稀土-过渡金属磁光介质膜的理论与特性

本文讨论了稀土-过渡金属(以下简写为 RE-TM)非晶合金膜用作磁光记录介质的理论和 TbFeCo 膜的特性。采用射频溅射技术制备出 TbFeCo 非晶垂直磁化膜。膜的垂直各向异性常数K_u 为2.94×10~(5J)/m~3,克尔旋转角θ_k 为0.24-0.29°。得到了θ_k 随过渡金属 Co 含量而变化的曲线。当 Co 在 TM 次网络中含量达50%时,θ_k 有最大值0.29°。在膜被复盖一层 SiO_2或 AlN 之后,θ_k 从0.29°提高到0.55°或1.48°。(TbFeCo+AlN)膜的θ_k 达到1.48°这样高的值,尚未见文献报导。这种膜可以直接用作磁光记录介质。     

Sol-gel法制备(BiAl)DyIG石榴石磁光记录薄膜

采用柠檬酸络合物型溶胶 凝胶法首次制备得到了具有垂直各向异性的(BiAl)DyIG石榴石磁光记录薄膜,并对材料结构和磁光性质进行了研究,结果得到石榴石磁光记录薄膜磁滞回线具有较好的矩形比,在430nm和520nm的品质因子为2°和1.5°,最佳晶化温度为675℃。     

离子束辅助沉积入射角对FexCr1-x合金薄膜微结构及磁性的影响

运用离子束辅助沉积技术在不同的离子束入射角(0°,15°,30°,45°,60°,75°)下,制备了的FexCr1-x合金薄膜(x=50,67),并对其微结构和磁性进行了研究.在两组不同成分的薄膜中,均发现仅在入射角为45°时,垂直于膜面的方向上出现了(002)择优取向,且伴随着膜面的平面磁各向异性,而在其他角度的情况下,无择优取向及平面磁各向异性获得.根据择优取向的形成机制,斜入射的离子束在沉积过程中起到了混合及沟道效应的作用.     

用射频磁控溅射法在二氧化硅衬底上制备磁光Ce∶YIG薄膜

使用射频磁控溅射法在非晶态的二氧化硅衬底上制备Ce1YIG磁光薄膜。生成的Ce1YIG薄膜为非晶态形式 ,经过后续的热处理过程 ,转变为晶化薄膜 ,在用波长为 6 30nm的激光测量时 ,薄膜的饱和法拉弟旋转系数θF 为 80 0°/mm。晶化薄膜具有很强的平行于膜面的磁化强度 ,用VSM测得晶化薄膜的居里温度为 2 2 0℃。实验结果表明 :所制备的薄膜适宜于制备波导型磁光隔离器。同时 ,这一方法为进一步研究非互易平面光波回路打下了基础     

Co-Ag颗粒膜的磁光克尔效应

采用离子束溅射法制备了Ｃｏ－Ａｇ颗粒膜,并分别在１００℃、２５０℃、４００℃、５００℃下进行了退火。利用磁光克尔谱仪、椭圆偏振光谱仪对样品的光学常数、复介电函数、磁光克尔参数在室温下进行了测量。对于Ｃｏ２０Ａｇ８０系列样品,随着退火温度的升高磁光克尔旋转角θｋ增大,且在Ａｇ的等离子振荡边附近出现了大的增强峰,峰的位置随退火温度的升高出现红移。通过理论计算分析,这种克尔效应的增强是Ａｇ等离子振荡边作     

碳/环氧复合材料多向层间拉伸强度的研究

本文系统地研究了碳/环氧复合材料多向层间(0/θ)(θ=0°,15°,30°,45°,60°,75°,90°)拉伸强度,并利用S-570扫描电镜观察了其断口形貌,同时对纤维与基体界面处的应力进行了分析。结果表明:该复合材料层间拉伸强度较少受到铺层取向的影响,而由纤维与基体的界面结合强度所控制。     

离子掺杂钇铁石榴石磁光材料研究进展

综述了钇铁石榴石型磁光材料的研究进展,以及通过离子掺杂提高单晶和薄膜材料的比法拉第旋转角、改善材料温度稳定性以及近年来受到重视并有望在磁光器件中得到广泛应用的低成本钇铁石榴石纳米晶/有机分散介质复合薄膜材料的研究进展与存在的问题,概述了目前实际使用中的磁光法拉第转子材料的应用情况,并展望了高性能磁光材料的发展。     

