铝钪合金的现状与展望

概述了钪对铝合金性能的影响,并对铝钪合金发展的历史和现状进行了概括。论述了铝钪合金的制备方法及铝钪合金的性质,如高强度、热稳定性高,焊接性、耐腐蚀性优良等。介绍了几种常用的铝钪合金,评述了铝钪合金的发展前景并指出了我国铝钪合金的研究方向。     

TiAl基合金的组织演变

综述了TiAl基合金中几种常见的组织演变,着重论述了变形TiAl基合金在热处理过程中的晶粒长大及动力学、TiAl基合金在冷却时层状组织的形成和全层状TiAl基合金在高温时的非连续粗化这3种组织演变。     

铝、镁、钛合金材料在汽车工业中的应用和发展

阐述了现代汽车为节能、环保而开始大量采用铝、镁、钛舍金材料；介绍了铝、镁、钛舍金材料的性质特点，采用铝、镁、钛合金材料制造的汽车部件；并指出铝、镁、钛材料在汽车工业中的应用和发展前景。     

钇在耐热镁合金中的应用

概述了镁合金的耐热性能及合金化设计依据,介绍了Y在耐热镁合金中的应用,探讨了Y对镁合金耐热性能的影响作用,展望了耐热镁合金的发展方向,旨在为耐热镁合金的开发提供思路和依据.     

西北有色金属研究院研制的部分钛合金及产业化

西北有色金属研究院是我国重要的钛合金研究与开发的单位之一，近40年来，一直致力于钛合金的研究、开发及产业化，仿制与创新研制出近60种钛合金，一些仿制的钛合金已大批量生产，获得成功的应用，如纯Ti、TC4、半TC4、Ti．Pd、Ti．Mo．Ni、BT20、BT16、HT7M等等；一些创新研制的钛合金也已获得成功的应用和批量生产，如TC21、Ti75、Ti31、CT20、Ti12LC等等，为我国钛合金的发展做出了突出贡献。本文简要综述了西北有色金属研究院仿制与创新研制的部分钛合金及其产业化。     

Recent metallic materials for biomedical applications

Metallic biomaterials are mainly used for replacing failed hard tissue. The main metallic biomaterials are stainless steels, Co-based alloys, and titanium and its alloys. Recently, titanium alloys are getting much attention for biomaterials. The various kinds of new high strength α+β and low-modulus β-type titanium alloys composed of nontoxic elements, such as Nb, Ta, Zr, etc., are developed for biomedical applications because of the toxicity of alloying elements and lack of mechanical biocompatibility of conventional titanium alloys, such as Ti-6Al-4V. Recent research and development in other metallic alloys, such as stainless steels and Co-based alloys, also will be discussed.     

抗蠕变耐热镁合金的发展现状

讨论了镁舍金抗高温蠕变机理和提高镁合金抗高温蠕变的途径,重点介绍了Mg-Al系、Mg-Zn系和Mg-RE系耐热铸造镁合金的研究现状;对高性能耐热镁合金的发展趋势提出了一些见解,认为应该进一步优化合金元素,以解决铸造镁舍金在耐高温、抗蠕变等方面存在的问题。     

The effect of fluid flow on eutectic growth

The effect of fluid flow on eutectic microstructure is systematically examined in Al-Cu alloys of compositions varying from 19.5 to 45.0 wt pct Cu. It is shown that significantly different fluid-flow effects are present in hypo- and hypereutectic alloys, since the modes of convection are different in these two cases. In hypoeutectic alloys, the rejected solute is copper, which is heavier than aluminum, and fluid flow gives rise to radial solute segregation in cylindrical samples. In hypereutectic alloys, a lighter aluminum is rejected that causes a double diffusive convection and gives rise to macrosegregation. These composition variations are shown to produce nonuniform microstructures that vary either radially (in hypoeutectic alloys) or axially (in hypereutectic alloys) and can give rise to a single phase-to-eutectic, lamellar-to-rod eutectic, or rod-to-lamellar eutectic transition in a given sample. Composition measurements are carried out to characterize solute segregation due to fluid flow. The fluid-flow effect on eutectic spacing in eutectic or near-eutectic alloys is found to be very small, whereas it increases the eutectic spacing in hypoeutectic alloys for a given local composition and it can increase or decrease the spacing in hypereutectic alloys, depending on the microstructure and solidification fraction. Theoretical models, based on diffusive grwoth, are modified to predict the spatio-temporal variation in eutectic microstructure caused by fluid flow.     

含钪铝合金及其应用

钪改性的铝合金是一类高性能新型铝合金。钪对铝合金有明显的晶粒细化作用,提高了铝合金强度,抑制了再结晶,强化了焊缝,消除了焊缝出现的热裂。这类合金还显示出优良的抗腐蚀性能。本文还综述了含钪铝合金在军事和民品方面的应用。     

含Cu镁锂合金组织与性能调控研究进展

镁锂合金具有超低密度、极高的比强度与比刚度、优异的电磁屏蔽性能及阻尼性能,目前广泛应用于追求轻量化的航空航天、新能源汽车、电子产品、生物医疗等领域。由于合金元素镁和锂均为活泼金属,在服役过程中镁锂合金会存在多种形式的腐蚀过程,同时二元镁锂合金强度较低,以上两点严重制约了其广泛应用。耐蚀涂层可以有效提高镁锂合金的腐蚀抗力,含铜镀层被证实能够提升镁锂合金耐蚀性。改善镁锂合金强度的工艺主要有合金化、热处理、加工变形等,其中合金化是最基本的强化手段。Cu合金化可以对镁锂合金中的组织与性能进行调控,改善镁锂合金的强度。本文对含Cu镁锂合金的研究进展及其应用情况进行综述,总结了目前含Cu镁锂合金耐蚀与力学性能的相关研究成果,重点梳理了铜元素在镁锂合金中的作用,为含Cu镁锂合金的实际应用提供一定的理论指导。     

