Al—P中间合金对Al—Si合金的“绿色”变质

用 Al- 3P中间合金对 ZL1 0 9合金进行了变质生产试验 ,研究了其在生产中的工艺参数及加入工艺。对共晶成分的 Al- Si合金 ,其加入量按 W原料 × ( 0 .4%～ 0 .45 % ) + W回炉料 × 0 .1 %=WAl-3 P中间合金 进行计算称量 ,在 760～ 770℃变质即可取得良好的变质效果 ,生产出品质优良的活塞铸件。使用 Al- P中间合金变质剂加入方便 ,无渣无污染 ,可以提高合金的实收率、降低生产综合成本 ,适于工业化生产应用 ,是磷盐变质剂良好的替代品。     

TiC对新型Al-P中间合金变质效果的促进作用

本文研究了自制新型Al-P中间合金对共晶及过共晶Al-Si的变质作用。发现该Al-P中间合金对共晶及过共晶Al-Si合金都具有优良的变质效果。同时还发现，当铝合金熔体中存在TiC颗粒时，Al-P中间合金对两类Al-Si合金的变质效果会增强。当Al-24Si合金中TiC含量为0.03%时，初晶Si的平均尺寸由原来的47μm降为41μm，最大尺寸由原来的75μm降为55μm；加入Al-P中间合金和TiC颗粒后50分钟，就可以出现变质效果，时间再延长，变质效果也不会有更大的提高，当Al-12Si合金中TiC含量为0.03%时，初晶Si的平均尺寸幅度原来的50μm降为30μm,Al-P中间合金变质剂在铝合金活塞中有较好的应用。     

过共晶Al-Si合金的双重变质处理

过共晶AI-18％Si合金中加入适当比例的AI-3．5％P中间合金、AI-10％RE以及AI-8％Ba进行变质处理，能同时细化初晶Si和共晶Si，在加入变质剂90分钟时，初晶硅颗粒数量多，分布均匀，而且尺寸细小，共晶Si由片状变为珊瑚状，热处理后，初晶Si更加圆滑，共晶Si呈点状分布，达到了良好的双重变质效果。     

过共晶Al—Si合金的P—S双重变质

研究了Ｐ－Ｓ双重变质处理对一种过共晶Ａｌ－Ｓｉ合金显微组织和性能的 时确定了双重变质剂的最佳加入量。结果表明：Ｐ－Ｓ双重变质比Ｐ单一变质更好。     

Al-P中间合金的变质特性及变质机理探讨

通过在众多活塞厂家应用表明：A1-P中间合金无污染、无反应渣，变质效果好且稳定；节约能源，降低铝耗，综合成本低，克服了当前变质的缺点，有着广阔的应用前景。本文还探讨了A1-P中间合金的变质机理。     

铝硅活塞合金的组织细化浅析

1　前言为了提高铝活塞的高温机械性能 ,必须对共晶及过共晶的铝硅合金进行变质处理。目前 ,我国许多活塞厂家都已采用磷来细化初晶硅即可获得热膨胀系数低、尺寸稳定性高、导热性、耐磨性高抗腐蚀性好的优质活塞。现对目前活塞厂家通常采用的几种变质方法进行比较。2　几种变质方法优劣的比较对共晶组织有变质作用的元素有 Na、Ca、Ba、K、Sr、Sb、Te、Ti、Li以及稀土元素等。目前用于生产实际的变质元素有 Na、Sb和 Sr,对过共晶组织有变质作用的元素有 P、As和 S。1　Na变质处理钠是共晶类铝硅合金最常用的变质剂。钠的变质效果直…     

Al-Si-P中间合金对过共晶Al-Si活塞合金的高效细化处理

研究了Al-11Si-4.5P中间合金对过共晶Al-18Si合金的细化处理,并将其磷吸收量与Cu-8P中间合金和磷盐进行了比较。结果表明,Al-11Si-4.5P中间合金对过共晶Al-18Si合金具有显著细化效果。此外,发现在相同细化条件下,Al-11Si-4.5P中间合金的磷吸收量要远远高于其他含磷细化剂。该中间合金具有细化效果好、长效、无污染、使用简便和使用成本低等优点,具有广阔的应用前景。     

红梅-3号特种合金磷变质剂的研制与应用

为满足铝活塞产品质量的需要，继“红梅—1号多功能磷复合变质剂”和“红梅—2号磷酸盐块状变质剂”后，我们又新研制开发了多相长故、环保型“红梅—3号特种合金磷变质剂”。这是一种高技术合量的新型以—Si合金磷变质剂，无论在产品质量上、使用性能上还是变质效果可与国外生产的P——Cu棒变质剂媲美。     

新型Al-P中间合金对活塞合金中初晶Si的团球化

研制出一种新型 Al- P中间合金 ,结果表明 :该中间合金不仅具有无污染、无渣、操作简便和变质效果稳定等优点 ;而且合理地使用该中间合金时 ,可使初晶 Si晶粒得到团球化 ,提高活塞的金相等级 ,提高质量 ,降低废品率 ,有着广阔的应用前景。     

铝——硅共晶活塞合金的Na,P变质

本论文致力于KS1275活塞合金分别经Na,P变质后，在机械，物理性能以及铸造性能等方面的比较，同时基于铸造理论和实践结果，对影响P变质效果的一些重要因素进行分析，小结。     

Uniform Cooling of Alloys

A phase separation process model formed by the Cahn– Hilliard equation and the heat equation is considered. The mobility coefficient in the Cahn–Hilliard equation is assumed to be an increasing function of the temperature. This property is of importance at the latest stage of the cooling process. The existence and uniqueness of a weak solution is proved, and a uniform cooling problem is studied. Obtained results can be used to control the cooling process and to create alloys with a uniform structure. 2000 Mathematics Subject Classification. 35K30, 35Q99, 49J20.     

