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。     

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。     

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。     

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.     

过共晶Al—Si合金初晶硅的细化

Al—Si铸造合金中初晶硅的细化可以通过往溶液中添加磷来实现.根据实际知识,在溶液中产生的AIP可作为初晶硅形成的晶核.目前铸造生产是以往熔炉内加Cu—P中间合金的方式来加磷.但是这种加磷的方法有一些缺点.因为形成AIP需要很高的溶液温度和很长的保温时间.这些条件会引起溶液中氢含量的增加和磷对炉衬的污染.这里介绍一种新的AlCuP中间合金棒,它包含预制的AIP.这种棒的细化效果,在加入后立刻开始,并且显著减少了磷的添加比率.采用这种方式,可以在正常浇注温度下,于半连续铸造和锭模铸造时把棒加到流槽中.这样就避免了上面提到的缺点.     

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。     

纳米TiO2对Mg-15%Mg2Ni复相合金吸放氢性能的影响

用扩散烧结制备Mg2Ni合金，然后与Mg粉和不同比例(质量百分比分别为0．5％，1.5％，2．5％)的纳米TiO2混和球磨得到纳米Mg—Mg2Ni—TiO2复合储氢材料。对复相合金进行储氢性能研究时发脱，其中添加0．5％TiO2的试样可以在393K，4MPa的条件下4min内吸氢，并能在503K，0．1MPa条件下15min内放氢，放氢量为4．1％；随着温度升高，复合储氢材料放氢量和放氢速度得到提高，在473K吸氢和503K放氢条件下，合金在15min内的放氢量达到5．6％。纳米TiO2对合金吸放氢动力学性能有促进作用。复合储氢材料中增加TiO2含量，加快了放氢速度，略微降低了放氢量。     

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。     

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。     

The influence of melt hydrogenation on Ti600 alloy

In this paper, melt hydrogenation, which is a new hydrogen treatment method, was used to hydrogenate Ti600 alloy, the relationship between the hydrogen partial pressure and the hydrogen content was built by analyzing experimental data, and microstructure was observed and mechanical properties was tested. It was found that hydrogen addition made the thickness of the solidified shell thinner and a big temperature gradient existed from the top to bottom surface of the alloy melt. With increasing hydrogen partial pressure, the directional solidification structure can be formed in the Ti600 alloy ingots. Microstructure of Ti600 alloy was modified significantly and the amount of α′ and β phases after melt hydrogenation. When increasing the content of hydrogen to 7.2 at.%, γ hydride was obtained in Ti600 alloy. The flow stress and yield stress decrease with increasing the hydrogen content.     

Hydrogen solubility in molten TiAl alloys

In this work, the hydrogen solubility in a titanium–aluminium (TiAl) binary alloy melt was investigated through a theoretical analysis and the results compared subsequently with values determined experimentally. Determination of the theoretical values of hydrogen solubility is based on a modified version of Sievert’s law, in which hydrogen solubility is related to the activity coefficient of the alloy melt and the hydrogen solubility in pure liquid metals. The activity coefficient is obtained in terms of the free volume theory, in which excess entropy is sufficiently taken into account. The experimental values of the hydrogen solubility in the two alloy melts, Ti45Al and Ti47Al, were determined to validate the calculated values. This was performed using hydrogen charging apparatus. The experimental values obtained were in good agreement with the calculated values.     

Influence of the composition of lithium-based alloys,non-aqueous electrolytes and cycling conditions on the anode properties

The reversible work of a lithium-based anode in non-aqueous electrolytes of different compositions has been investigated. The electrochemical properties of anodes of Li, binary LiAl alloys, ternary LiAlCd, LiAlSi, LiAlBi alloys were compared. The concentration range of aluminium in the alloys was used in accordance with a binary constitutional diagram. In a series of binary alloys with an Al content 5, 16.8, and 22.5 mass%, in the process of anode ‘ageing’, the alloy containing 16.8 mass% Al is passivated to a greater extent. Hence, cycling efficiency of lithium deposits changed. The increase in charge-current density and the discharge-current density decrease raise the efficiency of lithium deposits. Comparison of the results of impedance measurements and galvanostatic cycling showed that the efficiency of galvanostatic cycling is higher when the active component of impedance is lower. The polarization of cathode process (deposition) and anode process (dissolution) decreases significantly in a series of lithium anodes: anodes on the basis of binary LiAl alloys and anodes based on ternary alloys. Lithium insertion into the structure of ternary alloys proceeds considerably easier than into lithium or binary lithium-aluminium alloy structures. It may be conditioned by the binary alloy passivation in the electrolyte and by the less passivating film resistance on the ternary alloys.     

