金属增材制造技术的关键因素及发展方向

金属增材制造技术是一种短流程、近终形的新型材料成形技术.在金属增材制造技术中, 设备是载体, 材料是关键, 工艺是基础, 三者是影响金属增材制造技术发展的关键因素.本文通过对具有代表性的金属增材制造技术的特点进行总结, 分析了设备、材料和工艺之间的关系以及三者在金属增材制造技术中的重要作用; 综述了金属增材制造设备的原料供给系统、成形系统和控制系统的研究现状; 总结了金属增材制造材料中钛合金、镍合金、铝合金和钢铁材料的典型组织特点和力学性能; 论述了金属增材制造工艺参数对残余应力、孔洞、精度和组织的影响; 指出了目前金属增材制造技术在设备方面存在设备成本高、产品成形尺寸受限、成形效率低等问题, 在材料方面存在生产成本高、适用性差等问题, 在工艺方面存在参数匹配困难、热积累严重等问题; 从降低设备和材料成本、扩大产品成形尺寸范围、提高产品精度和成形效率、拓展材料种类和适用范围、减少工艺参数匹配难度、提升产品质量及综合性能、开发金属增材制造新技术方面展望了金属增材制造技术的发展方向.      

金属增材制造技术在核工业领域的应用与发展

增材制造能够制备任意复杂形状的零件,具有快速、高效、经济、全智能化和全柔性化制造的优势.本文总结了国内外典型的金属增材制造技术,介绍了金属增材制造技术在核工业领域的应用,梳理了增材制造核材料产品的性能表现,并以实际案例证明了金属增材制造技术在核工业领域的优势.本文结合革新性反应堆技术在核材料中的应用背景,展望了增材制造...     

金属增材制造技术研究热点聚类分析

为深入分析金属增材制造技术分类和发展状况,采集中国期刊全文数据库(CNKI)收录的核心期刊上的768篇科技文献,借助文献分析可视化软件CiteSpace,对关键词聚类进行了全景式描绘,构建金属增材制造技术知识图谱,揭示该技术研究分类以及演化趋势。     

面向野外装备应急维修的金属增材制造技术

金属增材制造技术具有利用率高、柔性高及快速性等特点,如果将其用于野外装备应急维修,将能有效克服传统装备应急维修方法的缺陷,提升野外装备的应急保障能力。本文对常见金属增材制造技术的成形效率、成形精度、力学性能进行对比,结合金属增材制造技术在国内外装备维修领域的应用现状以及野外装备应急维修的特点,从成形质量、成形能力、设备机动性以及抗干扰能力等几个方面展开分析,得出激光熔覆沉积以及电弧熔丝技术更适用于野外装备应急维修。最后就激光熔覆沉积以及电弧熔丝技术应用于野外装备应急维修亟待解决的问题以及今后发展趋势展开讨论。     

金属增材制造用钛粉制备研究

金属增材制造技术正朝着产业化的方向发展,钛粉是金属增材制造领域的主流原料之一。本文概述了钛及钛合金的熔炼技术,重点介绍了感应熔炼,并对目前主流的钛粉制备技术进行了对比和分析,包括基本原理、优缺点和影响粉末特性的因素等。此外,还介绍了数值模拟在钛粉制备上的应用,并对钛粉制备工艺在金属增材制造领域的发展做出了展望。     

美国科研人员探索如何减少金属增材制造制品中的缺陷北大核心

美国劳伦斯利福摩尔国家实验室与斯坦福直线加速器中心的研究人员开展合作,对使用同步加速器产生的X射线照射金属增材制造制品形成的图谱进行计算机模拟,找到了一种减少重要的金属增材制造零件缺陷的办法。劳伦斯利福摩尔国家实验室的研究人员Aiden Martin表示:根据观察发现在很多打印件的末端,也就是处于扫描激光器转向的位置,存在高密度的孔洞,影响了材料的性能。     

