Recent Research and Development Activities on Mg Alloys at CAAM

A brief review of recent research and development activities on light weight Mg alloys at the Center for Advanced Aerospace Materials (CAAM) is reported. Current research projects include various fields such as: (i) development of high strength/ductility Mg alloys; (ii) improvement in corrosion resistant of Mg alloys; (iii) semisolid state processing of Mg alloys and (iv) development of ultralight Mg alloys. For commercial utilization of Mg alloy parts, several problems, such as melting/casting, corrosion and recycling, have to be tackled. This review also contains a brief summary of the development project of Mg alloy parts for commercial application, mainly for automobile parts.     

Designation and development of biomedical Ti alloys with finer biomechanical compatibility in long-term surgical implants

Developing the new titanium alloys with excellent biomechanical compatibility has been an important research direction of surgical implants materials. Present paper summarizes the international researches and developments of biomedical titanium alloys. Aiming at increasing the biomechanical compatibility, it also introduces the exploration and improvement of alloy designing, mechanical processing, microstructure and phase transformation, and finally outlines the directions for scientific research on the biomedical titanium alloys in the future.     

Metal Alloys for Fusion‐Based Additive Manufacturing

Metal additive manufacturing (AM) is an innovative manufacturing technique, which builds parts incrementally layer by layer. Thus, metal AM has inherent advantages in part complexity, time, and waste saving. However, due to its complex thermal cycle and rapid solidification during processing, the alloys well suit and commercially used for metal AM today are limited. Therefore, it is important to understand the alloying strategy and current progress with materials performance to consider alloy development for metal AM. This review presents the current range of alloys available for metal AM, including titanium, steel, nickel, aluminum, less common alloys (including Mg alloys, metal matrix composites alloys, and low melting point alloys), and compositionally complex alloys (including bulk metallic glasses and high entropy alloys) with a focus on the relationship between compositions, processing, microstructures, and properties of each alloy system. In addition, some promising alloy systems for metal AM are highlighted. Approaches for designing and optimizing new materials for metal AM have been summarized.

     

组合材料芯片技术在钛合金研究中的应用

综述了组合材料芯片技术在钛合金研究中应用的新进展.利用组合材料芯片技术在短周期内制备出合金元素梯度变化的多元钛合金样品,由于样品的加工状态和热处理条件相同,可以确定某种合金元素含量与整个钛合金体系组织和力学性能的定量关系.利用多种表征手段,从样品库中系统地分析组织和力学性能的变化规律并筛选出目标成分,显示出组合材料芯片技术在钛合金相变研究和合金设计中的优势.     

医用钛合金及其表面改性

目前钛合金被广泛应用于医学领域，如矫形用种植体。简要综述了新型医用钛合金的开发以及钛合金表面改性提高其表面生物活性和耐磨性能的研究进展。     

生物活性Ti合金材料的研究现状

Ti合金作为生物植入材料已应用于医学领域。综述了国内外Ti合金生物材料研究领域的最新进展，包括生物活性材料的微观特性、Ti合金表面改性和生物相容性。     

定向凝固钛铝合金熔体与铸型界面反应研究展望

钛铝合金是性能优异的高温合金,在航空航天领域有广泛的应用前景,但由于其熔体具有较高的活性,制备时熔体与所有已知的铸型材料会发生不同程度的反应,限制了钛铝合金铸件的发展.定向凝固技术作为制备高精度钛铝合金的新工艺,使铸件组织定向排列,可以进一步提高钛铝合金的使用性能,因此如何调控凝固过程中钛铝合金熔体与铸型材料间的界面反应成为目前有关定向凝固钛铝合金研究的一个热点.从目前国内外关于钛铝合金熔体与铸型材料间界面反应的研究出发,综述了定向凝固过程中铸型材料、涂层成分、工艺参数及合金元素等对界面反应的影响,介绍了界面反应的理论水平,系统收集了界面反应的各项研究结果.     

Challenges in alloy design: Titanium for the aerospace industry

This review describes the principles governing the design of titanium alloys for engine and airframe applications in the aeronautical industry. The relationships between processing, microstructure and properties of the commonly used α + β titanium alloys are described in some detail. The ‘state of science’ is seen to be sufficiently advanced to enable the metallurgist to optimally design this class of alloys to meet specific requirements. The challenges to the alloy designer lie in increasing the temperature capability of titanium alloys, and in standardising processing techniques which will decrease the high manufacturing costs of components.     

