合金元素对Mg-Li合金组织及性能的影响

合金化可以细化Mg-Li合金晶粒,从而提高综合力学性能,还可以改善合金耐蚀性、热稳定性。本文综述了Al、Zn、碱土元素和稀土元素等常用元素对Mg-Li超轻合金微观组织和性能的影响,一般情况下,Al和Zn主要通过固溶强化提高Mg-Li合金强度,碱土元素主要通过细晶强化来提高Mg-Li合金强度,稀土元素则通过细晶强化和金属间化合物的第二相强化来提高Mg-Li合金的综合性能。本文还指出了Mg-Li超轻合金合金化存在的问题及发展趋势。     

Mg-Li-Al合金光学金相(OM)的研究

通过对LA141和LAZ933两种Mg-Li合金使用不同的腐蚀剂来制取金相,实验结果获得了制取Mg-Li合金金相的可行方法.对Mg-Li合金的研究提供了切实可行的辅助方法,解决了Mg-Li合金研究过程中的一大困难.     

Mg-Li合金研究现状及其发展趋势

综述了Mg-Li合金的物理特性、晶体结构、组织和性能的特点以及常见Mg-Li合金的熔铸工艺(熔剂法、气体保护法、真空熔炼法、双重保护法、Mg-Li合金的精炼),着重介绍了Mg-Li合金的性能改善途径(元素强化、冷轧、时效强化、细晶强化)和Mg-Li基复合材料。简述了近些年来国内外学者对Mg-Li合金超塑性的研究成果,并对其发展趋势进行了展望。     

中国军机吊舱首次用国产Mg-Li合金制造

正Mg-Li合金是当今世界上最轻的金属结构材料,中国铝业郑州有色金属研究院下属的郑州轻研合金科技有限公司是中国最大的Mg-Li合金生产企业,拥有完整的、装备一流的Mg-Li合金熔铸、压力加工、切削加工、热处理及表面处理生产线,铸锭生产能力超过200 t/a,近十几年来,他们为中国电子科技集团、中国航天科工集团、中国兵器装备集团公司等单位提供了多种Mg-Li合金零部件的生产、加工及表面处理服务,为航空航天     

超轻质Mg-Li合金的研究现状

Mg-Li合金具有低密度、高的比强度和比模量,在宇航、汽车、电子等领域有广阔的应用前景,但是Mg-Li合金较低的高温力学性能限制了它的发展.介绍了Mg-Li系合金力学性能的研究现状及发展方向.     

Mg-Li合金的腐蚀机理与表面防护

Mg-Li合金作为目前最轻的金属结构材料,在航空航天、军事、电子产业等领域具有良好的发展前景.但较差的耐蚀性严重制约了Mg-Li合金的广泛应用,因此研究其腐蚀机理和表面防护极为重要.基于国内外的研究进展,综述了Mg-Li合金的腐蚀机理,系统总结了Mg-Li合金的表面防护方法,包括电镀、化学镀、化学转化、阳极氧化、涂层涂...     

Mg-Li合金的性能研究

根据Mg-Li二元合金相图设计了三种Li含量的Mg-Li合金。这三种合金分别具有α单相、α＋β共晶和β单相组织。对三种合金分别进行了拉伸、冲击试验和断口分析。结果表明：Mg-3．5Li（α相）合金有最高的抗拉强度和最低的塑性及韧性，拉伸和冲击断口主要呈脆性断裂特征；Mg-8Li（α＋β共晶）合金有最好的屈服强度、塑性和韧性，拉伸和冲击断口主要呈韧性断裂特征。     

