粘附性的原因还在于改变了Ａｌ２Ｏ３膜的生长机制。     

Deposition and characterization of TiAlSiN coatings prepared by hybrid PVD coating system

TiAlSiN coatings with different Si contents were deposited on silicon and high‐temperature alloy by using a hybrid physical vapor deposition coating system, where the cathodic arc ion plating was combined with a twin target mid‐frequency magnetron sputtering. The chemical composition, microstructure, cross‐sectional structure and morphology were carried out by X‐ray photoelectron spectroscope (XPS), X‐ray diffraction (XRD), field emission scanning electron microscopy (FESEM) and transmission electron microscope (TEM), respectively. NanoTest 600 nanomechanical system and ball‐on‐disc friction tester were used to investigate the mechanical and friction properties of TiAlSiN coatings. The worn surface of the TiAlSiN coatings and counterballs were investigated by means of surface profilometer and optical microscope. The wear rates were also measured by surface profilometer. The results showed that the Si addition did not change the coatings growth orientation, and the coating transfered into amorphous phase when the Si content reached about 13.9 at.%. The tribological properties and the hardness were improved by solid solution of Si atoms and grain boundary strengthening of SiN_x amorphous phase with moderate Si content addition. In addition, the SiNx amorphous phase improved oxidation resistance of TiAlN coating, but with a high Si content (more than 8.3 at.% in this work) the agglomeration of SiN_x amorphous phase would reduce the mechanical properties and oxidation resistance of the coating. Copyright © 2014 John Wiley & Sons, Ltd.     

杂质及铈作用下铝锂合金的应力集中敏感性

建立了评价铝锂合金应力集中敏感性的缺口敏感因子,通过测定薄板法拉伸性能,求出了不同元素及杂质含量的铝锂合金缺口敏感因子,Fe,Si,Na,K杂质均明显地增加2090及8090合金的应力集中敏感性,铈能够在一定程度上降低具有较高强度水平的合金应力集中敏感性,但在塑性水平较高的1420合金中,铈添加量超过一定限度后,反而会显著提高材料的应力集中敏感性,相对于普通铝合金,铝锂合金的应力集中敏感性一般处于较高水平,这个问题在此对类合金的实际研究中应给予充分注意。     

CoBx/Co3O4电催化剂的制备及其氧析出性能

采用NaBH4溶液处理经水热、热处理步骤制得Co3O4纳米棒,得到表面富含氧空位以及无定型CoBx的Co3O4(CoBx/Co3O4)氧析出(OER)电催化剂。利用X射线衍射(XRD)、场发射扫描电镜(FESEM)、透射电镜(TEM)、X射线光电子能谱仪(XPS)等技术表征了催化剂的物相、微观形貌、元素组成以及表面化学键结构等。通过电化学工作站测试了电极材料的OER活性、稳定性、电化学阻抗等。结果表明,经NaBH4处理后,Co3O4表面高价态Co被还原至低价态Co,最终其表面有无定型CoBx的生成,并含有大量氧空位,有效提升了OER性能。在1.0 mol·L^-1 KOH电解质溶液中,达到10 mA·cm^-2的电流密度时,CoBx/Co3O4所需的过电位由Co3O4的346 mV降至298 mV。     

Fe-Mn/Al2O3催化剂低温 NH3选择性催化还原 NO的性能

本文制备了一系列 Fe-Mn/Al2O3催化剂,并在固定床上考察了其 NH3低温选择性催化还原 NO的性能.首先考察了不同 Fe负载量制备的催化剂的脱硝性能,优选出最佳的 Fe负载量;在此基础上,研究了 Mn负载量对催化剂脱硝效率的影响;最后,对优选催化剂的抗 H2O和抗 SO2性能进行了实验研究;同时,对催化剂由于 SO2所造成的失活机制进行了考察.采用 N2吸附-脱附、X射线衍射、透射电镜、能量弥散 X射线谱、程序升温还原、程序升温脱附、X射线光电子能谱、热重和傅里叶变换红外光谱等方法对催化剂进行了表征.结果表明,最佳的 Fe和 Mn负载量均为8%,所制的8Fe-8Mn/Al2O3催化剂在150°C的脱硝效率可达近99%;同时,在整个低温测试区间(90–210°C)的脱硝效率均超过了92.6%. Fe在催化剂表面主要以 Fe3+形态存在,而 Mn主要包括 Mn4+和 Mn3+; Mn的添加提高了 Fe在催化剂表面的积累,促进了催化剂比表面积增大和活性物种分散,改善了催化剂氧化还原性能和对 NH3的吸附能力.催化剂的高活性主要是由于其具有较大的比表面积、高度分散的活性物种、增加的还原特性和表面酸性、较低的结合能、较高的 Mn4+/Mn3+和增强的表面吸附氧.此外,8Fe-8Mn/Al2O3的催化性能受 H2O和 SO2影响较小,抗 H2O和 SO2能力较强.同时,反应温度对催化剂的抗硫性有重要影响,在较低的反应温度下,催化剂抗硫性更好; SO2造成催化剂活性降低主要是由于催化剂表面硫酸盐物种的生成.一方面,表面硫酸铵盐的生成造成催化剂孔道堵塞和比表面积降低,减少了反应中的气固接触从而导致活性降低;另一方面,催化剂表面的活性物种被硫酸化,造成反应中的有效活性位减少,从而降低了催化剂活性.     

