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铼的生产与应用研究进展 总被引:9,自引:1,他引:8
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。 相似文献
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重量百分比含铼 4 0 %以上的钼 -铼合金可以承受很大的冷热变化 ,在极端恶劣的环境下钼 -铼合金仍有很长的使用寿命 ,在高温下仍可具有很高的强度 ,可以用作加热材料、热电偶的护套和真空炉用材料等 ,在许多情况下钼 -铼合金是最好的甚至是唯一的选择。但是 ,钼 -铼合金的生产困难 ,现在典型的生产方法是粉末冶金法 ,烧结钼 -铼合金需要的温度很高 ,通常需要在氢气保护气氛中在 2 2 0 0℃的高温下烧结。通过对钼 -铼合金烧结过程的深入理解 ,经过探索简化生产工艺可能降低制造成本 ,本次试验通过烧结钼 -铼合金粉和传统的混合粉制成的试样 ,… 相似文献
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钼铼合金的结构和性能 总被引:7,自引:1,他引:6
总结了钼铼合金研究的最新进展。典型的钼铼合金成份主要有M041Re,M044.5Re和M047.5Re。钼铼合金坯锭的制备一般采用粉末冶金和真空熔炼的方法。当铼含量低于29%时,铼在钼中固溶形成体心立方结构的α相,钼的晶格常数降低。当铼含量高于29%时,形成x相和σ相。钼铼合金合金的熔点、热性能、电性能介于纯钼和纯铼之间,铼可以提高钼的再结晶温度,降低其塑脆转变温度。铼既可以提高钼的强度,也可以大大改善其塑性。钼铼合金的加工硬化率介于纯钼和纯铼之间而靠近纯钼。 相似文献
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钨、钼和铼在现代技术中已广泛应用.在国外这些金属的应用构成于70年代末期趋于稳定.钨主要用于硬质合金、特殊钢及合金的生产;钼主要用于钢、铁合金生产中及以化合物形式而得到应用;铼主要用于催化剂及合金的生产(见表). 相似文献
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钼铼合金带材的组织和性能 总被引:1,自引:0,他引:1
选用熔炼的钼铼合金经过锻造、热拉、冷拉和轧制的方法制备钼铼合金带材,其规格为0.3mm宽0.03mm厚,对其组织和性能进行了研究。结果表明:加工态的拉断力是再结晶状态的2.5倍左右,为24.8N;而延伸率只是再结晶状态的1,3,为3.1%;随着退火温度的提高,钼铼合金的的拉断力直线降低,但延伸率在1723K,30min退火后却最高,金相结果表明1723K退火的钼铼合金带材发生了明显的再结晶。钼铼合金加工态拉伸时其断口表现为准解理断裂,退火后断口表现为明显的韧窝状。铼元素加入钼中,可以提高晶粒和晶粒之间的结合力,使得钼铼合金在拉伸下有很好的延伸率。同时钼铼合金在室温变形时,也容易发生孪晶变形,这一点不同于通常的钼合金。 相似文献
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K. B. Povarova A. E. Morozov A. G. Padalko A. A. Drozdov 《Russian Metallurgy (Metally)》2008,(2):155-158
The structure and hot hardness (at temperatures up to 1100°C) of RuAl-based powder alloys with 1–3 at % Ni, Mo, Re, or Ru are studied. The alloys are produced by the reactive sintering of cold-compacted bars and subsequent threefold isostatic pressing with intermediate annealing at 1500°C performed after the first hot isostatic pressing. The samples have a residual pore content of 1–2.5 vol % and are characterized by a micrononuniform distribution of base and alloying elements. The alloys with refractory metals, such as Re, Mo, or Ru, are found to have the maximum hardness at all temperatures under study. At low temperatures, the effect is more substantial; the hardness of the Re-containing alloys exceeds that of the other alloys by a factor of 1.3–3.6. The increase in the hardness related to solid-solution alloying becomes more substantial owing to the microinhomogeneity of the sintered powder alloys and weakens because of microporosity. Recommendations that allow the uniformity of the distribution of the base and alloying elements to be increased are given. 相似文献
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S. N. Ahuchkin V. T. Burtsev M. V. Zagumennikov V. V. Sidorov V. E. Rigin 《Russian Metallurgy (Metally)》2010,2010(1):13-17
The constrained drop method is used to study the surface tension σ of the following melts at 1773–1923 K and p Ar = 0.1 MPa: nickel of various grades (with various oxygen contents), binary Ni-Al (Re) alloys, and a complex Ni-Re-(W, Mo, Co) alloy. The value of σ of liquid nickel is shown to decrease with increasing oxygen content in it. The additions of aluminum (6%) and rhenium (3–7%) to nickel in binary alloys weakly change its surface tension. Alloying elements (W, Mo, Co) in Ni-Re-(W, Mo, Co) alloys insignificantly affect σ of their melts. 相似文献
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刘沙 《稀有金属与硬质合金》1997,(4):26-29
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. 相似文献
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Influence of Molybdenum and Rhenium Dopants on the Structure and Properties of NiAl–Cr–Co Cast Alloy
Sanin V. V. Aheiev M. I. Kaplanskii Yu. Yu. Petrzhik M. I. 《Russian Journal of Non-Ferrous Metals》2021,62(6):740-755
Russian Journal of Non-Ferrous Metals - Centrifugal SHS casting has been used for the production of NiAl–Cr–Co–X alloys, where X = 2.5–15.0 wt % Mo and up to 1.5 wt % Re.... 相似文献
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A castability model based on elemental solid-liquid partitioning in advanced nickel-base single-crystal superalloys 总被引:1,自引:0,他引:1
A castability model that accounts for the characteristic segregation behavior of constituent elements in Ni-base superalloys
has been developed and experimentally verified in production scale casting trials. The model ranks alloy compositions with
