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。     

含钪铝合金的开发应用前景

介绍和分析了新型合金化元素钪对铝合金性能的影响和当前含钪铝合金的发展动向及应用前景，同时提出并讨论了我国含钪铝合金的发展战略，建议加速掌握以非高纯氧化钪为原料生产Ａｌ－Ｓｃ中间合金的工业技术和大力开展含钪铝合金的开发应用，尽快把我国含钪铝合金工业的生产体系建立起来。     

铝钪中间合金的制备技术

钪是铝合金最强的变质剂和加工半成品最有效的抗再结晶剂,添加微量钪可以改善传统铝合金的综合性能。但是钪的熔点高达1541℃,化学性质活泼,制备含钪铝合金时,钪必须以中间合金的形式加入,钪中间合金因此成为制取铝钪合金的关     

铝-钪合金的性能与应用

对铝-钪中间合金的制备工艺与钪的性能,以及含钪的变形铝合金的组织与性能作了全面的介绍。由于含钪的铝合金有良好的综合性能,因而在各个领域均有应用,但钪的价格高昂,对其应用又有所制约。     

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。     

Sc在铝合金中的微合金化作用机理

综述国内外含钪铝合金的研究历史与现状,论述钪的细化合金晶粒、提高再结晶温度、改善合金力学性能、提高抗腐蚀性能以及改善焊接性能的作用机理,重点介绍第一性原理、嵌入原子势模型和经验电子理论对含钪铝合金形成焓与结合能等热力学性质计算以及相稳定性研究的最新进展,最后论述钪对改善铝铜系合金综合性能的作用机制。     

铝钪合金的研究与开发

钪是到目前为止所发现的对铝合金最为有效的合金化元素.本文综述了国内外铝钪合金的研究现状,介绍了钪在铝合金中的作用.简要阐述了铝钪合金的开发应用前景.     

含钪铝合金研究进展

含钪铝合金是一类新型铝合金材料,主要介绍了钪元素全面提升铝合金综合力学性能,耐腐蚀性能,焊接性能等方面的效果。本文研究Sc对铝合金力学性能、耐腐蚀性能的影响,给出提高焊接性的影响因素,结合国内外含钪铝合金的研究成果,为今后含钪铝合金材料在国内该领域的发展提出建议。     

加钪对Al-Zn-Mg-Cu-Zr合金组织性能的影响

本文研究了微量钪对Al-Zn-Mg-Cu-Zr合金组织及性能的影响。钪在铝合金中主要以两种形式的化合物存在，一种是合金凝固时从熔体中析出的一次Al2(Sc，Zr)相，另一种是铸锭均匀化时析出的二次Al2(Sc，Zr)相。前者是αa(Al)晶粒细化剂，可有效细化铸态晶粒；后者可强烈牵制晶粒内位错及亚晶界，有效阻止热轧、退火或固溶处理过程中的再结晶。钪是产生强烈析出强化的合金元素，同不加钪的铝合金相比，含0．30％Sc的Al-Zn-Mg-Cu-Zr合金的抗拉强度和延性显著提高。     

美国NioCorp公司成功生产铝-钪中间合金

<正>近日,美国NioCorp等公司利用改进的冶金工艺成功生产出铝钪中间合金,有望成为潜在的中间合金商业生产途径。铝钪中间合金是将钪元素引入到铸造和锻造铝合金熔体之中,能够使铸造和凝固过程的晶粒细化,改善焊接性能,最大程度     

微量钪对Al-Mg-Mn合金组织与性能的影响

采用铸锭冶金法制备了Al-Mg-Mn和Al-Mg-Mn-Sc两种合金，利用TEM和金相显微镜等手段研究了微量Sc对Al-Mg-Mn合金组织与性能的影响。结果表明：加入微量Sc可以提高Al-Mg-Mn合金的拉伸力学性能。在电镜下可以观察到，在Al-Mg-Mn合金中加入微量Sc可以形成大量弥散的Al3Sc粒子，这些粒子对位错具有钉扎作用。     

微量Sc、Zr对Al-Mg合金的组织和力学性能的影响

利用金相显微镜、扫描电镜和透射电镜研究了添加微量 Sc、Zr的 Al- Mg合金不同处理态的显微组织与力学性能。结果表明 :微量 Sc、Zr对 Al- Mg合金的铸态组织有强烈的细化晶粒作用 ;对力学性能具有明显强化 ,其强化机制为细晶强化、亚结构强化和弥散相质点的直接强化作用。     

Microstructures and Properties of Al-Zn-Mg-Cu-Zr Alloys with Minor Scandium

The microstructures of Al-Zn-Mg-Cu-Zr al- loys with minor Sc were studied by using optical microscope（OM）, scanning electron microscope （SEM） and transmission electron microscope（TEM）. The tensile mechanical properties and electric conductivity of the studied alloys under different treatment conditions were tested. The results show that adding minor Sc can greatly fines the grain size of the Al-Zn-Mg-Cu-Zr alloy ingots and obviously improves the tensile properties and electric conductivity of the alloys. The strengthening mechanism is considered as fine grain strengthening, sub-structure strengthening and dispersion strengthening by Al3 （Sc, Zr）.     

