微波场作用下非晶合金Fe73.5Cu1Nb3Si13.5B9的纳米晶化

研究了微波场对晶化的影响.结果表明,将非晶合金Fe73.5Cu1Nb3Si13 5B9在微波场作用下在480℃短时间(5 min)晶化处理,形成体积分数为80%、尺寸约15nm的α-Fe(Si)相;适当延长晶化时间(30 min)使非晶合金完全晶化,α-Fe(Si)相的晶粒不再长大,原子层之间的距离降低至0.2461 nm,磁体具有最大Ms为1.79 T.与激光、激波、脉冲电场和脉冲磁场晶化处理相比,微波场晶化处理可同时获得单一的、更小晶粒尺寸和更高体积分数的α-Fe(Si)晶化相,使合金具有高的饱和磁化强度和优良的软磁性能.微波场有利于非晶合金中的硼原子向空位跃迁,使基体金属相α-Fe(Si)相的形核率增大,促进非晶合金的纳米晶化.     

预退火对Sm5 Fe74.3Nb1.5Si11.7 B4.5C2.5Cu0.5非晶合金晶化动力学的影响

研究了预退火对Sm5Fe74.3Nb1.5Si11.7B4.5C2.5Cu0.5非晶合金晶化动力学的影响。结果表明，预退火处理使非晶合金晶化相α-Fe和Sm2Fe17Cx的晶化温度（Tp）和晶化表观激活能（Ec）值降低，且改变晶化相α-Fe在晶化过程中晶化激活能的变化趋势，有助于该合金在晶化退火中形成晶粒尺寸较小的α-Fe相。     

Fe74Al4Ga2P12B4Si4块体非晶合金的纳米晶化及软磁性能研究

采用铜模铸造法制备了厚2mm的Fe74Al4Ga2P12B4Si4块体非晶合金.利用X射线衍射(XRD)、差热分析(DSC)和振动样品磁强计(VSM)研究了其晶化行为和软磁性能.结果表明,非晶合金的玻璃转变温度Tg为457.35℃,晶化开始温度Tx为497.65℃.合金的过冷液相区宽度△Tx达到40.30℃,表明合金具有较大的玻璃形成能力.F74Al4Ga2P12B4Si4合金的晶化是二级晶化过程.经520℃等温退火后析出α-Fe相,其晶粒尺寸为15.9nm;而经550℃等温退火后析出α-Fe相及微量的A10.3Si0.7Fe3和Fe3B相,其中α-Fe相的晶粒尺寸为17.4nm.非晶合金的饱和磁化强度为108.816emu/g、矫顽力Hc为574.97Oe;经520℃等温退火后,纳米晶合金的饱和磁化强度为106.875emu/g、矫顽力Hc为94.16Oe.退火实验结果表明,纳米晶化对材料的饱和磁化强度没有显著影响,但会显著降低材料的矫顽力.     

FeCoNbSiBCu大块非晶合金的热稳定性与晶化过程研究

用差示扫描量热分析和原位高温X射线衍射研究了(Fe36Co36Nb4Si4.8B19.2)100-xCux(x=0, 0.5, 0.6, 0.7)大块非晶合金的热稳定性及其晶化过程.结果表明,微量Cu显著改变了Fe36Co36Nb4Si4.8B19.2大块非晶合金的晶化过程,无铜合金表现出单一尖锐晶化峰,而含铜量原子分数为0.5%,0.6%和0.7%的晶化过程分为四个阶段,Cu的加入提高了非晶合金纳米析出相的热稳定性.原位X射线衍射研究表明,FeCoNbSiBCu大块非晶合金初始晶化相为bcc-FeCo并于930K转变为bcc-Co7Fe3相.Cu添加后bcc-Co7Fe3的晶化表观激活能由460.41kJ/mol升高至545.69kJ/mol.用谢乐公式计算样品在840K保温17.5min的平均晶粒尺寸为22.3nm.     

Fe77Co2Zr9B10Cu2合金的制备及其磁性能

采用单辊快淬法制备了Fe77Co2Zr9B10Cu2合金,在530～750℃等温退火40 min,利用X射线衍射和振动样品磁强计研究了Fe77 Co2 Zr9 B10 Cu2合金的微观结构和磁性能。结果表明:淬态Fe77Co2Zr9B10Cu2合金为非晶、纳米晶双相结构。随着退火温度的升高,α-Fe晶体相从非晶、基体中析出,晶粒尺寸长大,晶化体积分数增加,矫顽力先减小后增大,比饱和磁化强度逐渐增大。实验结果表明,530℃退火后合金的矫顽力最小,在670℃时迅速增大。样品的磁性与其微观结构、晶粒尺寸、晶化体积分数等因素有关.     