SmDyFeCo磁光薄膜的磁特性研究

采用射频磁控溅射方法制备了ＳｍＤｙＦｅＣｏ非晶磁光薄膜，研究了氩气压，溅射功率对ＳｍＤｙＦｅＣｏ薄膜磁特性的影响。实验表明，和ＤｙＦｅＣｏ非晶薄膜相比，ＳｍＤｙＦｅＣｏ非晶薄膜的矫顽力Ｈｃ随温度变化更为缓慢，并且具有更大的垂直磁各向异性常数，因而具有更好的记录特性，本征磁光克尔角可达０．３１，可以作为一种实用化的磁光记录介质。     

真空退火Co/Pt多层膜的结构、磁及磁光特性分析

本文用直流磁控溅射方法制备了Co／Pt多层膜,并对其进行了较为细致的真空退火处理,结果表明,适度的低温退火可增加Co／Pt多层膜的矫顽力,而并不削弱其磁滞克尔回线的矩形特征．当退火温度达到300℃以后,Co／Pt多层膜的矫顽力、垂直各向异性和克尔角将强烈下降,晶体结构的改善及应力的释放、晶粒的增长、层间原子扩散引起的Co层有效厚度减薄,进而居里温度的下降,分别是Co／Pt多层膜在低温、中温、高温退火过程中,磁及磁光性能变化的主要机制．     

光存储介质——光盘

光盘存储,采用激光束记录和读出的方式,具有高存储密度、长使用寿命等优点,适于存储声像、文娱节目、文件、书籍、照片、数字数据等几乎一切信息。光盘存储技术的关键部分之一,就是记录介质——光盘。光盘由在基体(通常是玻璃、塑料等)上镀具有光效应的薄膜制成。记录信息时,由输入信号调制的激光束,聚焦成直径亚微米大小的光斑,在旋转的光盘上扫描,把信息以一连串“点”的形式沿螺线轨迹存储在记录介质膜层内。在这些“点”处,也即激光已照射处,     

The Research of Anti-Wear Properties of Organomolybdenum Compounds in the Engine Oils

A four-ball tester was used to evaluate the anti-wear performance of three kinds of organomolybdemun compounds in the engine oils, i. e., molybdenum dialkyldithiophosphate (MoDDP), molybdenum dialkyldithiocarbamate ( MoDTC), and sulphur and phosphorus freeorganomolybdeum (Molybdate). The results indicate that a low concentration of MoDDP doesn' t improve the anti-wear properties of the commercial engine oils, but a high concentration of MoDDP can obviously improve the anti-wear properties and the load-carrying capacity of the engine oils. MoDTC doesn' t improve the antiwear properties of the engine oils, but worsens the anti-wear properties of the oils. Signifi can timprove ment of frictional and wear characteristics is obtained with Molybdate added in the commercial engine oils and the formulated oils.     

Certification Becomes Important for the I Quality; and Safety Supervision of the Chinese Liquor Sector

The end of 2007, over 200 unit products of more than 80 Chinese firms have passed the quality grade certification for liquor products. These products involve distilled spirits, beer, wine, yellow wine, fruit syrup wine and others, and cover over 80% of the national top-branded liquor products.……     

Deposition and Coating Properties on CVD Tungsten

Surface characterization and microstructure studies are performed on chemical vapor deposited (CVD) tungsten coating. There is about 2 μm thickness diffusion layer of tungsten in the molybdenum substrate. The thermal shock test shows tungsten coating has good adhesion with molybdenum substrate, but the elements of oxygen and carbon in the tungsten coating have the bad affection to the adhesion. The result of high-temperature diffusion experiment is the diffusion rate from molybdenum substrate to tungsten coating is faster.     

Analysis of marine hydrobiont lipid extracts as possible cryoprotective agents

We studied a combined effect of the cryoprotectants both of lipid and carbohydrate origin at the presence of DMSO or without it on cell viability and the RNA synthesis in the embryonic mollusc and echinoderm cell cultures obtained at different developmental stages. Cryoprotective properties of exogenous lipids correlated with their thermotropic behavior. Lipid extracts from marine hydrobiontes, which thermal transitions are characterized by relatively small part of calorimetric thermogram area lying at temperatures above 0 °C (6–18%), were found to possess a considerable cryoprotective activity. The results are discussed in relation to the prediction of the cryoprotective activity of lipid extracts for marine animal cells. In addition, it was found that marine invertebrate cells can be cryopreserved without DMSO at the presence of trehalose and lipid extracts of some marine hydrobiontes.     

