薄壁铸铁件湿型铸造涂料的实验与应用

本文介绍铸铁湿型铸造中的型腔表面使用的喷涂涂料,该涂料可有效的防止粘砂、掉砂、冲砂等铸造缺陷。铸件表面质量明显提高。     

SO2 abatement,energy conservation,and productivity at copper cliff

Inco pioneered the use of tonnage oxygen in nonferrous metallurgy when it commissioned the first industrial oxygen flash smelting process for the treatment of copper concentrates in the early 1950s. This was followed by other applications of oxygen such as the enrichment of reverberatory furnace and Peirce-Smith converter blasts; oxy-fuel smelting in reverb furnaces; and, very recently, flash conversion of chalcocite to copper. Inco is currently implementing a sulfur dioxide abatement project designed to reduce SO₂ emissions from the smelter by 60 percent (to 265 kt) in 1994. At that time, oxygen consumption at the smelter will reach about 1.7 t O₂/t Cu+Ni. Oxygen smelting and converting technology will lead toa substantial decrease in the use of fossil fuels and to the generation afhigh-strength SO₂ off-gases suitable for cost-effective fixation in a new acid plant.     

玻璃熔炉烟气脱硫、除尘、脱硝技术开发

简介彩电玻壳生产线锥炉、屏炉烟气脱硫、除尘、脱硝设备技术开发.投产应用表明,整套技术可在玻壳行业及其它类似行业推广应用.     

涂料技术的发展、配方及种类

本文包含了涂料的发展。它显示了涂料制造厂商是怎样开发新配方以满足新环境条件和规则所带来的日益增长的要求。本文讨论了常用的涂料，介绍了涂料领域的技术、服务的基本理解和认识。     

热喷锌、冷喷锌与富锌涂料三种涂层的耐蚀性对比

通过厚度测量、腐蚀电位测试和盐雾试验对钢铁结构腐蚀防护中常用的热喷锌、冷喷锌和富锌涂料三种涂层的耐蚀性进行了对比研究。结果表明:热喷锌涂层厚度不均匀,致密性差,盐雾试验21d后,涂层以点蚀的形式失效;富锌涂料涂层的腐蚀电位高于另外两种涂层的,在湿热盐雾环境中,鼓泡导致涂层和基体脱离而失去保护作用;冷喷锌涂层的厚度均匀,与基体结合力强,具有自修复能力和最好的耐蚀性。     

节能、降耗、减排是硅热法炼镁发展的生命力

为使硅热法炼镁达到节能、降耗、减排的目的,介绍了白云石、硅铁的质与量,煅白中CaO的水化活性度、炉料的物理性质、球团真空还原时供热与传热速度、镁蒸气的生成与扩散速度的能量与质量的动态平衡条件以及提升装备水平和设备大型化等方面的技术要求。     

Validation of a systematic approach to modeling spray quenching of aluminum alloy extrusions, composites, and continuous castings

Optimal cooling of aluminum alloys following the high- temperature extrusion process suppresses precipitation of intermetallic compounds and results in a part capable of possessing maximum strength and hardness after the subsequent age- hardening process. Rapid quenching suppresses precipitation but can lead to large spatial temperature gradients in complex- shaped parts, causing distortion, cracking, high residual stress, and/or nonuniform mechanical properties. Conversely, slow cooling significantly reduces or eliminates these undesirable conditions but allows considerable precipitation, resulting in low strength, soft spots, and/or low corrosion resistance. This study presents a systematic method of locating and operating multiple spray nozzles for any shaped extrusion such that uniform, rapid cooling and superior mechanical and metallurgical properties are achieved. A spray nozzle data base was compiled by measuring the distribution of spray hydrodynamic parameters (volumetric spray flux, mean drop diameter, and mean drop velocity) throughout the spray field of various industrial nozzles. Spray heat transfer correlations, which link the local spray hydrodynamic parameters to the heat transfer rate in each of the boiling regimes experienced by the surface, defined the spatially nonuniform boundary conditions in a numerical model of the quenching process that also accounted for interference between adjacent spray fields. New correlations, offering increased accuracy and less computational time, were formulated for the high- temperature boiling regimes which have a critical influence on final mechanical properties. The quench factor technique related predicted thermal history to metallurgical transformations occurring within the extrusion to predict hardness distribution. The validity of this unique approach was demonstrated by comparing model predictions to the temperature response (and hardness after artificial aging) of an L- shaped Al 2024- T6 extrusion to quenches with multiple, overlapping water sprays. The validation study reported herein concludes by exploring the possibility of applying quenching technology to improving the properties of extruded metal- matrix composites such as SiC_p/Al 6061 and cast alloys.     

