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。     

氢含量对Al-P中间合金变质效果的影响

利用测氢仪等测试手段研究了 ZL1 0 9熔体中氢含量对 Al- P中间合金变质效果的影响。结果表明 ,在相同的铸造条件下 ,变质后合金中熔体氢含量越高 ,初晶 Si晶粒的平均晶粒尺寸和最大晶粒尺寸越大。保温时间过长合金熔体有吸氢倾向 ,初晶 Si尺寸有增大趋势。在精炼处理充分的条件下 ,Al- P中间合金的变质效果可保持 3 0小时不失效     

Al—P中间合金变质剂在Al—Si活塞合金中的应用

在生产条件下比较了用Al-P中间合金与磷盐变质剂处理共晶和过共晶Al-Si合金的工艺特点、变质效果、力学性能和综合成本等，结果表明：使用Al-P中间合金操作方便，变质效果好、且稳定、力学性能也有不同程度的提高，而且该中间合金无渣、无污染，其使用可以实现生产过程的“零时间”变质处理，节约能源，提高生产效率，提高合金的实收率，降低产品的综合成本，有着良好的应用前景。     

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。     

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。     

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。     

PCD 刀具在 LH92 型稀土过共晶铝硅合金活塞加工中的应用

分析了ＬＨ９２型稀土过共晶铝硅合金活塞和ＰＣＤ（多晶人造金刚石）刀具各自的特性，介绍了国外ＰＣＤ刀具在铝合金加工中的应用实例和笔者采用ＰＣＤ刀具在ＬＨ９２型稀土过共晶铝硅合金活塞精加工中应用时选用的刀具几何参数、切削用量及取得的效果。实践表明，采用ＰＣＤ刀具取代ＹＧ６Ｘ硬质合金刀具后，产品尺寸精度、生产率、成品率、刀具寿命都有明显的提高。     

弯管和文丘里管组合结构燃烧器内气固两相流动的数值分析

通过数值计算方法研究了弯管和文丘里管组合结构燃烧器的浓淡分离特性,分析了煤粉颗粒直径和煤粉密度变化对燃烧器出口浓淡分离特性的影响．结果表明：弯管和文丘里管组合结构的燃烧器既可以实现浓淡分离,又可以达到煤粉浓侧气流不贴壁和中间给粉的效果;当煤粉颗粒直径为10μm时,浓淡分离效果不明显;当颗粒直径为50μm时,分离效果较好,并且浓度核心的最大煤粉浓度随着St的增大而增大;当颗粒直径为100μm时,随着St的增大,出现了多个浓度核心．     

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…     

活塞用稀土过共晶铝合金的研究

本文研究了用混合稀土元素制取内燃机活塞用过共晶铝合金材料,解决了成分配方、熔炼变质、浇铸、热处理和加工刀具等各项关键技术问题。试验证实该合金的热膨胀系数低,耐磨性能优良,高温强度较高,尺寸形状稳定性良好,从而可降低内燃机活塞与气缸套的配合间隙,改善柴油机窜机油、窜气、冷车敲缸、噪声、振动问题。     

Influence of alloying on the catalytic performance of Ni–Al catalyst prepared from hydrotalcite-like compounds for methane decomposition

Cobalt-, iron-, and copper-substituted nickel-aluminum hydrotalcite-like compounds (Ni_2.7Co_0.3Al, Ni_2.7Fe_0.3Al, Ni_2.7Cu_0.3Al HTlcs) have been synthesized and used as precursors to prepare Ni–Co, Ni–Fe, and Ni–Cu alloy catalysts for methane decomposition. The catalysts before and after reaction were characterized with various techniques including XRD, H₂-TPR, HAADF-STEM-EDX, SEM, TEM, and Raman. The characterization results indicate that upon calcination HTlcs are transformed into a mixed oxide solid solution, where cobalt, copper, and iron ions are incorporated into the nickel oxide, and the reduction treatment leads to composition-uniform alloy particles. In methane decomposition at 600 °C, alloying Ni with Co, Fe, and especially Cu is found to enhance the catalytic life and carbon yield. The order of activity is Ni_2.7Cu_0.3Al >> Ni_2.7Fe_0.3Al > Ni_2.7Co_0.3Al > Ni₃Al in terms of carbon yield, highlighting that Ni–Cu alloying is the most effective. Besides, Ni–Cu alloying remarkably changes the carbon morphology, giving carbon nanofibers as the main product. TEM and STEM measurements suggest that Ni–Cu alloy particles are readily aggregated into big particles (>60 nm) under the reaction conditions, which may be responsible for the significant effect of Ni–Cu alloying.     

