钨铼合金制备方法和高温力学性能的研究进展

高性能W-Re-ThO2,W-Re-HfC系钨铼合金的制备和性能研究会促进其在电子、核能、航天和测温技术等领域的应用。详细归纳了W-Re-ThO2和W-Re-HfC两种钨铼合金采用的工艺路线和工艺参数,总结了两种合金在不同成分和加工状态下时的高温力学性能,最后探讨了铼效应对钨铼合金高温性能影响的规律。钨合金的研究目前在向细化、纯化和强韧化方向发展,粉末冶金法是制备钨铼合金合适的工艺路线,因此开展第二相粒子强化的钨铼合金组织和性能的研究是非常重要的研究内容和方向。     

钨铼合金研究进展

随着航空航天技术、核工业、电子工业的日益发展,对超高温材料提出了更为苛刻的要求,急需研制高温高强度结构件材料。钨铼合金具有高再结晶温度、低韧脆转变温度、优异的高温强度以及高温抗蠕变性能,得到了国内外学者的广泛研究。本文综述了钨铼合金的分类及制备方法,并对固溶强化钨铼合金、碳化物增强钨铼合金、氧化物增强钨铼合金的再结晶温度、高温强度、高温抗蠕变性能等进行了比较,认为碳化物（Hf C）增强钨铼合金具有更加优异的性能。因此,碳化物第二相粒子增强钨铼合金是钨铼合金的发展方向并且有必要对钨铼合金的先进制备技术、成分优化、组织调控、变形行为和机理等问题开展进一步研究。     

拉拔形变中铼元素固溶无序化对钨铼丝导电性能的影响

金属钨因其高熔点、高密度和优异的高温性能，在电子器件、加热元件和辐射防护等方面有着广泛应用。通过添加铼元素固溶形成的钨铼合金被广泛应用于真空电子器件的核心材料，也是迄今为止对钨材料进行韧化最为有效的手段之一。在钨铼丝性能研究中，对于钨铼合金服役性能最为关键的电阻率指标却鲜有研究和报道，本试验通过对不同拉拔形变量的纯钨丝及W-20%Re合金丝的力学性能和电阻率变化趋势进行系统性研究。研究结果发现，相较于纯钨丝的抗拉强度和电阻率均随拉拔形变量上升而升高的特点，W-20%Re合金丝的电阻率随形变量的增加出现了两个具有显著差异的阶段。通过进一步的透射电镜显微结构、高分辨电镜下元素分布特征对比分析发现，该现象是由高温拉拔形变过程中钨铼合金中铼元素的均匀无序化固溶所造成的。     

退火温度对钨铼合金组织和性能的影响

采用粉末冶金工艺制备了钨铼合金,通过拉伸性能测试、硬度测试、光学显微观察等手段,研究了退火温度对钨铼合金组织和性能的影响。研究表明：锻造后的钨铼合金室温抗拉强度为1620 MPa,断后伸长率为20%,维氏硬度为HV₃₀ 540。钨铼合金在1500℃时开始发生局部再结晶,1700℃时发生晶粒长大。钨铼合金的室温抗拉强度、维氏硬度随着退火温度的提高而降低,断后伸长率随着退火温度的升高先增大后减小。     

钨铼合金粉末制备研究进展

性能优良的W-Re合金制品广泛应用在航空航天、高温测量、核聚变和电子等领域。W-Re合金粉末制备是其合金制备的关键步骤。文章详细介绍了钨铼合金粉末的制备方法,对固-固混料法、固-液混料法、固-固高能球磨法和液-液混料法的特点进行归纳总结,并简单阐述了钨铼合金的发展和应用。     

激光粉末床熔化W-21Re-C合金的成形与微观组织研究

为了实现激光粉末床熔化技术(Laser Powder Bed Fusion,LPBF)成形钨的裂纹抑制,本研究通过添加铼元素和碳元素,成功制备了W-21Re-C合金,并对其成形性、微观组织和力学性能进行了研究。结果发现,LPBF制备W-21Re-C合金的成形窗口较窄,并存在一定数量的孔洞和裂纹缺陷,但相较于纯钨裂纹有所减少。LPBF成形W-21Re-C合金中形成了大量六方W₂C亚结构,在快速凝固的作用下,体系中微纳尺度亚结构呈现为枝晶结构和胞状结构。合金中铼元素主要以固溶形式存在于钨基体中,W₂C亚结构的枝晶臂间隙和胞壁处也存在一定的铼元素偏聚。在铼对钨基体固溶强化和W₂C胞状结构的共同作用下,LPBF成形W-21Re-C合金的显微硬度显著高于良好LPBF成形的纯钨。     