非晶Sm5Fe74.3Nb1.5Si11.7B4.5C2.5Cu0.5合金经预退火后的晶化动力学的DTA研究

研究了非晶Sm5Fe74.3Nb1.5Si11.7B4.5C2.5Cu0.5合金经400℃，保温10min预退火后的晶化动力学。结果表明；该合金的晶化相为α-Fe固溶体和Sm2Fe17Cx金属间化合物，两相的晶化表观激活能分别为557KJ/mol和514KJ/mol，当晶化体积分数为60%时，α-Fe相的晶化激活能达极大值；Sm2Fe17Cx相晶化激活能则随其晶化体积分数的增加而逐渐减小。     

热处理对(Fe_(0.52)Co_(0.30)Ni_(0.18))_(73)Cr_(17)Zr_(10)非晶合金的组织结构及磁性能的影响

采用单辊急冷法制备(Fe_(0.52)Co_(0.30)Ni_(0.18))_(73)Cr_(17)Zr_(10)非晶薄带,并对该合金进行等温退火。采用XRD,AFM,VSM研究退火温度对(Fe_(0.52)Co_(0.30)Ni_(0.18))_(73)Cr_(17)Zr_(10)非晶合金的组织结构和磁性能的影响。结果表明:非晶合金晶化过程为Am→α-Fe(Co)+Am′→α-Fe(Co)+Cr_2Ni_3+Fe_3Ni_2+Cr_2Zr+未知相。当退火温度Ti玻璃转变温度Tg时,由于结构弛豫、内应力的释放,合金的饱和磁化强度Ms有所提高;当晶化起始温度TxTi第一晶化峰值温度Tp1时,由于铁磁性α-Fe(Co)相的析出,Ms显著提升;当TiTp1时,由于晶粒长大和第二相的析出,Ms急剧恶化,565℃退火能够获得最好磁性能(Ms=106.8A·m~2·kg~(-1))。490℃和565℃退火后薄带表面的AFM观察表明,AFM图片所呈现的颗粒尺寸要比用Scherrer法测得的α-Fe(Co)纳米晶尺寸大得多,这是典型的包裹晶粒现象。     

Nd2Fe14B/(α-Fe,Fe3B)复合纳米晶的生长动力学研究

采用X射线衍射分析(XRD)研究了Fe-Co-Nd-Dy-B非晶合金晶化过程中α-Fe、Fe3B纳米晶的生长动力学.根据纳米晶生长达到稳定状态所需的时间常数tE与退火温度Ta的关系,计算了α-Fe和Fe3B纳米晶的生长激活能为Egα-Fe=95±2 kJ/mol和E Fe3B=133±13 kJ/mol.该值远小于α-Fe和Fe3B两相的表观晶化激活能Ecα-Fe=555 kJ/mol和EcFe3B=481 kJ/mol.这表明Fe-Co-Nd-Dy-B非晶合金晶化过程中α-Fe和Fe3B纳米晶的形成主要由成核所控制.     

Zr对Pr-Fe-B非晶合金晶化形成纳米晶合金的作用

从非晶合金化激活能的角度，分析了Pr-Fe-B非晶合金在退火过程中晶粒粗大的原因，揭示了Zr元素在其晶化过程中的作用，结果表明，Zr能改变Pr-Fe-B非晶合金中α－Fe相的晶化行为，有助于形成尺寸细小的α-Fe相。     

添加Nb对Fe74Al4Ga2P12B4Si4非晶合金晶化过程的影响

利用X射线衍射(XRD)、差热分析(DSC)和扫描电镜(SEM)方法试验研究了Nb元素对Fe-(Al,Ga)-(P,C,Si,B)系合金非晶晶化的影响.结果表明:Fe73Nb1Al4Ga2P12B4Si4的晶化过程为α-Fe→α-Fe Fe5SiP Al0.7Fe3Si0.3 Fe3B 剩余非晶化相;替代元素Nb的加入提高了材料的晶化温度,改变了Fe74Al4Ga2P12B4Si4的晶化激活能,其中形核激活能(Eg)、晶化起始激活能(Ex)和第一晶化峰激活能(Ep1)都大大增加;另外,Nb的加入显著降低了合金晶化后的晶粒尺寸,并改善了晶粒的均匀度.     

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 Institutions Expected to Update and Transfer Information on Present Standards

Standards are the basis for production enterprises to organize production, ex-factory inspection, trade (delivery) and technical exchanges, product certification, quality arbitration and supervision.……     

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.     

Optimum-Simulation von Ernteprozessen

Zusammenfassung Bei der Gestaltung von Ernteprozessen — beispielsweise des Prozesses Mähdrusch, Körnertransport und -abnahme — als transportverbundene Fließarbeitsverfahren mit mindestens zwei verschiedenen Arbeitsmitteln gibt es einen großen Optimierungsspielraum. Solche Prozesse sind mehrstufige Bedienungsprozesse mit gemischter Anordnung der Bedienungseinrichtungen. Außerdem besitzen sie stark ausgeprägte räumliche Aspekte. Es wird vor allem gezeigt, welche Merkmale solcher Prozesse in Simulationsmodellen abgebildet sein müssen, welche Zielgrößen in Abhängigkeit von welchen Einflußgrößen unter Berücksichtigung welcher Prozeßbedingungen ermittelt werden sollten und wie der Bewertungsprozeß zur Ermittlung der gewünschten Informationen gestaltet werden muß.     

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.     

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.