TA15钛合金与铝合金和结构钢接触腐蚀与防护研究

通过测定TA15钛合金与铝合金和结构钢组成的电偶对的电偶电流的方法,研究了TA15钛合金在使用中与铝合金和结构钢接触时产生电偶腐蚀的敏感性.结果表明:TA15钛合金与铝合金和30CrMnSiA钢接触时会产生严重的电偶腐蚀,必须进行防护处理方可使用;与30CrMnSiNi2A钢接触产生的电偶腐蚀比较轻微.对铝合金和结构钢进行表面处理可以降低电偶腐蚀敏感性,表面处理后喷涂底漆可进一步降低电偶腐蚀敏感性.     

钛合金表面耐磨涂层的研究现状及应用

耐磨性差是影响钛合金在航空航天领域广泛应用的因素之一,因此改善耐磨性成为钛合金改性研究的一个主要方向.系统地介绍了高硬度耐磨涂层、自润滑减摩涂层和耐磨复合涂层的研究及应用现状,并分类总结了钛合金耐磨涂层的组织结构及耐磨机理.分析结果表明:涂层中含有高硬度难熔耐磨相颗粒有助于提高表面耐磨性;含有硫化物等组分的涂层以自润滑减摩方式可减少磨损量;同时具有高硬度和低摩擦系数的复合涂层兼具上述两种性质,是钛合金耐磨涂层的发展方向之一.最后探讨了开发高性能耐磨表面涂层的相关问题.     

Some recent developments of advanced titanium alloy and nickel base superalloys in BIAM

A brief review of recent research and development works of some advanced Ti alloys and Ni base superalloys in the Institute of Aeronautical Materials, Beijing (BIAM) is reported. In which, the tensile deformation and fracture characteristics in an - Ti alloy, the creep behavior of Ti₃Al intermetallic alloy and effect of heat treatment and crystal orientation on the creep properties of a single crystal Ni base alloys DD3, are presented. The applications of the above mentioned alloys in aeronautic industry are described.     

The Status of the Aluminum Sheet and Plate Industries and Related Research Activities in Korea

This paper was prepared to review the status of the aluminum sheet and plate industries and related research activities in Korea. The aluminum sheets and plates which have been produced in Korea are mainly non-heat treatable alloys, so that the installations of the heat treatment facilities for producing the heat treatable sheets and plates are considered recently by aluminum industries in Korea. Concerning the research activities on the aluminum sheets and plates in Korea, the research topics and contents are mainly described on the basis of the highly advanced national projects which have been started since the middle of 1992.     

新型喷射成形轻质、高导热、低膨胀Si-Al电子封装材料

传统封装材料的性能已经不能满足微电子技术飞速发展的需要，为此，国内外相继采用喷射成形技术研究开发了适用于电子行业发展的新型Si-Al系列合金，这种高硅（50－70wt%)合金具有细小均匀的显微组织，以及均匀和各向同性的性能，同时具有低热膨胀系数，高热导率和低密度等特点，与普通碳化硅增强金属基复合材料（MMCs)不同，新合金可以用普通刀具进行加工，并且容易进行镀镍，铜、银和金等涂覆处理，采用上述材料已成功地制备了航空应用的微波放大器模块，比全可伐合金封装减重约30％以上，对喷射成形Si-Al合金的研究开发现状进行了简单评述。     

Effect of Equal Channel Angular Extrusion on the Microstructures and Properties of Two Extruded Al-Mg-Si Alloys

1.IntroductionAl-Mg-Si(6xxx)alloys make up nearly90%of alu-minium extrusion alloys[1].Chemical composition andheat treatment technique play important roles in gov-erning microstructure,extrudability and the mechani-cal properties of extrusions[2~12].A complete sequen-tial heat-treatment and thermo-mechanical processing(TMP)for6xxx series extrusion alloy is comprised ofhomogenisation,solution treatment,extrusion and age-ing.T5(see below)is a widely accepted post-extrusiontreatment in industry…     

