冷轧工艺对Ni5W合金基带织构的影响研究

根据涂层超导应用对Ni5W合金基带织构的要求,分析研究了轧制方式、轧制工艺润滑、轧制速度等对Ni5W合金基带轧制形变织构及再结晶立方织构的影响,研究发现,往复轧制避免了不利于形成再结晶立方织构的其他冷轧取向的产生,进而在Ni5W合金基带中获得较多的C型和S型取向,利于退火过程中获得锐利的再结晶立方织构,对比分析了非润滑轧制和润滑轧制的再结晶晶界分布情况,发现非润滑轧制较润滑轧制产生的孪晶界含量少,且晶界质量比较高,并对3种不同轧制速度的轧制结果进行了分析,得出5 m.min-1为最佳的轧制速度。提出了相应的优化轧制工艺,为轧制基带的织构控制和性能优化提供参考,最终冷轧和退火后获得了长度为20 m,厚度为～63μm,立方织构含量达～99%(10°),性能均匀的Ni5W合金基带,为Ni5W合金基带长带的产业化生产奠定了基础。     

预退火温度对Ni-5%W合金立方再结晶织构的影响

作为制备高温超导涂层导体的金属镍基带,需要具有良好的立方织构,而轧制变形量和退火温度对金属镍基体立方织构的形成有很大的影响。采用电子背散射衍射(EBSD)技术研究了不同预退火温度对冷轧形变量为89%的Ni-5%W(原子分数)合金立方再结晶织构的影响。样品先在300和670℃预退火1 h,然后经10%小变形量冷轧,最后在900℃退火1 h。结果表明:预处理温度对于立方再结晶织构的形成有重要的影响,经300℃预回复和670℃部分再结晶退火之后的样品在最终退火后都形成了较高含量的立方织构,且预退火温度对立方晶粒的形核、数量和尺寸有重要作用,经部分再结晶退火之后的样品在最终退火后形成的立方织构含量明显高于经预回复的样品。分析认为,预回复和部分再结晶样品经小变形轧制后,使立方取向晶粒回复加快,增加了立方取向晶粒形核的优势,从而促进立方再结晶织构含量的增加。与此同时,由于部分再结晶预退火比预回复退火形成的立方晶核多,再经小变形量轧制后,通过尺寸优势和应变诱导晶界移动机制(SIBM),部分再结晶预退火得到更多的立方晶粒。     

不同厚度低温渗氮型取向硅钢初次再结晶组织、织构差异分析

以0.27 mm、0.23 mm和0.20 mm三种厚度且磁性能都较好的取向硅钢样品为研究对象,通过EBSD技术对其对应的初次再结晶晶粒尺寸及织构进行研究,从而探索不同板厚度对应的最佳初次再结晶组织和织构是否存在异同。结果表明：三种厚度对应的最佳一次再结晶晶粒平均尺寸均在20～22μm范围内,沿板厚侧面的平均晶粒尺寸基本接近,约为21.4μm; 0.27 mm的中心层区域的平均晶粒尺寸比表层更大,而随厚度继续减小,表层和中心层平均晶粒尺寸逐渐接近。随板厚度的减小,初次再结晶织构增强,主要织构{114}〈481〉、{111}〈112〉以及{100}〈021〉织构均在一定程度上增强,其中{114}〈481〉织构的强度又显著高于其他织构;{114}〈481〉组分面积百分比增加,Goss以及{210}〈001〉组分减少。在这三种厚度样品中,表层区域的Goss、{210}〈001〉和{114}〈481〉组分比例都高于中心层,{100}〈021〉以及黄铜组分比例都低于中心层。随着厚度的减薄,表层和中心层区域的{114}〈481〉、{111}〈112〉织构以及中心层区域的{100}〈021〉织构都明...     

涂层导体用Ni4WV合金基带的成分与织构研究

通过真空感应熔炼出Ni4WxV(x=2,4,6)合金,采用轧制辅助双轴织构基带技术制备出厚度200μm的合金基带。测量合金基带的磁性能和屈服强度;采用X射线衍射技术(XRD)及电子背散射衍射技术(EBSD)分析比较不同成分合金基带的冷轧织构和再结晶织构,并与Ni5W合金基带进行比较,得出综合性能更优的成分。结果表明,Ni4W2V合金基带综合性能最佳,其屈服强度为150.7 MPa,与Ni5W合金基带相当;常温下饱和磁化强度为Ni5W合金基带的55%,立方织构含量为56%(30°),极具研究前景。     