欧洲粉末冶金协会举办首个网络研讨会北大核心

欧洲粉末冶金协会与欧洲金属增材制造部门小组举办了2020年首个可以免费参加的粉末冶金教育性质的网络研讨会,这期研讨会的主题是金属增材制造,约有250人注册参加这次会议。欧洲粉末冶金协会技术主任Kenan Boz在会上表示:相信网络研讨会是欧洲粉末冶金协会促进粉末冶金各领域加深认识和理解的有力工具,并对欧洲粉末冶金协会举办的首个网络研讨会很受欢迎感到欣慰。     

金属增材制造数值模拟研究进展

作为高性能复杂金属构件的新兴制造技术,增材制造已被应用于航空航天、汽车工业、医疗和核电等领域.金属增材制造工艺涉及传热、热力、相变及流动等复杂物理现象,不同尺度及跨尺度数值模拟结合实验验证可实现对增材制造过程中复杂物理现象的理解、调控及优化,为高质量、高精度、高性能金属构件的成形提供有力支撑.本文综述了宏观、介观、微观...     

金属增材制造技术在航空领域的应用现状及前景展望

增材制造技术与传统铸造、锻造等方式相比,具有成形时间短、成形精度高、设计更自由等优势,是材料加工领域中最具有应用前景的技术之一,金属增材制造技术已在航空领域中得到广泛研究和应用。本文从技术原理、研究现状、航空应用等方面介绍了5种主要的金属增材制造技术,对比分析了国内外金属增材制造技术在航空领域中的研究和应用现状,阐述了增材制造技术对航空领域发展的重要性,并对金属增材制造的发展前景做出展望。     

金属材料3D打印领域创立《金属增材制造》期刊

<正>在2014年5月成功推出《金属增材制造》网站(http://www.metal-am.com)之后,2015年4月Inovar通信有限公司将出版发行一个新的面向金属增材制造领域的学术刊物——《金属增材制造》,《金属增材制造》期刊将以印刷版(ISSN 2057-3014)和数字版(ISSN 2055-7183)公开发行,报道金属增材制造领域的新闻,以及有     

高温合金材料在铝电解工业中的应用探讨

对高温合金在铝电解工业用作惰性金属阳极材料的选择进行阐述，并就实际应用过程中的抗氧化耐腐蚀性进行探讨；阐述适用于铝电解工业的惰性阳极合金所应具备的必要条件和必须解决的问题，并介绍目前有关的研究动态和研究方向。     

氩气雾化镍基粉末高温合金及粉末特性研究进展

概述了国内外镍基粉末高温合金的发展、氩气雾化制粉技术的特点、氩气雾化镍基高温合金粉末的特性和增材制造用镍基高温合金粉末的发展方向，重点介绍了镍基高温合金粉末的形貌与粒度控制、氧化特性、气体脱附行为和缺陷形成及控制措施。讨论了镍基高温合金粉末特性与合金缺陷之间的内在关系，总结了缺陷消除措施的研究进展，明确了未来粉末涡轮盘用氩气雾化镍基高温合金粉末质量优化的发展方向，并对高品质氩气雾化镍基高温合金粉末促进增材制造技术在航空航天领域的应用进行了展望。     

Additive Manufacturing of Single-Crystal Superalloy CMSX-4 Through Scanning Laser Epitaxy: Computational Modeling,Experimental Process Development,and Process Parameter Optimization

This paper focuses on additive manufacturing (AM) of single-crystal (SX) nickel-based superalloy CMSX-4 through scanning laser epitaxy (SLE). SLE, a powder bed fusion-based AM process was explored for the purpose of producing crack-free, dense deposits of CMSX-4 on top of similar chemistry investment-cast substrates. Optical microscopy and scanning electron microscopy (SEM) investigations revealed the presence of dendritic microstructures that consisted of fine γ′ precipitates within the γ matrix in the deposit region. Computational fluid dynamics (CFD)-based process modeling, statistical design of experiments (DoE), and microstructural characterization techniques were combined to produce metallurgically bonded single-crystal deposits of more than 500 μm height in a single pass along the entire length of the substrate. A customized quantitative metallography based image analysis technique was employed for automatic extraction of various deposit quality metrics from the digital cross-sectional micrographs. The processing parameters were varied, and optimal processing windows were identified to obtain good quality deposits. The results reported here represent one of the few successes obtained in producing single-crystal epitaxial deposits through a powder bed fusion-based metal AM process and thus demonstrate the potential of SLE to repair and manufacture single-crystal hot section components of gas turbine systems from nickel-based superalloy powders.     

