汽车车身用6000系铝合金板材微观组织与热处理工艺的研究进展

本文介绍了6000系铝合金在汽车车身上的应用现状及其性能特点,并详细论述了该系合金的时效析出特征、强化机理、织构演化和合金元素对性能的影响。此外,分析了6000系铝合金的传统热处理工艺,阐述了固溶后预时效和预变形对合金烘烤硬化性的影响,并探讨了汽车车身用6000系铝合金目前存在的问题及当前的主要研究方向。     

汽车车身板用变形铝合金研究进展

基于汽车轻量化的大背景,铝合金因其优异的综合性能成为汽车用板材的优选材料.主要综述了汽车车身板用变形铝合金的研究进展,以汽车车身板材常用的2×××、5×××、6×××和7×××系变形铝合金的应用现状为基础,结合国内外研究者现阶段的研究成果,对各系变形铝合金应用在汽车车身板中的优劣势展开了分析.在此基础上,着重介绍了各系...     

铝合金汽车板性能及其应用

深入讨论了预处理工艺的影响并说明了该工艺在保证铝合金汽车板使用性能的重要性。介绍了铝合金汽车板在汽车上的典型应用。基于笔者认识和目前的研究进展,提出了汽车用铝合金汽车板的重点研发内容,降低成本和价格,做好应用研究是扩大铝合金汽车板在汽车上应用的重要工作。     

汽车车身板用6A16铝合金拉深成形金属流动和微观组织相关性研究

由于能源和环境问题的日益严峻,汽车轻量化的研究和发展成为热点,其中6000系铝合金在汽车车身板上的应用受到广泛关注。本研究基于ABAQUS/Explicit有限元方法,对预时效并室温停放一周后的6A16铝合金板材在适宜条件下的拉深成形过程进行模拟,并通过试验进行验证。研究结果表明:Barlat91屈服准则适用于模拟6A16铝合金的拉深成形。在6A16铝合金的拉深成形过程中,铝合金板材顶部增厚,易产生褶皱;筒壁随着筒高的减小而减薄;圆角处最薄,易破裂;底部形变量少。经560℃/30 min的固溶处理+140℃/5min预时效处理后的6A16铝合金板材(T4P态)晶粒取向以Cube取向为主,随着拉深成形的进行,Cube取向晶粒逐渐消失,并在轧制方向和垂直轧制方向四个位置产生制耳。在本试验研究范围内,随着筒壁高度的增加,板材晶粒尺寸变大,小角度晶界比例增大,Mg_2Si和富Si相尺寸变小。     

7xxx系铝合金的研究现状及发展趋势

评述了国内外7xxx系铝合金的研究及工业应用概况,讨论了热处理工艺对7xxx系铝合金微观组织与性能的影响,介绍了相关的表征技术.针对目前7xxx系铝合金在研究以及产业化应用中存在的问题,指出实现7xxx系铝合金的高强、高韧以及低应力腐蚀(SCC)敏感性将成为今后研究和开发工作的主要方向,并提出了具体的建议.     

7xxx 系铝合金时效处理的研究现状及应用进展

简要分析了7xxx系列高强铝合金的时效强化机理,归纳了7xxx系铝合金的时效处理工艺,讨论了典型牌号7xxx铝合金的时效处理工艺及其在工业生产,特别是航空航天领域的应用情况,评述了7xxx铝合金时效处理的国内外研究现状.针对目前存在的问题并结合实践应用的要求,提出了未来7xxx系铝合金时效处理工艺研究和开发的重点.     

Cu对6000系和7000系铝合金时效过程中微结构演变的影响

介绍了几种研究铝合金时效过程中微结构演变的先进实验及模拟手段,包括用于显示原子列Z衬度的高角环形暗场-扫描透射电子显微术(HAADF-STEM)、分析微区中不同元素三维空间分布的三维原子探针技术(3DAP)、复杂选区电子衍射(SAED)模拟及第一性原理计算。综述了近年来作者及国内外学者使用这些手段研究Cu元素添加对6000系和7000系铝合金时效过程中微结构影响的进展,包括Cu添加对合金析出序列、时效析出速率、合金的析出硬化效果、析出物(如GP区、β″亚稳相、η平衡相等)的化学计量比及原子占位等的影响。最后展望了采用热力学、动力学计算及相场模拟等方法在铝合金设计中的应用,指明了通过对铝合金微结构进行定量模拟并结合关键实验验证来实现铝合金高效设计的发展方向。     

铝合金在汽车上的应用

摘甍作为未来汽车节能环保重要措施的汽车轻量化越来越多的受到研究者的关注,而铝合金作为轻量化材料也得到了很大的关注,本文通过介绍铝合金在汽车上的一些应用介绍。使铝合金材料得到更好的应用与发展,指出铝合金在汽车上应用的重要意义。     