快速凝固耐热铝合金的发展及展望

对耐热铝合金的发展进行了回顾,综述了耐热铝合金的性能及其影响因素,分析了目前发展中存在的问题,并对其今后的发展动向提出了看法。     

Ni/MH电池用AB_5型贮氢合金电极研究进展

综述AB_5型贮氢合金电极的研究现状, 总结了目前改善AB_5型稀土系贮氢合金综合性能的方法.详细介绍了合金成分优化,控制合金组织结构,形成第二相和表面处理等方面的研究进展.通过这些途径,可以对AB_5型贮氢合金进行深入研究,从而进一步提高合金的性能.     

Deformation properties of sintered tungsten-based heavy alloys

The deformation properties of tungsten-based sintered alloys are studied. Plasticity diagrams are plotted for these alloys at deformation temperatures up to 900°C and various state-of-stress schemes. The properties of the tungsten-based sintered alloys are determined during alternating deformation. The joint action of the temperature (up to 900°C) and the state of stress on the ductility of the tungsten-based sintered alloys is analyzed. The results obtained are used to simulate damage accumulation for various methods of strain hardening of heavy alloys (rotational reduction, hydraulic forging, rolling in multiroll passes). Hydraulic forging is considered, and the limiting reductions are determined using the condition of impossible irreversible metal microfracture.     

Magnetic Entropy Change of （Gd1-xREx）5Si4（RE = Dy, Ho） Alloys

Magnetic Entropy Change of (Gd_(1-x)RE_x)_5Si_4(RE=Dy, Ho) Alloys     

快速凝固铝硅合金的制备、组织特征及断裂行为

快速凝固Al-Si合金是一种高性能结构材料,目前主要通过快速凝固/粉末冶金(RS/PM)和喷射沉积(SF)两种方法进行制备;此类合金具有超细化显微组织、成分均匀分布、非平衡亚稳相和过饱和固溶体及高密度位错等组织特征;其断裂方式主要呈脆性断裂。本文主要对上述内容进行综合评述     

Tin-based reactive solders for ceramic/metal joints

Contact angle measurements on silicon-nitride substrates were conducted on tin-based alloys, containing titanium and zirconium, to determine the suitability of these alloys as filler metals for low-temperature joining of ceramics. Titanium-containing alloys exhibited excellent wettability characterized by contact angles less than 20 deg, whereas the Zr-containing alloys exhibited contact angles around 50 deg. The superior wettability of the Sn−Ti alloys is attributed to the higher activity coefficient of Ti in Sn−Ti alloys. The liquidus temperature of the Sn−Ti alloys is in the 400°C to 600°C range. Hence, these alloys are expected to reduce the residual stress problem.     

贮氢合金进展

对贮氢合金的工作原理及应用,贮氢合金的基本类型及开发历史和发展趋势进行了综合评述。MmNi5系稀土合金和Laves相合金的开发应用已较为成熟,但其贮氢密度不高,高容量型的钒固溶体型合金和镁基合金是贮氢合金发展的新趋势。目前主要通过添加合金元素、开发制备工艺,改进微观相组织结构并兼以适当的表面处理,以提高钒固溶体型合金和镁基合金常温常压下的吸放氢特性及活化性能。     

Phase equilibria in the titanium corner of hypoeutectic alloys in the Ti-Nb-Si-Al system

Physicochemical analysis methods have been applied to the phase equilibria in the Ti-Nb-Si-Al system in the region of alloys rich in titanium. It is found that the crystallization conditions for hypoeutectic alloys with constant 5 at.% aluminum content control the niobium contents up to 17.5 at.%, for which there are two groups. After the primary crystallization of the β phase in alloys in these groups, binary eutectics are formed with different intermetallic phases. The properties of the alloys are dependent on the phase compositions in the eutectic mixtures. The temperature and concentration stability of the phases have been determined. It is shown that a peritectic reaction may give rise to a second intermetallide phase in alloys approximating to equilibrium as a result of subsequent annealing, which does not affect the structure of the cast alloys.     

Tuning Cr-rich nanoprecipitation and heterogeneous structure in equiatomic CrFeNi medium-entropy stainless alloys

High-/medium-entropy stainless alloys(HESAs/MESAs)are a new kind of alloys with great potential to combine excellent properties from high-/medium-entropy alloys...     

钼-铼-镧合金微观组织及力学性能研究

通过固-液掺杂法在Mo-Re合金中加入稀土La₂O₃纳米颗粒制备得到Mo-Re-La合金, 将Mo-Re-La合金与Mo-Re合金、纯Mo的微观组织及力学性能进行对比研究, 得到如下结论: 在纯Mo中添加低含量Re元素(质量分数3.5%) 对Mo-Re合金有明显的细晶强化效果; 将La₂O₃纳米颗粒加入Mo-Re合金进一步细化和强化了Mo-Re-La合金。