Homogenization and Recrystallization of Al-6Mg Alloys with and without Sc and Zr

ДрицМ .Е .[1,2 ] reportedthatscandium ,com paringwiththeotherrareelements ,isthemosteffec tiveadditiontopromotethestrengthofaluminumal loys .Thestrengthofas extrusionAl 6 5Mgalloyrodcontaining 0 .2 %Screaches 4 0 0MPa (σb)and 2 5 0MPa (σ0 .2 ) ,higherthanAl 6 5Mgalloywithoutscandiumonetime .Willey[3] fromAluminumCompa nyofAmericapatentedthefirstaluminumscandiumalloyin 1971.Since 70′soflastcentury ,theformerSovietUnionengagedcompletelyresearchonthepro ductionandapplicationofalum…     

Fluidity and Hot Cracking Susceptibility of A356 Alloys with Sc Additions

A356 with scandium (Sc) addition provides interesting results beyond costs. For the practical use of Sc, the effects of Sc on castability must be considered. Fluidity and hot cracking are important factors defining the castability of aluminum casting alloys. In the present work, the influence of Sc addition on the castability of A356 hypoeutectic Al–Si alloy was investigated, which was evaluated through fluidity and hot cracking susceptibility. The fluidity of the alloys was studied by measuring the total volume of solidified aluminum in a multi-channel mold. The hot cracking susceptibility of the alloys was evaluated by using a constrained-rod casting mold test. The results of the fluidity and hot cracking susceptibility test were supported by microstructural analysis. The results indicate that 0.2 wt% Sc addition significantly increases the fluidity of A356 alloy, due to the grain refinement and eutectic Si modification by changing the solidification mode. However, the fluidity slightly decreases when the Sc content increases to 0.4 wt% due to the formation of primary Al₂Si₂Sc intermetallic phase. The hot cracking of A356 alloy was completely diminished when Sc was added to the alloy.     

电解铝钪合金的热力学

简要介绍了铝—钪合金的优异性能 ,发展现状 ;提出了利用未经高度提纯的氧化钪 ,直接在电解槽中电解铝—钪合金的工艺方案 ;对该方案的反应热力学数据进行了计算 ,并利用Miedema模型对钪在铝中的活度系数进行了计算。结果表明 :在电解条件下 ( 12 2 3K) ,钪与铝共同析出时 ,在铝液中的平衡活度最大可以达到 2 33 %。加之钪与铝生成稳定的高熔点化合物 ,使钪在铝中的活度系数远小于 1,从而使在电解槽中直接生产含钪在 2 %左右的铝钪合金成为可能。     

Influence of crystallization conditions on the structure and modifying ability of Al–Sc alloys

The influence of the modes of thermal-and-temporal treatment and cooling rate of metallic alloys on crystallization regularities of Al–Sc alloys and their structure, properties, and modifying ability are established. Castings of Al–Sc alloy, which were prepared by the electrolysis of salt melts KF–NaF–AlF₃–Sc₂O₃ at 820–850°C, are used as the initial charge for casting. It is established that, by varying the magnitude of melt overheating and casting temperature, it is possible to vary the crystal shape, amount, and size in wide limits. The modifying action of cast and rapidly quenched master alloys, as well as the master alloy produced by electrolysis, is tested for Al–4.5% Cu alloy. The largest effect of milling the structure of the Al–4.5% Cu–0.4% Sc alloy is attained when using the rapidly quenched master alloy.     

微量钪(Sc)对5A01合金性能与显微组织的影响

研究了在5A01合金基础上添加0．2％Sc和0．3％Sc后合金的显微组织、力学性能、腐蚀性能及焊接性能。结果表明，微量Sc的加入，初生Al3Sc或Al3（Sc，Zr）粒子可成为有效的非均质晶核，大大地细化合金的铸态晶粒，次生Al3Sc或Al3（Sc，Zr）粒子，能有效地钉轧位错和亚晶界，稳定亚结构并强烈抑制合金的再结晶。因此，加入Sc后的试验合金基体及焊接强度提高，腐蚀性能和焊接性能与5A01合金相当甚至更好。     

Sc对7056铝合金组织和性能的影响

对铸态合金进行了均匀化处理、挤压、固溶处理和时效处理，通过分析合金的化学成分，观察合金在不同状态的显微组织及析出相透射电镜(TEM)形貌，测试合金在热处理后的硬度和拉伸性能，研究了向7056铝合金中加入质量分数0.2%的Sc对合金组织和性能的影响.实验结果表明，Sc元素的加入可以明显细化组织晶粒，铸态晶粒由100~500 μm下降到50 μm左右；Sc元素的加入对合金的塑性有大幅度提高，时效处理后，合金的断后伸长率从10.82%增加到了13.60%；但屈服强度却由668 MPa下降到657 MPa.通过综合计算晶粒大小、析出相强化等因素，详细分析了Sc元素加入引起7056铝合金峰时效态屈服强度下降的原因.理论计算显示，向合金中加入质量分数0.2%的Sc元素时，峰时效处理后，合金的强度值会下降12.005 MPa，与试验值11 MPa接近.研究得到7056铝合金最佳的单级时效制度为120℃+16 h，峰值硬度和强度为195.2 HV和714 MPa，此时合金中主要强化相为圆盘状和短棒状的MgZn₂相，大小约为4~6 nm，同时存在球状的Al₃Zr相，大小约为20 nm.      

Thermodynamics-Based Computational Design of Al-Mg-Sc-Zr Alloys

Alloying additions of Sc and Zr raise the yield strength of Al-Mg alloys significantly. We have studied the effects of Sc and Zr on the grain refinement and recrystallization resistance of Al-Mg alloys with the aid of computational alloy thermodynamics. The grain refinement potential has been assessed by Scheil–Gulliver simulations of solidification paths, while the recrystallization resistance (Zener drag) has been assessed by calculation of the precipitation driving forces of the Al₃Sc and Al₃Zr intermetallics. Microstructural performance indices have been derived, used to rank several alloy composition variants, and finally select the variant with the best combination of grain refinement and recrystallization resistance. The method can be used, with certain limitations, for a thermodynamics-based design of Al-Mg and other alloy compositions.