Al-Ti异种合金真空钎焊的研究

在结合界面上生成层状的脆而硬的金属化合物（TiAl3,TiAl和Ti3Al)是Al-Ti异种合金焊接所存在的主要问题,本工作基一协内外研究成果和相关资料,利用正蛟设计在理,以Al-11.5Si近共晶合金为基,通过添加元素Sn和Ga形成9种钎料,并利用各新钎料对Al合金和Ti合金进行了真空钎焊,勇于强度试验和铺展性试验,对该9种钎料进行评定,试验结果表明,含10％Sn,0.20%GAa的Al-11.5Si铝基钎料铺展性和抗剪强度等方面都具有较好的性能,使Al-Ti异种合金构件达到较好的机械性能。     

钛合金深冷处理工艺研究综述

钛合金以其优异的生物相容性、出色的力学性能和抗腐蚀性而广泛应用于航空航天等领域。然而,现代工艺制备的钛合金存在延展性和耐疲劳性较差的问题,同时钛金属本身的耐磨性也较差,因此需要通过合适的后处理工艺来改善其力学性能。在这种背景下,深冷处理凭借其便捷、无污染、低成本及能显著改善金属材料组织和综合性能等优势,成为机械加工领域备受瞩目的研究方向。首先简要介绍了深冷处理的发展历程以及2种主要加工方法：液态法和气态法,同时概括了气态法的具体流程。其次重点综述了国内外深冷处理工艺对钛合金组织和织构的影响,分别从深冷时间、深冷温度与循环次数3个方面,归纳了深冷处理工艺对钛合金硬度和拉伸性能的影响以及深冷工艺的作用机理,并进一步探究了深冷处理工艺对钛合金制件摩擦磨损性能和耐疲劳性能的影响规律。最后介绍了深冷处理复合工艺方法,为基于深冷处理的加工工艺的发展提供有益参考和启示。     

近β马氏体钛合金中的β→ω相变

近β马氏体钛合金的典型热处理制度为固溶时效,该类钛合金在水冷条件下会发生β→ω相变,该相变属于无扩散型相变,相变的形核源于母相(111)晶面的弹性位移重组,而后续时效过程是扩散型相变,其中强化相α相的析出与ω相的体积分数和形貌密切相关。综述了β→ω相变的相变机理和几种典型近β马氏体钛合金中的β→ω相变特点,总结了水冷态近β马氏体钛合金的电子衍射花样的规律。     

生物医学钛合金的研究现状及发展趋势

本文在回顾生物医学钛合金发展历史的基础上 ,综述了国外近年来新开发的生物医学钛合金的组成及性能 ,提出了我国生物医学钛合金的发展方向。     

Effects of Alloying Elements on the Volume Fraction of Ordered α2 Phase Precipitated in Ti-Al-Sn-Zr Alloys

An ideal method has been established for calculating the precipitation of α2 ordered phase in near-α titanium alloys based on the theory on the critical electron concentration for the precipitation of α2 ordered phase in near-α titanium alloys. With complete precipitation of α2 phase in near-α titanium alloys, the alloys can be considered to be composed of two parts： （1） the α2 ordered phase with the stoichiometric atomic ratio of Ti3X; （2） the disorder solid solution with the critical composition in which the α2 ordered phase is just unable to precipitate. By using this method, the volume fractions of α2 ordered phase precipitated in Ti-Al, Ti-Sn, Ti-Al-Sn-Zr alloys with various AI, Sn and/or Zr contents have been calculated. The influences of AI and Sn on the precipitation of α2 ordered phase are discussed. The calculating results show substantial agreement with the experimental ones.     

我国创新研制的主要船用钛合金及其应用

钛及钛合金因优异的综合性能在航空、航天、舰船、化工等行业获得广泛应用,为满足不同的应用需求,近20年我国新型钛合金的研制非常活跃,其中舰船用钛合金是我国钛合金研究和发展的重要研究方向之一。经过近50多年的努力,我国创新研制的不同强度级别船用钛合金已基本形成体系,也制备出这些合金不同规格的管、板、棒、丝材等,已基本能够满足我国工程的需求。简要介绍了中国创新研制的主要船用钛合金及其应用,如中强高韧Ti75合金、中强高塑Ti31合金、高强高韧Ti-B19合金、中强Ti91和Ti70合金、高强Ti80合金等,同时也简要介绍了可能用于海洋工程的其他创新研制的钛合金,如高强(1 100 MPa)高韧损伤容限型TC21合金、中强(900 MPa)高韧损伤容限型TC4-DT合金、强度为1 300 MPa的Ti-1300、强度为1 500 MPa的Ti-1500、强度为1 600 MPa的Ti-1600合金以及中强的低温钛合金CT20等。