respect to their susceptibility to freckle formation during directional solidification. Thirty-nine distinct Ni-base single-crystal
superalloys encompassing a broad range of compositions were investigated to assess the influence of the constituent elements
on their solidification characteristics. Linear regression was applied to the fitted solid-liquid partition coefficients of
the major constituent elements to develop formulas capable of describing elemental interactions. The high-density refractory
elements Ta, W, and Re were found to segregate most severely during solidification. Increasing the amount of Cr and Mo in
high-refractory single-crystal alloys reduced the extent of W and Re microsegregation during solidification. This effect was
found to minimize the occurrence of freckle defects due to the corresponding decrease in the density inversion term, which
is effectively the driving force for thermosolutal convective instabilities known to cause macroscopic grain defects during
single-crystal solidification. Model predictions were validated using production scale casting trials where additions of 1.5
wt pct (1.9 at. pct) Cr and 3.0 wt pct (2.0 at. pct) Mo to a high-refractory superalloy more than halved the number of solidification-related
grain defects formed. These findings suggest that elemental interactions between Cr, Mo, W, and Re need to be considered when
optimizing alloys for high-temperature creep properties. 相似文献
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Walter R. Witzke 《Metallurgical and Materials Transactions A》1976,7(3):443-451
The mechanical properties of swaged rod thermomechanically processed from arc-melted Mo-2Re-Hf-C alloys containing as much as 0.9 mol pct HfC have been evaluated. The low temperature ductilities of these alloys were not influenced by the amount of HfC present but by the amount of Hf in excess of stoichiometry. Maximum ductility occurred at 0.2 to 0.3 at. pct excess Hf. At 0.3 to 0.5 mol pct HfC, alloy strength varied directly with the Mo content of extracted carbide particles, both decreasing as the amount of excess Hf increased. Additions of 2 at. pct Re had little effect on strength or ductility. Tensile and creep strengths of Mo-2Re-0.7Hf-0.5C alloy equaled or exceeded those of other high strength Mo alloys. 相似文献
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Walter R. Witzke 《Metallurgical and Materials Transactions A》1976,7(2):443-451
The mechanical properties of swaged rod thermomechanically processed from arc-melted Mo-2Re-Hf-C alloys containing as much
as 0.9 mol pct HfC have been evaluated. The low temperature ductilities of these alloys were not influenced by the amount
of HfC present but by the amount of Hf in excess of stoichiometry. Maximum ductility occurred at 0.2 to 0.3 at. pct excess
Hf. At 0.3 to 0.5 mol pct HfC, alloy strength varied directly with the Mo content of extracted carbide particles, both decreasing
as the amount of excess Hf increased. Additions of 2 at. pct Re had little effect on strength or ductility. Tensile and creep
strengths of Mo-2Re-0.7Hf-0.5C alloy equaled or exceeded those of other high strength Mo alloys. 相似文献
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以Mo粉、Nb粉、Si粉为原料,采用热压法制备(Mo<,1-x>Mb<,x>)<,5>Si<,3>(x=0,0.2,0.4)难熔金属硅化物合金,利用电化学测试及盐酸浸泡腐蚀实验,研究该合金在浓度为1 mol/L的HCl溶液中的腐蚀行为以及Nb含量对合金组织和耐蚀性的影响.结果表明,随Nb含量增加,(Mo<,1-x>Mb... 相似文献
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Gerhard Leichtfried Joachim H. Schneibel Martin Heilmaier 《Metallurgical and Materials Transactions A》2006,37(10):2955-2961
Mo-Re alloys containing between 5 and 47.5 wt pct Re were fabricated from Mo and Mo-Re powders by sintering and hot radial
forging. The mechanical properties of as-forged, stress-relieved, and recrystallized specimens were examined. Up to a concentration
of 41 wt pct Re, the Charpy ductile-to-brittle transition temperature decreased monotonically with increasing rhenium concentration.
Consistent with this, bend angles for fracture at T=−100 °C increased monotonically with increasing rhenium concentration. Between 10 and 41 wt pct rhenium, the room-temperature
tensile ductility of recrystallized Mo-Re remained nearly constant with values on the order of 35 to 45 pct. This result differs
from the low ductility values observed previously by Lundberg (1997) for compositions on either side of Mo-13 wt pct Re. 相似文献