涂层导体用立方织构Ni基带的电化学抛光

大变形量加工及随后再结晶热处理制备的立方织构Ni及其合金带材广泛用于YBa2Cu3O7-x(YBCO)涂层导体的基带。隔离层及YBCO涂层的生长要求基带提供光滑的表面。但由于国内轧制水平的限制,轧制-再结晶基带的表面无法满足工艺使用的要求,必须通过表面处理改善基带表面质量。选用电化学抛光工艺提高基带表面质量,主要研究抛光液成分和抛光电流密度对抛光质量的影响。结果表明,磷酸含量85%,甘油含量15%,添加剂含量4 ml.L-1时,抛光效果最好。抛光后基带的最大表面粗糙度小于9 nm。     

3.10％Si高牌号冷轧无取向硅钢组织织构演变的研究

以3.10%Si高牌号无取向硅钢为研究对象,对其热轧板、常化板、冷轧板和退火板进行了组织、织构分析。结果表明,热轧板组织沿厚度方向分布不均匀,从表层到芯部变化较大,分层明显,表层织构主要为{111}和{112};常化板组织在厚度方向与热轧板类似,但晶粒明显长大,组织均匀性较好,平均晶粒尺寸为119μm,织构组分与热轧板基本相当;冷轧板为沿着轧制方向伸长的纤维组织;退火板为再结晶组织,平均晶粒尺寸为151μm,{001}100织构组分含量最高。     

CSP无取向电工钢50 W600组织及织构演变研究

文章研究了CSP无取向电工钢50W600在热轧、冷轧、退火过程组织、织构演变情况,研究结果表明:铸坯为柱状晶组织;热轧板沿厚度方织构是不均匀的,表层主要织构为黄铜织构;脱碳退火板为再结晶组织,平均晶粒尺寸50μm,主要为γ纤维织构。     

Ni-Cu-W合金薄带的再结晶织构与性能研究

在采用轧制辅助双轴织构技术(RABi TS)制备二代高温超导涂层YBa2Cu3O7-x(YBCO)导线的工艺中,金属基带的织构、物理和力学性能一直是备受关注的问题。本文基于合金元素与织构、居里温度和屈服强度相关性,设计了能满足轧制辅助双轴织构技术制备超导线的Ni-32%Cu-3%W合金,采用冷坩埚悬浮熔炼技术冶炼了合金铸锭,铸锭经锻造、热轧、冷轧和再结晶退火,最终获得了厚度为80μm的织构薄带。采用背散射电子衍射(EBSD)技术表征了合金再结晶织构,利用高分辨透射电镜(HRTEM)分析了显微组织结构。结果表明:经过98%冷轧的Ni-32%Cu-3%W合金薄带再结晶退火后可以获得99%的立方织构份额,在950~1100℃温度范围内,立方织构份额随退火温度升高或退火时间的延长而增加;合金居里温度为105 K,在室温下的屈服强度σ0.2%为184 MPa,表明Ni-32%Cu-3%W合金薄带可以替代Ni-5%W合金基带用作二代高温超导涂层的衬底材料。     

超高纯CuMn合金材料微观组织和织构演变研究

当前超大规模集成电路(ULSI)的特征尺寸已经步入纳米范围,随着特征尺寸的减小,铜互连面临着严重的可靠性问题,采用合金化手段可有效抑制晶界附近的电迁移。因而本文主要研究超高纯铜锰合金材料,通过金相(OM)、电子背散射衍射(EBSD)等分析手段研究超高纯铜锰合金材料塑性形变过程和热处理过程中铜锰合金试样的微观组织变化和轧制、再结晶织构变化。实验结果表明:经过对塑性变形试样的分析后发现,试样微观组织主要由许多破碎的小晶粒及亚晶组成,同时试样中存在典型的轧制织构并且存在大量的小角度晶界。经过退火热处理后,试样的微观组织比较均匀,晶粒细小,晶粒尺寸大约为10.7μm;典型轧制织构组分下降比较明显,典型再结晶织构组分上升,但大部分晶粒处于随机取向,试样退火热处理后几乎全部为大角度晶界。     

铈对无取向硅钢再结晶组织及织构的影响

以无取向硅钢为研究对象,在实验室制备添加0.002%(质量分数)铈和不添加铈的两种实验钢。采用光学显微镜观察了再结晶组织并采用imagetool统计了再结晶晶粒尺寸,采用XRD分析了试样的再结晶织构。结果表明,铈阻碍了无取向硅钢的再结晶过程。铈的加入使无取向硅钢的最终晶粒尺寸增大,不加铈的试样平均晶粒尺寸为13.74μm,而加铈的试样为18.38μm。加入铈后无取向硅钢退火再结晶织构类型变化不大,整体密度水平下降,{111}再结晶织构组分强度降低。     