输送流体管道的沥青防腐层寿命、破坏原因及其危害

本文重点分析了影响沥青防腐层寿命与破坏的影响因素，局部破损的巨大危害及其避免方法，检查的方法，强调了管道的回填必须按照有关规范要求严格执行及其道理。     

多孔氧化铈空心微球的合成、表征及其脱色性能

以聚苯乙烯微球为模板、六水硝酸亚铈为铈源、六亚甲基四胺为沉淀剂,制备不同壳厚的氧化铈空心微球;利用XRD、TEM、FESEM、XPS和氮气吸附一脱附等手段,对所制备样品的微观结构进行表征.将所制备的Ce02空心微球用于甲基橙模拟染料废水的脱色处理.结果表明:CeO2空心微球具有多孔结构,表面平均孔径约为10 nm,球径约为200～250 nm,壳厚约为10～30 nm,壳层是由粒径为5～10 nm的CeO2颗粒所组成;甲基橙溶液经CeO2空心微球处理60 min后,其脱色率可达95%以上,表现出良好的脱色性能.     

物理气相沉积(Ti,Al)N涂层刀具的切削性能

涂层已成为提高刀具切削性能的重要手段。对上海工具厂镀膜机制备的（Ti,Al）N涂层性能分析发现,其表面硬度达到32GPa,高于TiN的24GPa;同时,涂层表面生长良好。在试验室进行的干式切削试验表明,（Ti,Al）N涂层切削过程中磨损小于TiN涂层,切削寿命高于TN涂层;（Ti,Al）N涂层适合高速切削,分析了（Ti,Al）N涂层适合高速切削的主要原因。     

化学镀锡层成分与表面形貌及结构分析

借助于扫描电子显微镜和X-射线衍射仪,研究了不同工艺条件下化学镀锡层的成分、表面形貌及组织结构,同时对测试结果做分析.结果表明:(1)通过控制沉积时间,可获得锡的质量分数为92%～97%半光亮银白色的锡镀层,此外镀层中还含有少量的Cu及微量的Fe、N、C、S、O等元素.(2) 时间越长、温度越高,沉积的晶粒粒度越大.添加剂B和添加剂C有明显的细化晶粒作用.(3) 沉积时间延长,镀层中β-Sn相的峰值增强,Cu相峰值减弱,表明镀层在不断增厚.     

空心阴极离子镀(Ti,Zr)N膜层制备及应用研究

用空心阴极离子镀(HCD)技术制备了(Ti,Zr)N膜层,研究了氮分压对膜层硬度的影响.以结合强度为判据,采用基体温度、轰击气压、负偏压及中间层沉积时间作为试验的变化因素,用正交试验法优化了制备(Ti,Zr)N膜层的最佳工艺规范.应用优化的工艺参数对印制板(PCB)刀具进行了镀膜强化应用,结果表明,镀层性能良好,能够延长刀具的使用寿命.     

Morphology,Structure, Microhardness and Corrosion Resistance of Ni-W Coating Annealed in Hydrogen and Argon Atmosphere

In this paper, an amorphous Ni-W coating was electrodeposited on the low-carbon steel and then annealed in hydrogen and argon atmosphere. Their characterization was carried out using scanning electron microscopy and x-ray diffraction. The corrosion characterization was carried out using the potentiodynamic polarization (Tafel) and electrochemical impedance spectroscopy. The results show that microcracks inevitably exist on the surface of Ni-W coating when annealed at 750 °C or higher temperature. After annealing treatment, amorphous structure transforms to crystalline and some new phases are precipitated, which is significantly affected by the annealing temperature and atmosphere. The microhardness of annealed Ni-W coatings is much higher than that of as-deposited coating, while an adverse corrosion performance is observed for the annealed Ni-W coatings. The coating annealed in hydrogen at 500 °C shows a huge improvement in hardness and a fairly acceptable corrosion resistance compared with the as-deposited Ni-W coating.     

Comparison of In-Flight Particle Properties, Splat Formation, and Coating Microstructure for Regular and Nano-YSZ Powders

The relationship between atmospheric pressure plasma spray parameters and in-flight particle characteristics was determined. The morphologies of individual splats and the coating microstructure were studied for different stand-off distances and arc currents. Coating cross-sectional analysis showed that the total porosity of the coating increased with decreasing arc current, and increasing stand-off distance. Two different materials were used: the regular (r-YSZ) feed stock and the nano size (n-YSZ) agglomerated powder. The results illustrate that the r-YSZ coating has higher total porosity at higher arc currents than n-YSZ coating. The splat flattening degree and circularity was examined at different substrate temperatures for both powders. The results indicate that the flattening degree increased at high temperatures for the two materials, but the values for n-YSZ were higher than those for the r-YSZ. This study showed the operating regimes in which the use of n-YSZ yields improved coating properties.