W-Re合金的制备与应用

钨铼合金具有更好的耐高温、延展性、低蒸汽压、低电子逸出功和低的韧脆转变温度等优异的高温力学性能,应用于各高温材料领域。结合近年相关研究,从制备钨铼合金粉体和钨铼合金块体两方面出发,综述了Re对钨基材料性能方面的改善效果以及合金制备方法,粉体制备方法有高能球磨法、混粉法、湿化学法和球化法,合金制备方法常见有放电等离子烧结法、气相沉积法、3D打印成型技术等,并结合其应用背景对制备工艺的研究现状及发展趋势进行展望。     

电感耦合等离子体原子发射光谱法测定镍基单晶高温合金中钨钽铪铼

镍基单晶高温合金中高含量的钨、钽、铪、铼等难熔元素,不仅对样品前处理造成阻碍,而且其元素间的光谱干扰会对测定结果造成严重影响。实验采用18mL盐酸-2mL硝酸-2mL氢氟酸溶解样品,再加入酒石酸可使样品溶液长期稳定存在。通过研究单晶高温合金中钨、钽、铪、铼的谱线干扰情况,选择W 207.911nm、Ta 240.063nm、Hf 282.022nm、Re 197.312nm作为分析谱线,采用基体匹配法配制标准溶液系列绘制校准曲线,使用电感耦合等离子体原子发射光谱法(ICP-AES)测定镍基单晶高温合金中钨、钽、铪、铼。各元素在线性范围内校准曲线线性关系良好,相关系数均不小于0.9997;方法检出限为0.0001%~0.0008%。按照实验方法测定DD6单晶高温合金样品中钨、钽、铪、铼,结果的相对标准偏差(RSD,n=11)为1.0%~2.5%;加标回收率为96%~102%。     

钨铼热电偶及其推广应用

<正> 前言钨铼合金有优异的性能,并且有了许多重要的特定用途。该合金系列是兼顾了金属钨和铼的优点,不仅熔点高、强度大、蒸汽压低、耐腐蚀性好、富有延性、加工性能优良,而且具有高的电阻率、低电阻温度系数,良好焊接特性、高再结晶温度、能产生高和稳定的热电势。因此除在电子、电真空、电光源用作电子材料和宇航、核能、高能物理、     

浅谈钨铼合金残料的回收问题

<正> 钨铼合金是富有良好延性的钨基合金,有广泛的用途。在制备WRe合金材料工艺过程中,不可避免产生不同形式的残料,有时尽管数量不大,但里面除钨外,尚含有价值的铼成分,极有必要予以回收利用。本文就我们生产WRe合金多年的实践,对WRe合金残料回收摸索了一些办法,在此简介,供用者参考。     

A Study of Scandia Doped Tungsten Nano-Powders

Scandia and rhenium doped tungsten powders were prepared by solid-liquid doping combined with two-step reduction method. The particle size of doped tungsten and distribution of scandia and rhenium were studied by SEM, EDS, XRD and granularity analysis. Experimental results showed that scandia distributed evenly on the surface of tungsten particles. Addition of scandia and rhenium decreased the particle size of doped tungsten, and the more the content of scandia and rhenium, the smaller the doped tungsten particles. Tungsten powders doped with 3 % Sc2O3 and 3 % Re （mass fraction） had an average size of about 80 nm in diameter. The mechanism of the decrease in the tungsten particle size was discussed.     