铝合金在汽车工业中的应用现状及展望

随着大气污染和能源问题的日趋严峻,汽车轻量化是势在必行的。汽车制造工艺中应用的铝合金作为综合性能较好,质量较轻的金属材料,代替钢质零部件指日可待。文章介绍了应用铝合金制作汽车零部件的现状以及对铝合金在汽车工业中的展望。     

快速凝固铝硅合金材料及其在汽车中的应用

本文介绍了快速凝固技术的特点及在高硅铝合金中的应用潜力,综述了快速凝固高硅铝合金的制取方法及研究现状,扼要总结了快速凝固高硅铝合金在汽车工业中的应用,最后提出这一研究领域中存在的问题及发展前景。     

Cryogenic mechanical behavior of 5000- and 6000-series aluminum alloys: Issues on application to offshore plants

The mechanical behavior of aluminum alloys was investigated in terms of four aspects: temperature, strain rate, material type, and fracture shape. The candidate materials were 5000- and 6000-series alloys. The material characteristics were investigated and summarized as a function of low temperature (110–293 K) and quasi-static strain rate (10⁻⁴ and 10⁻² s⁻¹). The results confirmed that the strength and ductility of aluminum alloys improved with a decrease in the temperature. The aluminum alloys showed a strain rate effect only in terms of the ductility of the 5000-series alloys. In addition, fractography analyses were performed on the fracture specimens to explain the material behavior at cryogenic temperatures.     

铝合金激光表面改性技术研究进展

阐述了国内外铝合金激光表面改性技术的最新研究进展,重点介绍了激光表面重熔(LSM)、激光熔覆(LC)及激光表面合金化(LSA)3种表面激光改性方法和其对铝合金表面组织的影响及改性效果,总结了铝合金表面激光改性过程中存在的问题,并指出了今后努力的方向.     

Vakuumkomponenten für UHV und XHV aus Aluminium

Vacuum components of aluminum for UHV and XHV — mechanical strength The mechanical strength of 6000 series Al alloys is sufficient to generate stable CF knife edges. In order to preserve the mechanical strength it is vitally important that the maximum temperature of the material is not exceeded both during the production process and in the application. The suitability of these Al alloys in UHV and XHV applications is verified by measurements of the knife edge geometry.     

Research and Progress in Laser Welding of Wrought Aluminum Alloys. II. Metallurgical Microstructures, Defects, and Mechanical Properties

With the wide application of aluminum alloys in automotive, aerospace, and other industries, laser welding has become a critical joining technique for aluminum alloys. In this review, the research and progress in laser welding of wrought aluminum alloys are critically discussed from different perspectives. The primary objective of the review is to understand the influence of welding processes on joint quality and to build up the science base of laser welding for the reliable production of aluminum alloy joints. Two main types of industrial lasers, carbon dioxide (CO₂), and neodymium-doped yttrium aluminum garnet (Nd:YAG), are currently applied but special attention is paid to Nd:YAG laser welding of 5000 and 6000 series alloys in the keyhole (deep penetration) mode. In the preceding article of this review (part I), the laser welding processing parameters, including the laser-, process-, and material-related variables and their effects on welding quality, have been examined. In this part of the review, the metallurgical microstructures and main defects encountered in laser welding of aluminum alloys such as porosity, cracking, oxide inclusions, and loss of alloying elements are discussed from the point of view of mechanism of their formation, main influencing factors, and remedy measures. The main mechanical properties such as hardness, tensile and fatigue strength, and formability are also evaluated.     

Elaboration of aluminum-matrix composite materials reinforced with inorganic fibers

This article is a literature survey concerning the different methods presently known for producing fiber-reinforced aluminum-matrix composites. The elaboration problems are discussed in terms of wettability between aluminum or aluminum alloys and inorganic fibers. The fibers involved are continuous monofilaments about 100 μm diameter such as boron or silicon carbide fibers, and tows of 500–6000 endless thinner filaments 5–15 μm as graphite fibers, alumina fibers and Nicalon silicon carbide fibers. The typical mechanical properties (strength, modulus, fatigue) attained with these reinforcing fibers are also reported.     

