化工防腐用Ta40Nb合金板材加工工艺研究

用电子束熔炼得到Ta40Nb合金铸锭,研究了Ta40Nb合金的锻造和热处理工艺,结果表明,采用"轴向镦粗径向拔长+三向循环镦粗拔长"锻造工艺、"大加工率"的开坯轧制工艺,能更充分破碎Ta40Nb合金铸态组织,合金板材具有细小均匀的等轴晶。Ta40Nb合金板材成品处理采用1 200℃×90 min热处理工艺制度,能使材料最终获得均匀、细小的等轴晶组织,晶粒度达到8级以上。     

液钽电容器外壳用深冲EB钽带加工工艺研究

本文通过对锻造、轧制及热处理工艺的研究,测试了材料的力学性能、晶粒度及金相组织,确定最佳工艺为轴向镦粗径向拔长＋三向循环镦粗拔长的锻造工艺,换向轧制的开坯轧制工艺,950℃×90 min的热处理工艺,该工艺制备的材料符合性能要求。     

Ta5W合金板材高质化加工工艺研究

用电子束二次熔炼得到Ta5W合金铸锭,研究了Ta5W合金的锻造和热处理工艺。结果表明,采用"十字交叉镦拔"锻造工艺和大加工率"换向开坯"开坯轧制工艺,能更充分破碎Ta5W合金铸态组织,采用1 400℃×60 min热处理工艺,能使材料最终获得均匀、细小的等轴晶组织,晶粒度达到6.5级以上。     

内置前驱粉体真空自耗熔炼法制备ODS钢锭的组织演变

目的 探究内置前驱粉体真空自耗熔炼法制备ODS钢的可行性。方法 采用内置前驱粉体真空自耗熔炼法制备10 kg的ODS钢铸锭,对铸锭进行轧制及热处理,使用扫描电子显微镜和透射电子显微镜等手段研究铸锭组织特别是析出物的演变情况。结果 通过内置前驱粉体真空自耗熔炼法成功引入了过饱和氧化物粉体,热轧薄板中含有微米级的富Y氧化物和富Ti氧化物,且颗粒分布均匀,没有任何宏观或微观聚集现象。常规固溶热处理(1 200 ℃)和电流固溶热处理(1 000 ℃)均可减小热轧薄板中氧化物的尺寸,且经冷轧(压下量为80%)+1 000 ℃-10 min电流固溶热处理后,热轧薄板中的氧化物颗粒尺寸最小,富Ti和富Y的Y-Ti-O颗粒平均尺寸分别降至0.75 μm和0.17 μm。对薄板进行800 ℃-3 h的时效处理后,观察到纳米量级的Y-Ti-O复合氧化物析出,尺寸为20~200 nm。结论 内置前驱粉体真空自耗熔炼法成功将粉体引入铸锭中,轧制及热处理工艺能够显著细化氧化物颗粒并析出纳米量级的氧化物。     

氮化前显微组织对SmFeN合金磁性能的影响

本文研究了Sm含量,凝固速度及Nb和Zr元素的添加对Sm-Fe合金微观组织及氮化后Sm2Fei7Nx合金磁性能的影响.研究结果表明:采用真空感应炉熔炼Sm-Fe合金,当Sm的补偿量大于10wt%时,合金铸锭组织中出现大量的富Sm相,这将导致氮化后磁体磁性能的恶化;提高铸锭的冷却速度及添加Nb和Zr等元素可以有效地细化铸锭中α-Fe相的晶粒,减少均匀化退火后α-Fe相的数量,提高磁性能.     

变形热处理对Zr-1.0Nb合金耐腐蚀性能的影响

为了探究显微组织对Zr-1.0Nb合金耐腐蚀性能的影响,将Zr-1.0Nb合金样品分别进行680℃/500℃、680℃/560℃、800℃/500℃、800℃/560℃和1000℃/560℃五种变形热处理,然后在350℃、16.8 MPa、0.01mol.L-1的L iOH水溶液中腐蚀,并用透射电镜(TEM)研究其显微组织.其中800℃-1 h/冷轧/500℃-30 h处理样品的耐腐蚀性能最好,基体αZr中Nb元素固溶含量最低.通过变形热处理降低基体αZr中Nb元素固溶含量是提高Zr-1.0Nb合金耐腐蚀性能的一个关键因素.     

溅射镀膜用铌靶材晶粒尺寸控制工艺研究

铌靶材主要应用于表面工程材料,如船舶、化工、液晶显示器(LCD)以及耐热、耐腐蚀等镀膜行业。作为被溅射的基材,为了获得均匀一致的薄膜淀积速率,对溅射铌靶材的主要要求是均匀的组分、合适的颗粒尺寸以及具体的结晶学取向。本文主要研究在实际生产中,锻造工艺、轧制工艺以及热处理工艺对溅射镀膜用铌靶材晶粒尺寸的影响。通过多次试验,得到合理的锻造工艺、轧制工艺以及热处理工艺,从而对铸锭晶粒进行彻底的破碎和再结晶,最终得到晶粒尺寸小于100μm,且均匀一致的等轴晶组织,满足了溅射镀膜用铌靶材要求的晶粒尺寸和均匀等轴晶组织。     

超高纯银静态再结晶组织演变规律的研究

采用超高纯银(纯度高于99.999%)铸锭,通过轧制变形,结合后续不同热处理工艺,研究了变形量、退火温度及时间对超高纯银回复及再结晶组织的影响。结果表明:超高纯银的再结晶温度非常低,在100℃时保温5min后即发生再结晶,并且再结晶速度快,在200℃下保温5min即完成再结晶。随轧制总变形量增加晶粒尺寸变小,均匀性提高,当变形量大于等于85%时,可以得到均匀、细化的再结晶组织;超高纯银的最佳再结晶温度应控制在150℃,时间为1~2h之间。     

铸锭BFe30-1-1锻造性能的研究

研究了氧含量、夹杂物、宏观组织、拉制速度和电渣重熔等因素对BFe10 1 1合金铸锭锻造性能的影响,结果表明:氧含量、夹杂物对锻造性能影响不大,铸锭中的粗大晶粒及存在的缺陷将会降低锻造性能,而斜向生长的柱状晶区有利于锻造的质量控制,慢速停拉式铸造和合理的电渣重熔工艺对发挥合金的可锻性有利。     

电光源用Nb1Zr合金棒材加工工艺研究

研究了Nb1Zr合金棒材的新工艺制备技术,采用"挤压+径锻+型轧+涂层拉拔"替代原"自由锻+径锻+型轧+氧化拉拔+酸洗"工艺,有效保证了产品高精度尺寸公差要求,同时解决了原产品工艺酸洗造成的环保问题。Nb1Zr合金棒材成品处理采用1 350℃/60 min真空退火工艺,材料最终晶粒度≥7级。研究了棒材变形工艺、退火温度、保温时间等因素对Nb1Zr合金棒材再结晶晶粒大小的影响。     

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.