用XRF二元比例法测定钨铼合金中的钨和铼

本文叙述二元比例法对钨铼合金中钨和铼的快速分析方法及其特点,对方法的精度作了统计计算,并与强度比对浓度比的α系数校正方法的分析结果做了比较。通过人工模拟的合成试样用回收率计算来验证该方法分析结果的准确度。     

铼的生产与应用研究进展

铼是难熔金属，主要赋存于斑岩铜钼矿床的辉钼矿和黄铜矿中，铼含量在20～2000g／t之间。从钼精矿焙烧产出的烟尘和淋洗液中回收铼及从钼精矿氧压氧化浸出液中回收铼多采用溶剂萃取法和离子交换法。铼用作制取各种催化剂，如汽油重整、烯烃复分解等。铼也用于生产钼铼合金、钨铼合金、镍基超合金和铌铼合金等。铼的某些配合物用作抗癌药物。     

THE PREPARATION AND SOME PROPERTIES OF TUNGSTEN-RHENIUM-OSMIUM ALLOYS

Abstract

Two series of tungsten-rhenium-osmium alloys have been successfully prepared by powder-metallurgy techniques in sintered bar form. The first series, containing nominally 5% Re and up to 2·25% Os, are single-phase alloys consisting of an α solid solution of tungsten, rhenium, and osmium. The second series, containing nominally 26% Re and up to 11·3% Os, consist of the same solid solution up to ～1·67% Os, the higher osmium contents giving a two-phase alloy consisting of the α solid solution and the hard, brittle a phase. The two-phase alloys are of the age hardenable type and their properties are thus dependent on the thermal history.

The alloys containing ～26% Re and between ～0·69% and 4·5% Os are particularly prone to deformation twinning at room temperature, the tendency reaching a maximum at ～1·67% Os. This observation may be interpreted as an extension of the rhenium alloying effect, the double addition of rhenium and osmium giving an interactive as well as additive effect of Os atoms. Confirmation of the lower energy of the twinning planes is also apparent from the mode of precipitation of the σ phase on preferential planes in this composition range.     

Effect of palladium on the process of diffusional alloy formation and microstructure during the sintering of tungsten-rhenium powders with well-developed surfaces

Conclusions Low-temperature coreduction of tungsten trioxide and ammonium perrhenate can be employed as a means of preparing active tungsten-rhenium powders having well-developed surfaces and good sinterability. The action of an alloy formation activator manifests itself most strongly with active powders produced by the method of low-temperature coreduction of tungsten trioxide and ammonium perrhenate. Diffusional reaction between the tungsten and rhenium in such a case begins already during the reduction process. At temperatures of intense alloy formation phase interlayers of activator solid solutions form at grain boundaries in tungsten-rhenium alloys. As a result, the diffusional permeability of the boundaries to rhenium atoms grows, which activates the process of diffusional alloy formation.Translated from Poroshkovaya Metallurgiya, No. 1(205), pp. 36–40, January, 1980.     

Continuous Extraction of Nickel from Superalloy Scraps Using Zinc Circulation

A novel technique for the continuous extraction of nickel (Ni) from Ni-based superalloy scraps using molten zinc (Zn) has been proposed, and its feasibility was experimentally demonstrated. The newly developed approach allows for extraction of Ni metal directly from superalloy scraps with simultaneous separation of the Zn from the resulting Zn-Ni alloy. The optimal conditions for the extraction of Ni and separation of valuable elements such as rhenium (Re), tantalum (Ta), and tungsten (W) were determined by varying major process parameters including the reaction time and configuration of the reaction chamber. The proposed method has been successfully utilized for the production of the superalloy containing 62.8 mass pct of Ni and 15.5 mass pct of refractory metals (Re, W, and Ta). Under certain conditions, 41 pct of the Ni contained in the superalloy could be extracted at 1173 K (900 °C) over 48 hours, producing an alloy containing 84.0 mass pct of Ni and 0.2 mass pct of the refractory metals.     

Use of powders of the tungsten—Rhenium alloys for the preparation of impregnated cathode skeletons I. Densification and formation of porous structure in sintering of powders of tungsten-rhenium alloys

The effect of phase composition, fineness, and morphology of W-Re powders with different rhenium content on compaction, and formation of porous structure has been studied. Fine particle powders with a specific surface of 5–8 m²/g, mechanical mixtures of tungsten and rhenium powders, and W-Re alloy powders were used. Local nonuniform compaction is observed during sintering of powder mixtures and alloy powders. It was established that alloy powders and intermetallic powders have lower sintering activity.     

粉末冶金法制取低铼钼合金的研究

研究了用粉末冶金法制取Mo－3％Re合金的工艺．结果表明．粉末冶金法可以制得性能良好的Mo－3％Re合金．在混和料的制备中采用湿混或干湿混合．有利于Re的均匀分布；且3％Re的加入，可大大细化钼合金的晶粒．