Prenucleation Induced by Crystalline Substrates

Prenucleation refers to the phenomenon of atomic ordering in the liquid adjacent to the substrate/liquid interface at temperatures above the liquidus. In this paper, we have systematically investigated and holistically quantified the prenucleation phenomenon as a function of temperature and the lattice misfit between the substrate and the solid, using molecular dynamics (MD) simulations. Our results have confirmed that at temperatures above the liquidus, the atoms in the liquid at the interface may exhibit pronounced atomic ordering, manifested by atomic layering normal to the interface, in-plane atomic ordering parallel to the interface, and the formation of a 2-dimensional (2D) ordered structure (a few atomic layers in thickness) on the substrate surface. Holistic quantification of such atomic ordering at the interface has revealed that the atomic layering is independent of lattice misfit and is only slightly enhanced by reducing temperature while both in-plane atomic ordering and the formation of the 2D ordered structure are significantly enhanced by reducing the lattice misfit and/or temperature. This substrate-induced atomic ordering in the liquid may have a significant influence on the subsequent heterogeneous nucleation process.     

Impregnation of Tungsten-Carbide Substrates with Low-Carbon Steel

The interaction of tungsten carbide and low-carbon steel in contact and contact-free is investigated in systems with contact and contact-free heating. Substrates of pressed tungsten-carbide powder sintered in a vacuum furnace are impregnated with low-carbon steel of specific chemical composition. A high-speed video recording of the process permits measurement of the contact wetting angle at any time during the experiment. The experiment is conducted at the Center for High-Temperature Studies, Foundry Research Institute, Krakow, Poland. The microstructure of the substrates obtained is investigated. The chemical composition of the reaction products is studied by means of a Jeol JSM-6460 LV scanning electron microscope. All the samples are successfully impregnated. The same structure is observed throughout the substrate cross section. It consists of three phases: tungsten-carbide grains; and iron–tungsten–carbon compounds with different iron content (86.72 and 22.86–23.68%). At the edges adjacent to the upper face, large quantities of the iron–tungsten–carbon compound with 22.86–23.68% Fe may be observed. This is explained in that such regions are impregnated last, and the iron dissolves the carbide more than in other regions. At points of direct substrate–iron interaction, grains of tungsten carbide are clearly identified; they are bound together by iron-based melt (with different iron content in different phases). Partial coverage of the sample surface by an iron film is seen on both samples at the horizontal face of the substrate adjacent to the impregnation region. The edges of the substrate’s horizontal face are completely covered with iron film, under which lie tungsten-carbide grains. Despite the use of different methods to study the interaction of tungsten carbide with low-carbon steel (contact and contact-free heating), no great difference in sample structure is observed.     

钛合金基体上阻燃涂层的研究进展

介绍了航空发动机上钛燃烧及其原因。概括了国内外钛合金基体上阻燃涂层的研究概况,重点对钛合金基体上阻燃涂层的应用、阻燃性能的检测方法和阻燃机理进行了总结。并对国内该类涂层的研究提出了一些建议。     

Degradation of Toxaphene by Zero-Valent Iron and Bimetallic Substrates

The pesticide, toxaphene, is a major environmental concern and has been reported to be harmful, especially via skin contact, ingestion, or inhalation. Although now banned, it persists in nature. The results of this research showed that toxaphene in an aqueous solution was degraded by dechlorination when contacted with Fe0 and bimetallic substrates. This degradation displayed a power-law relationship with a decrease of toxaphene concentration over time. Toxaphene contacted with Fe0 produced a degradation rate value, ?kTox [ln(h)]?1, of 0.088 for a solution-to-mass ratio of 4:1 and 0.113 for a 2:1 ratio. Doubling the initial concentration of toxaphene for a volume-to-mass ratio of 4:1 decreased the degradation rate and resulted in a ?kTox value of 0.061. Bimetallic substrates including nickel-plated Fe0 and copper-plated Fe0 had degradation values of 0.219 and 0.245, respectively. A chloride mass balance indicated that nearly all of the toxaphene in the solution had been dechlorinated; as the chloride concentration in the solution increased over time, the toxaphene concentration decreased. The increase of chloride ions in the solution displayed a logarithmic relationship over time for all of the substrates contacted with toxaphene.     

陶瓷基体热喷涂涂层的研究进展

由于表面改性的需要,陶瓷基体对热喷涂涂层方案的需求也在日益增加.根据基体结构和性能的不同,需要开发特殊的基体相关的制备概念.本文展示一些在烧结氮化硅和AlN陶瓷上沉积涂层的概念.使用传统的喷砂工艺处理的基体近表面区域粗糙度低并会带来损害.作为替代方法,激光刻蚀被用来改变陶瓷基体的热喷涂表面特性.通过选择适当的激光刻蚀参数和喷涂方法,成功地制备了与陶瓷基体具有良好结合性能的大气等离子喷涂（APS）和悬浮液超音速火焰喷涂（suspension-HVOF A12O3）涂层.     