高速铰削双层合金材料的硬质合金铰刀

阐述叶片叶轮两种不同性能合金钢装配后的铆钉孔铰削问题,论述了加工铆钉孔用铰刀材料选择及刀具结构和几何角度设计,给出加工铆钉孔的工艺参数,说明了使用效果。     

Self-standing foam-like Pd-based alloys nanostructures for efficient electrocatalytic ethanol oxidation

In this work, self-standing binary porous PdM (M = Ni, Fe and Co) foam-like nanostructures are rationally designed by a rapid and one-step aqueous-solution method, including ice co-reduction of metal precursors using sodium borohydride. Amongst the tested PdM nanostructures, the PdNi nanostructures delivered a superior alkaline ethanol oxidation reaction (EOR) activity and stability than those of PdFe, PdCo, and commercial Pd/C catalysts. The EOR mass activity of PdNi (4.81 A/mg_Pd) was 1.32, 1.51, and 24.05-folds of PdFe (3.62 A/mg_Pd), PdCo (3.19 A/mg_Pd) and Pd/C (0.2 A/mg_Pd), respectively based on equal Pd mass loading. This was attributed to the lower synergetic effect of PdNi, which enhanced activation/dissociation of H₂O to afford OH- species required for fast EOR kinetics; meanwhile, porous foam-like nanostructure improved electron mobility and increased accessible active sites. This study reveals that low synergism in porous PdM nanocrystals is beneficial for augmenting the EOR activity, which may allow the design of other binary Pd-based alloys for various electrocatalytic reactions.     

硬质合金铰刀加工铜镍合金

阐述铜镍合金管板孔铰削问题，论述了加工该铜镍合金管板孔用铰刀材料选择及刀具结构和几何角度设计，给出加工铜镍合金管板孔的工艺参数，说明了使用效果。     

合金加料系统及智能控制

主要介绍炼钢合金加料系统的组成及其功能,合金加料系统自动控制。     

Hydrogen release from hydrolysis of borazane on Pt- and Ni-based alloy catalysts

Two types of Pt- and Ni-based alloy catalysts were synthesized and comparatively tested for hydrogen generation from aqueous borazane (ammonia- borane, _BH3NH3)${\mathrm{BH}}_3{\mathrm{NH}}_3)$ solution. The experimental results demonstrated that hydrogen release rates from some of the Pt alloys such as PtRu and PtAu are nearly 9 times higher than those from pure Pt surface, and similarly, most of the Ni alloy catalysts exhibit greatly enhanced catalytic activities than pure Ni catalyst. Particularly, hydrogen release from NiAg-catalyzed _BH3NH3${\mathrm{BH}}_3{\mathrm{NH}}_3$ hydrolysis can complete quickly at room temperature showing a stable hydrogen yield at _H2/_BH3NH3ratio=2.9${\mathrm{H}}_2/{\mathrm{BH}}_3{\mathrm{NH}}_3\mathrm{ratio}=2.9$ (molar ratio), corresponding to 8.7 wt % hydrogen release. Since the Ni alloy catalysts are less costly and highly efficient, it is feasible to use the Ni alloy catalysts for practical hydrogen generation in portable applications.     

Ethanol oxidation on carbon supported (PtSn)alloy/SnO2 and (PtSnPd)alloy/SnO2 catalysts with a fixed Pt/SnO2 atomic ratio: Effect of the alloy phase characteristics

To evaluate the effect of the alloy phase characteristics on the ethanol oxidation activity, carbon supported (PtSnPd)_alloy/SnO₂ catalysts were prepared and their electrocatalytic activity compared with that of carbon supported (PtSn)_alloy/SnO₂. Pt-Sn-Pd/C samples in the atomic ratio (1:1:0.3) and (1:1:1) were characterized by energy dispersive X-ray (EDX) analysis, X-ray diffraction (XRD) and high-resolution transmission electron microscopy (HRTEM). XRD analysis shows the presence of fcc Pt reflexions, shifted to lower angles, and SnO₂ reflexions. By comparison with the XRD patterns of carbon supported Pt-Sn (1:1) and Pt-Pd (3:1) samples, prepared by the same method, the formation of ternary PtSnPd alloys is postulated. The crystallite size of the ternary catalysts is smaller than that of both binary Pt-Sn/C (1:1) and Pt-Pd/C (3:1) catalysts. Chronoamperometry experiments and tests in direct ethanol fuel cells of the as-prepared catalysts shows that the activity for ethanol oxidation of (PtSn)_alloy/SnO₂ is higher than that of (PtSnPd)_alloy/SnO₂. This result, obtained with the same Pt/SnO₂ atomic ratio in all the samples, indicates the critical role of the alloy phase characteristics of these catalysts on their activity for ethanol oxidation.     

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。