Research and Progress in Laser Welding of Wrought Aluminum Alloys. I. Laser Welding Processes

With the wide application of Al alloys in automotive, aerospace and other industries, laser welding has become a critical joining technique for aluminum alloys. In this review, the research and progress in laser welding of wrought Al alloys have been critically discussed from different perspectives. The primary objective of this review is to understand the influence of welding processes on joint quality and to build up the science base of laser welding for the reliable production of Al alloy joints. Two main types of industrial lasers, carbon dioxide (CO₂) and neodymium-doped yttrium aluminum garnet (Nd:YAG), are currently applied but special attention is paid to Nd:YAG laser welding of 5000 and 6000 series alloys in the keyhole (deep penetration) mode. In this part of the review, the main laser welding processing parameters including the laser-, process-, and material-related variables and their effects on weld quality are examined. In part II of this article in this journal, the metallurgical microstructures and main defects encountered in laser welding of Al alloys such as porosity, cracking, oxide inclusions, and loss of alloying elements are discussed from the point of view of mechanism of their formation, main influencing factors, and remedy measures. In part II, the main mechanical properties such as hardness, tensile, and fatigue strength and formability are also discussed.     

Hot Sheet Metal Forming Strategies for High-Strength Aluminum Alloys: A Review—Fundamentals and Applications

In the past decade, aluminum alloys have become important structural materials in the automotive industry, thanks to their low density, high strength, high fracture toughness, and good fatigue performance. However, an important limitation of aluminum alloys is their poor formability at room temperature; as a result, numerous studies have been conducted with the aim of developing forming techniques to overcome this and facilitate the forming of more complex-shaped components. Following an overview on the metallurgical background of aluminum alloys, this article reviews recent developments in forming processes for aluminum alloys. The focus is on process variants at room temperature and at higher temperatures and on a new hot forming technique promising considerable improvements in formability. This review summarizes the influence of different process parameters on microstructures and mechanical properties. Particular emphasis is given to process design and to the underlying microstructural phenomena governing the strengthening mechanisms.     

Microstructure of Al-Mg-Si Weld Joints Produced by Pulse TIG Welding

Al-Mg-Si alloys (6000 series) are heat-treatable aluminum alloys and are extensively used in various sectors such as aerospace, automobiles, and general construction. Fabrication of these alloys often requires welding. Pulse TIG offers many advantages over conventional TIG welding as far as control of microstructure is concerned. This research investigated the effect of pulsed TIG welding parameters such as pulse duration, peak current, pulse frequency on the microstructure of heat-affected zone, and fusion line and weld metal of Al-0.5%Mg-0.5%Si weld joints. It was observed that a significant change in microstructure takes place in moving from the base metal to weld centerline. Dissolution of phases present along the grain boundary occurs as the fusion line is approached. Grain structure of heat-affected zone, fusion line, and weld metal appears to have tangible relationship with pulse parameters.     

Improved properties of A319 aluminum casting alloy modified with Zr

The beneficial effects of 0.15 wt.% Zr addition on mechanical properties and wear resistance of A319 aluminum casting alloy were investigated. The cast alloys were given a solutionizing treatment followed by artificial aging in the temperature range 175 to 235 °C for different period of times. Mechanical properties and wear behavior of the Zr-containing material were determined and compared to those of the base A319 alloy in both as-cast and age-hardened conditions. It is shown that minor addition of Zr results in the precipitation of Al₃Zr particles in the aluminum matrix. These particles are stable upon heating due to the low solubility of zirconium in aluminum matrix. The main effects of such particles are an increase in hardness, strength, quality index and wear resistance. This is very promising where these aluminum cast alloys are to be used at relatively high temperatures.     

激光选区熔化成形高强铝合金晶粒细化抑制裂纹研究现状EI北大核心CSCD

高强铝合金(2×××,7×××等)因具有比强度高、加工性好等优点而被航空航天、汽车等领域广泛应用。随着大推重比飞行器设计及汽车轻量化技术的发展,轻质结构材料的需求日益增加,同时零部件也面临着“薄壁化、中空化、复合化”的发展趋势,高强铝合金的传统加工方法越来越难以满足要求。近年来,激光选区熔化成形(selective laser melting,SLM)作为一种常见的金属增材制造技术(additive manufacturing,AM)在复杂零部件成形领域受到关注,有望成为进一步拓宽高强铝合金应用领域的新兴技术。然而,SLM成形高强铝合金因易产生周期性热裂纹和粗大柱状晶不良组织等问题而发展缓慢,晶粒细化是克服增材制造高强铝合金这一固有热裂问题的关键所在。本文综述了近年来SLM成形高强铝合金显微组织和力学性能调控等方面的研究进展,归纳了不同体系合金的力学性能,重点阐述了抑制SLM成形高强铝合金中热裂纹形成的主要策略,包括SLM工艺参数优化以及通过微合金化或添加纳米颗粒细化晶粒等方法。指出当前研究存在的主要问题是合金成分的改变对材料综合性能以及热处理制度的影响规律尚不清晰等,并展望了未来的发展趋势,如SLM成形新型高强铝合金成分设计与综合性能评价、利用后处理工艺等手段进一步提升合金综合性能以及专用晶粒细化剂的设计与细化机制探究等。