镁-锂合金的性能与应用

Mg-Li合金是金属结构材料中最轻的一类合金,它在航空航天器中有重要的用途。对Mg-Li合金的组织性能、生产工艺作了全面的介绍。     

不同相组成Mg-Li二元合金的力学性能及阻尼性能

在氩气保护下采用电磁感应真空熔炼制备出单一α-Mg相、单一β-Li相及两相共存的3种不同相态的Mg-Li二元合金,并运用光学显微镜、XRD、阻尼测试及力学测试方法对合金的组织结构、力学性能及阻尼性能进行分析和讨论。结果表明:Li含量的增加使合金的相态发生改变,同时对合金起到晶粒细化的作用,且能有效地提高合金的屈服强度。体心立方结构的β-Li相会增大合金的临界应变振幅以及阻尼性能,但两相共存状态的Mg-Li合金具有最好的抗拉强度及伸长率。Mg-Li二元合金的新阻尼机制是由低温区域位错滑移、高温区域的晶界滑移以及合金中的晶格畸变这3种阻尼机制叠加而成。     

轻质金属的发展和应用：高强铝合金和镁合金

高强轻质合金在许多重要工程领域如汽车、海洋和航空航天应用占据重要的地位，Al/Mg-Li合金是最具代表性的高强轻质合金。Li的加入不仅减轻了铝/镁合金的质量，同时提高了强度和弹性模量。综述了最新的Al-Li和Mg-Li合金的微合金化、微观组织/缺陷以及先进的制造工艺和加工技术，旨在为未来轻质合金建立“成分-加工-微观结构-性能”的最佳组合提供参考。     

Rolling route for refining grains of super light Mg-Li alloys containing Sc and Be

Pioneering work on Sc or/and Be added Mg-Li alloys with refined grains was initiated.Various rolling-based thermo-mechanical treatments on these Mg-Li alloys were carried out.Four Mg-Li alloys were prepared by vacuum melting process.A unique route for producing fine grains was applied which concluded solution treatment at 350°C,cold rolling with 60% thickness reduction and 250°C annealing,successively.     

真空碳热还原制备Mg-Li合金热力学分析

提出了真空碳热还原制备Mg-Li合金的新思路,并对还原反应进行了热力学分析,研究了还原反应的反应式、吉布斯自由能及临界还原温度。结果表明:真空碳热还原制备Mg-Li合金具备热力学可行性,且其吉布斯自由能随真空度和反应温度的升高而降低;相同真空度下,该反应的临界反应温度低于真空碳热还原制备金属Mg、金属Li的临界温度,反应更容易进行;当真空度为10 Pa,Li_2O的相对比例为0.1时,真空碳热还原制备Mg-Li合金的临界反应温度为1345 K;在常规皮江法(真空硅热还原法)制镁的反应条件下,不论反应物料中Mg O、Li_2O相对比例为多少,真空碳热还原制备Mg-Li合金均具有热力学可行性。     

Electrochemical codeposition of typical α+β phases Mg-Li alloys from the molten LiCl-KCl-MgCl_2 system

Electrochemical codeposition of Mg-Li alloys on molybdenum electrodes was investigated in LiCl-KCl(50 wt.%:50 wt.%) melts containing different concentrations of MgCl2 at 973 K.Cyclic voltammograms show that the underpotential deposition of lithium on pre-deposited magnesium leads to the formation of liquid Mg-Li alloys.The deposition potentials of Mg(II) and Li(I) ions gradually near each other with MgCl2 concentration decreasing.Mg-Li alloys with typical α + β phases could be obtained by potentiostatic electrolysis from LiCl-KCl melts containing 5 wt.% MgCl2 at -2.25 V vs.Ag/AgCl(cathodic current density 1.70 A·cm-2) for 2.5 h.α phase, α + β phases, and β phase Mg-Li alloys with different lithium contents were obtained by potentiostatic electrolysis from LiCl-KCl melts with the different concentrations of MgCl2.The samples were characterized by X-ray diffraction and scanning electron microscopy.     

复合添加Y和Nd对Mg-Li合金显微组织及室温压缩织构的影响

采用OM,SEM,XRD,EBSD及电子万能试验机,对比研究了Mg-5Li-3Al-2Zn和Mg-5Li-3Al-2Zn-1.2Y-0.8Nd铸态合金的显微组织、力学性能以及室温单向压缩后的织构演变.研究发现,复合添加Y和Nd 2种稀土元素后,合金中絮丝状AlLi相明显减少,晶粒得到显著细化,平均尺寸在30μm左右.2种合金的塑性表现良好,加入少量稀土的合金室温压缩的变形量可达到27%.复合添加的稀士元素大幅度降低了Mg品格的c/a值,显著弱化了合金的基面织构,激活了锥面滑移系的同时,也使得室温下少见的柱面滑移破激活.     