铸造锌合金的研究进展与实际应用

叙述了锌合金的基本分类和特点,以及其中各个元素的作用,指出了铸造锌合金过程中要注意的问题,探讨了锌合金的发展。     

合金铸铁气缸套铸造工艺

气缸套作为发动机核心部件之一，其性能直接影响着整机的大修周期与功效稳定，因此需要气缸套采用性能好、品质优良的合金铸铁，本文分别从合金铸铁铸造的各道工序进行分析，提出影响材质性能的因素，为提高合金铸铁气缸套性能提供研讨。     

高温材料在燃气轮机中的应用和发展

高温合金材料是燃气轮机材料中极其重要的组成部分。在燃气轮机燃烧室、导向叶片、涡轮动叶片以及涡轮盘等部位上都有着极其广泛的应用。本文就当前燃气轮机所采用高温合金的主要特点及新技术的应用情况进行了分析和说明,并对目前世界主要国家的研制水平和发展趋势进行了深入的介绍。     

Computational Modeling of GMAW Process for Joining Dissimilar Aluminum Alloys

A three-dimensional transient model is developed to solve for heat transfer, fluid flow, and species distribution during a continuous gas metal arc welding (GMAW) process for joining dissimilar aluminum alloys. The phase-change process during melting and solidification is modeled using a fixed-grid enthalpy-porositytechnique, and Scheil's model is used to determine coupling among composition, temperature, and the liquid fraction. The effect of molten droplet addition to the weld pool is simulated using a “cavity” model, in which the droplet heat and species addition to the molten pool are considered as volumetric heat and species sources, respectively, distributed in an imaginary cylindrical cavity within the molten pool. To establish the model for joining dissimilar alloys, results for joining two pieces of a similar alloy are also presented. The dissimilar welding model is demonstrated using a case study in which a plate of wrought aluminum alloy (with approximately 0.5 wt% Si) is butt-welded to an aluminum cast alloy plate (with approximately 10 wt% Si) of equal thickness using a GMAW process. Macrosegregation, along with the associated heat transfer and fluid flow phenomena and their role in the weld pool development, are discussed. The model is able to capture some of the key features of the process, such as differential heating of the two alloys, asymmetric weld pool development, mixing of the molten alloys, and the final composition after solidification.     

Temperature Determination Using Multispectral Radiation Thermometry Algorithms for Aluminum Alloys

Multispectral radiation thermometry (MRT) was applied to predict the aluminum surface temperature. Experiments were conducted to measure the spectral intensity values for five different aluminum alloys, AL1100, AL2024, AL5083, AL6061, and AL7005, at 600 K, 700 K, and 800 K. The experimental work is coupled with six MRT emissivity models encompassing mathematical and analytical functions to infer surface temperature. Assessment of the MRT emissivity model is subject to parametric effects of number of wavelengths, alloy composition, and temperature. Results show that increasing wavelength number does not significantly improve measurement accuracy while applying MRT. If the emissivity model can represent well the real emissivity behaviors, a more accurate inferred temperature can be achieved. Overall, most models achieve high accuracy in temperature prediction, except two emissivity models. One particular emissivity model provides the best compensation for the aforementioned parametric influences.     

Alloys and oxides on carbon-supported Pt-Sn electrocatalysts for ethanol oxidation

This work reports studies of ethanol oxidation on Pt-Sn/C catalysts with nearly the same particle size and identical overall composition having different amounts of oxide and alloyed phases. Results of characterization of physical properties by transmission electron microscopy (TEM), X-ray diffraction (XRD), differential scanning calorimetry (DSC), X-ray photoelectron spectroscopy (XPS), and in situ dispersive X-ray absorption spectroscopy (DXAS) are presented. The variation in the amount of oxide and alloyed phases, promoted by heat treatments in mild temperature conditions, does not produce any significant particle growth. Cyclic voltammetry and oxidation of adsorbed CO in acid medium are used to probe the surface conditions. Data on the electrocatalytic activity towards ethanol oxidation, obtained by potential sweeps and chronoamperometry, are discussed and correlate well with the physical properties. This study, carried out in the absence of composition and particle size effects, shows that the electrocatalytic activity towards ethanol oxidation is strongly influenced by the changes in the amounts of Sn in alloyed and oxidized forms, and that the increase in the amount of alloy at expense of the oxides improves the catalytic activity.     

一种从Al-Si活塞合金中除Ca的新方法

研究了一种从Al-Si活塞合金中除Ca的新方法.结果表明：向经P变质处理的合金熔体中加入Al-C中间合金能使Ca含量显著降低,并使P的变质效果得到恢复.