Microstructural evolution and hydrogen storage properties of a Ni-modified Mg15Al alloy

On the basis of modification of transition metals on Mg-Al hydrogen storage alloys, Mg15Al5Ni alloy with Ni content of 5 wt% has been prepared by high energy ball mill. The results show that Ni particles uniformly distribute on the surface of particles, while several Ni particles are embedded inside alloy particles. These Ni particles tend to redistribute after hydrogenation. The phase composition analysis reveals the formation of stable Al₃Ni₂ phase in Ni-modified alloy after hydrogenation. The hydrogen absorption performance of Mg15Al5Ni alloy has been improved by introducing Ni, which can absorb 4.36 wt% hydrogen within 5 min at 350 °C. Meanwhile, the activation properties of Mg15Al5Ni alloy can be obviously deteriorated due to the addition of Ni. However, uniformly distributed Al₃Ni₂ nanocrystals with grain sizes around 10 nm hinder grain growth of hydrides, ameliorating hydrogenation kinetics of Mg15Al5Ni alloy. Besides, the modified effect of Ni on hydrogenation kinetics of Mg15Al5Ni alloy has been also discussed in this work.     

Effect of thermo hydrogen treatment on lattice defects and microstructure refinement of Ti6Al4V alloy

An investigation of a rolled Ti6Al4V alloy after thermo hydrogen treatment was performed. The effect of hydrogen content on the types and amount of lattice defects, the microstructure refinement after hydrogenation–dehydrogenation processing and the refining mechanisms were studied. The results show that the types of defects are at first vacancies and dislocations, and then they are mainly dislocations with increasing of hydrogen content. The amount of defects increases gradually with increasing of hydrogen content. After thermo hydrogen treatment, the rolled microstructure of Ti6Al4V alloy is refined.     

Hydrogen effect on Ti-6.5Al-3.5Mo-1.5Zr-0.3Si parts produced by electron beam melting

In this work, the hydrogen sorption kinetics as well as the hydrogen effect on phase transformations, structure and properties of additively manufactured Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy using electron beam melting (EBM) were studied. In situ X-ray diffraction complex was used to analyze phase transitions in the EBM Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy under hydrogenation in gas atmosphere. The EBM mode is found to affect significantly on the microstructure and the rate of hydrogen sorption by Ti-6.5Al-3.5Mo-1.5Zr-0.3Si alloy during hydrogenation at a temperature of 650 °C. The measurements have shown that the highest rate of hydrogen absorption is observed in samples manufactured at the beam current of 3 mA and the scanning speed of 150 mm/s. Hydrogenation of the samples leads to redistribution of alloying elements in the titanium alloy resulted in the formation of aluminum-rich α₂-Ti₃Al intermetallic phase and hydrides precipitation.     

Study on the influence of Mg content on the risk of hydrogen production from waste alloy dust in wet dust collector

We use a proprietary automatic Al–Mg alloy–water reaction test apparatus to compare the hydrogen evolution profiles of Al-xMg (x = 10%,20%) with different particle sizes, characterize the waste Al-xMg alloy dust particles before and after reaction through SEM, EDS, and XRD, and present a three-stage four-step hydrogen evolution model of Al-xMg (x ≤ 35%) alloy dust particles. It is discovered that the reaction of the Al–Mg alloy in water is a hydrogen evolution–adsorption–slow diffusion process. The particular β-Al₃Mg₂ in Al-xMg (x ≤ 35%) will adsorb the resulting hydrogen to form MgH⁺ and adhere to the surface of the particles. As the Mg content in the alloy increases, the hydrogen evolution reduces. The entire process lasts around 5–6 h, with maximum hydrogen conversion rate of 54% (Al–10%Mg, d (50) = 12 μm, α = 0.544). Our hydrogen evolution model provides very useful theoretical references for avoiding hydrogen explosion in Al–Mg alloy manufacturing facilities.