50 keV H+ ion beam irradiation of Al doped ZnO thin films: Studies of radiation stability for device applications

Thin films of Al doped ZnO (Al:ZnO) were deposited on two substrates (Si and glass) at room temperature and 300°C using DC magnetron sputtering. These films were bombarded with 50 keV H⁺ beam at several fluences. The pristine and ion beam irradiated films were analysed by X‐ray diffraction, Raman spectroscopy, scanning electron microscopy, and UV‐Vis spectroscopy. The X‐ray diffraction analysis, Hall measurements, Raman and UV‐Vis spectroscopy confirm that the structural and transport properties of Al:ZnO films do not change substantially with beam irradiation at chosen fluences. However, in comparison to film deposited at room temperature, the Al:ZnO thin film deposited at 300°C shows increased transmittance (from 70% to approximately 90%) with ion beam irradiation at highest fluence. The studies of surface morphology by scanning electron microscopy reveal that the ion irradiation yields smoothening of the films, which also increases with ion fluences. The films deposited at elevated temperature are smoother than those deposited at room temperature. In the paper, we discuss the interaction of 50 keV H⁺ ions with Al:ZnO films in terms of radiation stability in devices.     

Microstructure characteristics and shear properties of welding bonding of W/Al dissimilar metals with copper transitional layer

Commercial pure wrought tungsten and 1060 pure aluminum can be joined by using induction‐heat deposition (IHD) welding with commercial pure copper transitional layer. The microstructures of W/Cu/Al interfaces have been studied by means of scanning electron microscope, energy dispersive X‐ray, and X‐ray diffraction. Results show that copper as the transitional metal could form good interfaces with both tungsten and aluminum by IHD under proper processing parameters. The metallic bonding of W/Cu obtained by Cu and W mutual diffusing at a quite limited range without any intermetallic compounds, while eutectic of α(Al)/θ(CuAl₂) makes up Cu/Al interface. The average shear strength of W/Cu and Cu/Al interfaces are about 170 MPa and 55 Mpa, respectively, at room temperature. Copyright © 2012 John Wiley & Sons, Ltd.     

镧对ZL702合金高温性能的影响

研究了Ｌａ对ＺＬ７０２合金室温和高温力学性能的影响。Ｌａ与合金中的Ａ１,Ｓｉ,Ｆｅ等元素形成难熔的、分布于晶界的不连续网状金属间化合物,提高了合金的热稳定性。当Ｌａ的加入量为０．１０％～０．１５％（质量分数）时,可使合金获得较佳的综合力学性能。     

铈对Al-Fe基非晶合金化学短程序的影响

采用X射线衍射及DSC热分析研究了合金成分对Al Fe Ce非晶合金化学短程序的影响。发现随铁含量增加 ,合金的X射线衍射强度曲线上的预峰向大角度偏移 ;随铈含量增加 ,合金预峰向小角度偏移 ;当Fe,Ce含量变化时 ,所对应的DSC曲线存在明显差异 ,这表明合金的晶化特征发生了变化。铈的加入有利于原子间交互作用强度的增强 ,提高化合物形成趋向及稳定性 ,并有利于非晶的形成。     

Cu-Sn-P-LiMn2O4纳米复合材料镀层的XPS和AES研究

采用化学复合镀技术，在Q₂₃₅碳钢片表面制备了Cu-Sn-P-LiMn₂O₄纳米复合材料镀层。用扫描电子显微镜(SEM)观察外貌；称重法测定厚度；通过5% NaCl溶液、1% H₂S气体加速腐蚀试验、抗粘性试验及室温氧化试验等多种手段测定其性能。用X-射线光电子能谱(XPS)及俄歇电子能谱(AES)测定其价态及组成。结果表明:Cu-Sn-P-LiMn₂O₄纳米复合材料镀层的性     

Interface characteristics in diffusion bonding of Fe3Al with Cr18-Ni8 stainless steel

Fe3Al and Cr18-Ni8 stainless steel were diffusion-bonded in vacuum and a Fe3Al/Cr18-Ni8 interface with reaction layer was formed. Microstructure in the reaction layer at Fe3Al/Cr18-Ni8 interface was analyzed by means of scanning electron microscope (SEM) and electron probe micro-analyzer (EPMA). The growth of reaction layer with heating temperature (T) and holding time (t) was researched. The results indicate that FeAl, Fe3Al, Ni3Al, and alpha-Fe (Al) solid solution are formed in the reaction layer. These phases are favorable to promote the element diffusion and to accelerate the formation of the reaction layer at Fe3Al/Cr18-Ni8 interface. The growth of reaction layer obeys the parabolic law and its thickness (X) is expressed by X2 = 7.5 x 10(-4)exp(-83.59/RT)(t - t0).