化学镀Ni—P—PTFE复合镀层的性能

本文对化学镀Ｎｉ－Ｐ－ＰＴＦＥ复合镀层的性能作了测定和评价。实验表明，用优化的镀液配方加工艺可获得含ＰＴＦＥ粒了２５－３０％ｖｏｌ的Ｎｉ－Ｐ－ＰＴＦＥ复合镀层。这种镀层具有优良的结合力和良好地耐蚀性，其硬度随ＰＴＦＥ含量增加而降低，其特别突出的性能是优异的减性和耐磨性，是一种具有自润滑功能的表面复合材料。     

Ni—P—PTFE复合镀层应用研究

将用正交试验法获得的Ｎｉ－Ｐ－ＰＴＦＥ施镀工艺应用于气体轴承中，探索其在气体轴承中应用的可行性。结果表明，Ｎｉ－ＰＴＦＥ复合镀层可使气体轴承的摩擦学性能明显提高。     

化学镀Ni—P—PTFE复合镀层沉积工艺研究

对化学镀Ｎｉ－Ｐ－ＰＴＦＥ复合镀层工艺进行了较全面的研究。详细测定和评述了表面活性剂浓度，ＰＴＦＥ浓度与镀层中ＰＴＦＥ粒子含量及镀速的关系，以及基础镀液性质和操作条件对复合镀的影响。提出了一种具有实用价值的化学镀Ｎｉ－Ｐ－ＰＴＦＥ复合镀层工艺技术。镀液稳定，镀层质量优良，镀层中ＰＴＦＥ含量达２５￣３０ｖｏｌ％。     

复合镀层的沉积规律和憎液性

研究了在Ｎｉ－Ｐ－ＰＴＦＥ化学复合液中，阳离子表面活性剂的种类含量，镀液中ＰＴＦＥ含量，镀液老化时间等对镀层中ＰＴＦＥ沉积状态的影响，给出了合理的解释，考察了该镀层的憎液性。     

电沉积RE-Ni-W-P-SiC-PTFE复合材料的耐磨性研究

采用多元复合电沉积技术,沉积含有弥散硬质相及自润滑减摩组分ＰＴＦＥ的复合镀层,研究了热处理条件对ＲＥ－Ｎｉ－Ｗ－Ｐ－ＳｉＣ－ＰＴＦＥ复合镀层的硬度及磨损率的影响。确定４００　℃,２　ｈ的热处理条件能使复合镀层具有最佳摩擦学特性：硬度最高,磨损率最低。试验发现,复合镀层中添加ＰＴＦＥ,会使镀层的硬度有所降低,但却能显著降低磨损率,大大提高镀层的耐磨性。     

国内期刊纵览

20 0 0 0 80 1　电沉积ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ———郭忠诚 .电镀与涂饰 (双月刊 ) ,2 0 0 0 ,19( 3 ) :1研究了ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ复合镀层的性能。结果表明 ,热处理温度对ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ复合镀层的硬度影响很大 ,当温度达到 40 0℃时 ,复合镀层的硬度达到极大值 ( 114 5ＨＶ) ;在同一热处理温度下 ,当保温时间达到 3ｈ ,镀层的硬度值最佳。当热处理温度达到 3 0 0℃时 ,ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ复合镀层的耐磨性最好。高温氧化试验表明 ,ＲＥ Ｎｉ Ｗ Ｐ Ｂ4 Ｃ ＰＴＦＥ复合镀层随氧化…     

Ni－P－PTFE复合镀层应用研究

将用正交试验法获得的Ｎｉ－Ｐ－ＰＴＦＥ施镀工艺应用于气体轴承中，探索其在气体轴承中应用的可行性。结果表明，Ｎｉ－Ｐ－ＰＴＦＥ复合镀层可使气体轴承的摩擦学性能明显提高。     

基体表面状况、表面活性剂浓度对Ni-P-PTFE化学镀层结构的影响

采用扫描电子显微镜研究了被镀基体表面的粗糙状况和表面活性剂浓度对Ｎｉ－Ｐ－ＰＴＦＥ化学复合镀镀层微结构的影响。前者的影响是：基体表面的道痕不能被复合镀层所填满,在通常情况下镀层的表面形貌会基本上保持基体的表面状况。但当基体表面过度粗糙,尤其是当道痕又细又密时,会使整个镀层比较疏松并出现较多的空洞。后者的影响是：在表面活性剂浓度过低时所沉积的镀层中只含有很少量的ＰＴＦＥ粒子,在其浓度过高时所沉积的镀     