Low-Temperature Properties of Silver

Pure silver is used extensively in the preparation of high-temperature superconductor wires, tapes, films, and other configurations in which the silver not only shields the superconducting material from the surrounding materials, but also provides a degree of flexibility and strain relief, as well as stabilization and low-resistance electrical contact. Silver is relatively expensive, but at this stage of superconductor development, its unique combination of properties seems to offer the only reasonable means of achieving usable lengths of conductor. In this role, the low-temperature physical (electrical, thermal, magnetic, optical) and mechanical properties of the silver all become important. Here we present a collection of properties data extracted from the cryogenic literature and, to the extent possible, selected for reliability.     

Early ironwork in Biscay: Survey,excavation, experimentation and materials characterization. An integral study of the mountainside ironworks (ferrerías de monte or “haizeolak”)

ABSTRACT

The production of iron in Biscay (Basque Country, Spain) has been a hallmark of this territory of the North of the Iberian Peninsula throughout its history. The Archaeology team of the Basque Country Mining Museum has spent 13 years, so far, studying the origins of this activity through the evidences left at the old pre-hydraulic iron production workshops known as mountainside ironworks (ferrerías de monte) or haizeolak. It has catalogued 170 archaeometallurgical sites of this type in Biscay, and the archeological excavation of some of them has led to the knowledge of the different stages of the production process that took place in these workshops. The team has also experimentally reproduced the work carried out in a mountainside ironworks from the High Middle Ages, and it has currently started the characterization process of this type of activity through the study of the collected materials.     

Mechanism Study on the Wear of CrAlTiN Coated High-Speed Steel Twist Drills Under Dry Cutting Conditions

As demands about environment protection are growing up, dry cutting technology is getting more and more concerns from all over the world. Main works performed here are study on dry cutting performances and wear mechanisms of M2high-speed steel (HSS) twist drills with CrAlTiN multicomponent coatings, which was deposited using magnetron sputter ion plating system, in drilling 45 and 30CrMnSiA steel, and their comparisons to those in drilling the same steel but using monolayer CrN and commercial TiN coated drills. Drilling performances of drills are evaluated mainly through the measurements of width on outer corner flank land and the cutting forces. Results show that performances of CrAlTiN coated drills are better than those of monolayer CrN and TiN coated drills. In drilling 45 and 30CrMnSiA steel, the average tool life of the CrAlTiN coated drills are 17.2 and 11.8 times higher than those of the uncoated drills. Observing wear of the drill with scanning electronic microscope, results show that there is no crack or spallation of the CrAlTiN coatings in wear zones. Main mechanism of the wear here is adhesion.     

Study on Bond Ability of Arc-Spraying Coatings with Different Surface Pretreatment on Cast-Iron

Arc spraying coatings are widely used in various applications, but uncommon in cast iron substrate. Different surface pretreatment technology is tested on substrates of gray cast iron. Surface roughness and residual stress were measured by TR200 and X-ray diffraction analyzer. Influence of different surface pretreatment methods ( dry blasting and fusebond) on roughness and residual stress was analyzed. The arc-sprayed coatings of wire 3Cr13 (φ2mm) on gray cast iron substrate is studied. The microstructure and interface of bonding layer were observed by SEM. The bond strength was taken by tensile test. Results show that bond strength with grit blasting is higher than fuse-bond; it is feasible to make wire 3Cr13 coating with arc spraying on cast iron substrate roughened by grit blasting.     

Structural Characteristics of TiO2 Ceramic Coating by Micro-Plasma Oxidation

TiO2 ceramic coatings with thickness of 20 μm were formed on the surface of pure titanium by micro-plasma oxidation. Their micro-structures were investigated by by using X-ray diffraction and their surface images were detected by using scan electronic microscope. There were three kinds of TiO2 coatings, pure anatase type TiO2 phase, mixed phases consisted of rutile type TiO2 phase and anatase type TiO2 phase, pure rutile type TiO2 phase. The coating surface with the pure anatase type TiO2 phase is rough, while the coating surface with the pure rutile type TiO2phase is smooth. The upper coating surface with the mixed type TiO2 phases is anatase type TiO2 structure and the subsurface of the TiO2 coating is rutile type TiO2structure.     

Evaluation of fatigue life of steel using steel grain size

The insightful discussion of the relationship between the construction of metallographic and fatigue life and proposition of mathematical relationships describing this relationship was conducted in the paper. This paper presents a method for estimating the fatigue life, based on the construction of the microstructural material taking into account the grain size and the participation of ferrite and pearlite phase.