Substrates of energy metabolism attenuate methamphetamine-induced neurotoxicity in striatum

High doses of methamphetamine (METH) produce a long-term depletion in striatal tissue dopamine content. The mechanism mediating this toxicity has been associated with increased concentrations of dopamine and glutamate and altered energy metabolism. In vivo microdialysis was used to assess and alter the metabolic environment of the brain during high doses of METH. METH significantly increased extracellular concentrations of lactate in striatum and prefrontal cortex. This increase was significantly greater in striatum and coincided with the greater vulnerability of this brain region to the toxic effects of METH. To examine the effect of supplementing energy metabolism on METH-induced dopamine content depletions, the striatum was perfused directly with decylubiquinone or nicotinamide to enhance the energetic capacity of the tissue during or after a neurotoxic dosing regimen of METH. When decylubiquinone or nicotinamide was perfused into striatum during the administration of METH, there was no significant effect on METH-induced striatal dopamine efflux, glutamate efflux, or the long-term dopamine depletions measured 7 days later. However, a delayed perfusion with decylubiquinone or nicotinamide for 6 h beginning immediately after the last METH injection attenuated the METH-induced striatal dopamine depletions measured 1 week later. These results support the hypothesis that the compromised metabolic state produced by METH administration predisposes dopamine terminals to the neurotoxic effects of glutamate, dopamine, and/or free radicals.     

AlN陶瓷基片烧结曲线的研究与优化

研究了AlN陶瓷基片烧结曲线中液相烧结升温速率、保温时间、烧结温度对基片性能的影响。测定不同液相烧结升温速率下试样的翘曲度,确定最佳升温速率范围为0.2~0.5℃/min;同时,根据不同保温时间下试样密度的变化优选保温时间为5h,并协调出最高烧结温度为1 830℃。通过对比烧结曲线优化前后AlN陶瓷基片主要性能及组织结构,结果表明烧结曲线优化后效果明显。     

Fex-C1-x/Si颗粒膜的巨磁电阻效应

利用激光脉冲沉积（PLD）方法制备了沉积于硅基片上的掺杂过渡金属的非晶碳膜结构Fex-C1-x/Si。Fex-C1-x/Si的磁电阻（MR）可正可负，随温度而变化。当温度T〈258K时，Fe0．011-C0.989／Si的MR为负值；当258K〈T〈340K时，该材料的MR为正值，在室温磁场为1T时，该材料的正MR可以大于20％。且在不同的温度范围中，该材料的MR和外加磁场的依存关系呈现出不同的特点：在T=280和300K时，当磁场小于1T时，MR随磁场的增加而快速增加，之后随磁场的继续增加MR增加开始变得缓慢；在T=350K时，MR近似以磁场的B^1.5。的规律变化；而在T=30K时，MR为负值且其大小随磁场的增加而减小。利用双通道模型对该MR效应进行了初步解释。     

Fracture and Delamination of Chromium Thin Films on Polymer Substrates

New emerging technologies in the field of flexible electronic devices require that metal films adhere well and flex with polymer substrates. Common thin film materials used for these applications include copper (Cu) with an adhesion interlayer of chromium (Cr). Copper can be quite ductile and easily move with the polymer substrate. However, Cr is more brittle and fractures at lower strains than Cu. This study aims to examine the fracture and subsequent buckling and delamination of strained Cr films on polyimide (PI). In-situ scanning electron microscope (SEM) straining is used to systematically study the influence of film thickness on fracture and buckling strains. Film fracture and delamination depend on film thickness, and increases in crack and buckle density with decreasing thickness are explored by a shear lag model.     

An Epitaxial Model for Heterogeneous Nucleation on Potent Substrates

In this article, we present an epitaxial model for heterogeneous nucleation on potent substrates. It is proposed that heterogeneous nucleation of the solid phase (S) on a potent substrate (N) occurs by epitaxial growth of a pseudomorphic solid (PS) layer on the substrate surface under a critical undercooling (ΔT _c). The PS layer with a coherent PS/N interface mimics the atomic arrangement of the substrate, giving rise to a linear increase of misfit strain energy with layer thickness. At a critical thickness (h _c), elastic strain energy reaches a critical level, at which point, misfit dislocations are created to release the elastic strain energy in the PS layer. This converts the strained PS layer to a strainless solid (S), and changes the initial coherent PS/N interface into a semicoherent S/N interface. Beyond this critical thickness, further growth will be strainless, and solidification enters the growth stage. It is shown analytically that the lattice misfit (f) between the solid and the substrate has a strong influence on both h _c and ΔT _c; h _c decreases; and ΔT _c increases with increasing lattice misfit. This epitaxial nucleation model will be used to explain qualitatively the generally accepted experimental findings on grain refinement in the literature and to analyze the general approaches to effective grain refinement.