化学镀Ni－P－B_4C复合镀层的耐磨性

本文通过比较化学镀Ｎｉ－Ｐ－Ｂ＿４Ｃ复合镀层、Ｎｉ－Ｐ－ＳｉＣ复合镀层、Ｎｉ－Ｐ合金层和电镀铬层的性能，发现Ｎｉ－Ｐ－Ｂ＿４Ｃ复合镀层是其中最理想的抗磨材料。试验证明：由于Ｂ＿４Ｃ微粒的硬度高于ＳｉＣ微粒，并且Ｂ＿４Ｃ本身又具有较高的抗显微切削能力，所以Ｎｉ－Ｐ－Ｂ＿４Ｃ复合镀层的耐磨性显著高于Ｎｉ－Ｐ－ＳｉＣ复合镀层和Ｎｉ－Ｐ合金层。由于电镀硬铬层的硬度随磨擦热的升高而迅速下降，所以其耐磨性远不及Ｎｉ－ＰＢ＿４Ｃ复合镀层。     

电沉积ＲＥ—Ｎi—W—P—SiC—PTFE复合材料的耐磨性研究

采用多元复合电沉积技术，沉积含有弥散硬质及自润滑减摩组分ＰＴＦＥ的复合镀层，研究了热处理条件对ＲＥ－Ｎi-P-SiC-PTFE复合镀层的硬度及磨损损率的影响，确定４００℃，２h的热处理条件能使复合镀层具有最佳磨擦学特性，硬度最高，磨损率最低，试验发现，复合支中添另ＰＴＦＥ，会使镀层的硬度有所降低，但却能显著降低磨损率，大大提高镀层的耐磨性。     

From Industry 4.0 to Research 4.0. Development of High Performance Fibers in the Light of Digitization

We associate a variety of innovations with the term ＂Industry 4.0＂. The pioneer of many 4.0 modifications forms the basisfor the trend towards the integrated di...     

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.     

Roman iron and steel: A review

ABSTRACT

The production of ferrous metal increased during the Roman Late Republican period, Principate and Empire. The direct bloomery process was used to extract the metal from its ores using slag-tapping and slag-pit furnaces. The fuel was charcoal and an air blast was introduced by bellows-operated tuyères. Iron formed as a bloom, often as a spongy mass of metal, which contained impurities from the smelting process, including unreacted ore, fuel, slag and fragments from the furnace walls, while the metal was often inhomogeneous with varied carbon contents. Blooms were either smithed directly into bars or ingots or they were broken up, which also allowed the removal of gross impurities and a selection of pieces with similar properties to be made. These could then be forge-welded together and formed into characteristically shaped ingots. Making steel in the furnace seems to have been achieved: it depended on the ore and the furnace and conditions within it. Surface carburization was also carried out. Iron and steel were used extensively in construction and for tools and weapons. Fire welding was often used to add pieces of steel to make the edges of tools and weapons, which could be heat-treated by quenching to harden them.     

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.……     

Synthesis of Alumina-Zirconia Nanocomposites by Solgel Process

Al₂O₃-ZrO₂ nanocomposites were developed starting with the solgel process. Composite alumina-zirconia nanopowders were synthesized from metallorganic precursors (Aluminium secondary butoxide and zirconium Iso propoxide) using the solgel process. The parameters affecting the synthesis—solvent, concentration of precursor, R/H ratio (i.e., dilution of water in solvent)—were varied as also the temperature and pH. BET and TEM were used to measure nanosize. Diffuse reflectance spectroscopy and also qualitative optical absorption led to identical particle size estimate. The variation of process parameters was used to study the effect and interdependence of process parameters. Artificial Neural Networks was used to rigorously analyze the process. Although this led to confirmation of interdependence of parameters, the presence of a single overwhelming solvent variable was also established. Then the optimal process was used to synthesize more nanopowder. To produce bulk nanocomposite the nanopowders were sintered by varying the temperature and time period. The sintered lithoids were probed with a vickers hardness tester to measure elastic modulus, hardness, and fracture toughness. The results showed high elastic modulus, modest hardness, and very high fracture toughness.     

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.