Preparation, Structure and Mechanical Properties of Nickel Based Porous Spherical Superalioy

The porous superalloy materials with hollow spherical pores were fabricated by using metal powder sintering process. The scanning electron microscope (SEM) observation was applied to the test samples and it revealed that the pores of the porous material exhibited a uniform distribution and the apertures were of same size in principle. The sintering necks appeared between adjacent particles on metal skeleton after sintering. The mechanical properties of the test samples were analyzed and the result showed that this kind of materials possessed excellent energy absorption capability, and the compression resistance decreased with increasing the porosity and aperture.     

Preparation, Structure and Mechanical Properties of Nickel Based Porous Spherical Superalloy

 The porous superalloy materials with hollow spherical pores were fabricated by using metal powder sintering process. The scanning electron microscope (SEM) observation was applied to the test samples and it revealed that the pores of the porous material exhibited a uniform distribution and the apertures were of same size in principle. The sintering necks appeared between adjacent particles on metal skeleton after sintering. The mechanical properties of the test samples were analyzed and the result showed that this kind of materials possessed excellent energy absorption capability, and the compression resistance decreased with increasing the porosity and aperture.     

热加工对铸造AM50镁合金显微结构和力学性能的影响

采用锻造和等通道转角挤压(ECAP)等技术研究了热加工对铸造AM50镁合金显微结构和力学性能的影响, 以改善该合金的力学性能.结果发现, ECAP对铸造AM50镁合金和锻造AM50镁合金两种显微结构的影响不同, 这是由于两种状态初始晶粒尺寸不同引起的.铸态AM50镁合金晶粒尺寸粗大, 经过ECAP工艺后, 晶界上出现大量平直滑移线;而锻态AM50镁合金经过ECAP工艺后, 晶粒进一步细化, 滑移线痕迹不明显.铸态AM50镁合金经过ECAP工艺后显微硬度从54.5提高到72.3, 锻造AM50镁合金经过ECAP工艺后显微硬度从60.3提高到81.9.铸造AM50镁合金经过锻造及ECAP工艺热加工后力学性能抗拉强度提高到320 Mpa, 同时延伸率保持在35%以上.     

Directed Energy Deposition of Low-Alloyed Steels: An Insight on Microstructural and Mechanical Properties

Low-alloyed steels are used for a variety of different applications like bearings or gears. Additive manufacturing technologies like directed energy deposition (DED-LB/M) allow for a fast and close-to-contour fabrication of sophisticated products without excessive waste of material. However, the DED-LB/M process cannot be considered as state-of-the-art for this group of materials. This study presents findings on the material properties of the additively manufactured low-alloyed steel Bainidur AM by means of DED-LB/M. This includes studies on the mechanical properties (hardness, compression strength) as well as the microstructural properties (scanning electron microscopy [SEM]). The microstructure in the as-built state appears like a bainitic–martensitic one with shares of retained austenite which is not fully transformed during cooling. As a differentiation is barely possible from the SEM images, a plethora of investigations is further used to assess the microstructure. As-built samples possess a good combination of ductility and hardness. Furthermore, the specimens are characterized by a good tempering stability up to 600 °C. This tempering stability is characterized by a homogeneous hardness of around 400 HV1 for all temperatures. In contrast, the conventionally hardened specimens show a drop-off in material hardness, further indicating the excellent material properties of additively manufactured Bainidur AM.     

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.     

2013年云南冶金年评

依据2013年云南冶金科技工作者发表的文献资料,对该年度云南黑色金属冶金、有色金属冶金、半金属及稀有金属冶金和贵金属生产、科研及技术进行了评述.     

2012年云南冶金年评

依据2012年云南冶金科技工作者发表的文献资料,对该年度云南黑色金属冶金、有色金属冶金、半金属及稀有金属冶金和贵金属生产、科研及技术进行了评述。