Mg—Li—A1合金光学金相（OM）的研究

通过对LA141和LAZ933两种Mg—Li合金使用不同的腐蚀剂来制取金相，实验结果获得了制取Mg—Li合金金相的可行方法。对Mg—Li合金的研究提供了切实可行的辅助方法，解决了Mg—Li合金研究过程中的一大困难。     

Electrochemical codeposition of typical α＋β phases Mg-Li alloys from the molten LiCl-KCl-MgC2 system

Electrochemical codeposition of Mg-Li alloys on molybdenum electrodes was investigated in LiCl-KCl (50 wt.%:50 wt.%) melts containing different concentrations of MgCl₂ at 973 K. Cyclic voltammograms show that the underpotential deposition of lithium on pre-deposited magnesium leads to the formation of liquid Mg-Li alloys. The deposition potentials of Mg(II) and Li(I) ions gradually near each other with MgCl₂ concentration decreasing. Mg-Li alloys with typical α + β phases could be obtained by potentiostatic electrolysis from LiCl-KCl melts containing 5 wt.% MgCl₂ at −2.25 V vs. Ag/AgCl (cathodic current density 1.70 A·cm⁻²) for 2.5 h. α phase, α + β phases, and β phase Mg-Li alloys with different lithium contents were obtained by potentiostatic electrolysis from LiCl-KCl melts with the different concentrations of MgCl₂. The samples were characterized by X-ray diffraction and scanning electron microscopy.     

等通道转角挤压对Mg-Li合金力学性能的影响概述

等通道转角挤压（ECAP）是一种高效率的大塑性变形（SPD）技术,用于生产具有优异性能的超细晶粒（UFG）材料。本文总结了经ECAP加工的各种Mg-Li合金的力学性能、加工参数的影响及其相关机理,为未来提高镁锂合金力学性能提供研究方向与支持。     

Strengthening and Room Temperature Age-Softening of Super-Light Mg-Li Alloys

Extremely light (density ~1.46 g/cm³) and highly formable Mg-Li alloys have been drawing research interest; however, their relatively low strength is discouraging, and thus, an issue to be addressed. This paper processes and evaluates four Mg-Li alloys: the first, a basic alloy with a nominal composition of Mg-11%Li-1%Al-0.5%Zn; the second, an alloy with only Be added to the first; the third, an alloy with only Sc added to the first; and the fourth, with both Be and Sc added to the first. This research achieves a high strength of ~240 MPa for Mg-Li alloys using the processes of solid solution treatment plus 90% heavy rolling. A subsequent natural aging process proceeded spontaneously and resulted in strength decay. Room temperature softening behavior is uncommon, but offers a convenient route for studying age-softening characteristics of metallic alloys.     

Recent progress in Mg-Li matrix composites

Mg-Li matrix composites are one of the ideal structural materials in the fields of aerospace and military due to their high specific strength and stiffness, good damping and wear resistance, and small thermal expansion coefficient. The preparation technologies of Mg-Li matrix composites including powder metallurgy, pressure infiltration, stir-casting, foil metallurgy, and in-situ synthesis were introduced, and their advantages and disadvantages were compared. The common matrix alloys and reinforcements for Mg-Li matrix composites as well as the structure and performance of typical composites were mainly summarized. Then the interface chemistry between matrix and reinforcement was briefly reviewed. Finally, some problems existing at present and the possible solutions were discussed.     

Mg—Li合金性能改善的途径及发展方向

作为当今最轻的合金材料,Mg-Li合金日益受到广泛的关注。首先简述了Mg-Li=／9＂金的特点及应用,随后对Mg—Li合金的发展简史、国内外研究现状进行了介绍,在此基础上综述了Mg—Li合金性能改善的途径,主要包括合金化、晶粒细化、复合强化和表面处理等,最后分别就Mg—Li合金作为结构材料和新能源材料的发展方向进行了展望。