粉体发泡法制备泡沫金属的影响因素

介绍了粉体发泡法制备泡沫金属的生产工艺.从材料选择、预制品制备、发泡过程三个环节分析了在制备泡沫金属过程中可能出现的影响因素.最后对粉体发泡法生产泡沫金属的发展前景做了前瞻性展望.     

铸造法制备泡沫钢研究进展

介绍了熔体发泡法、渗流铸造法和Gasar法三种铸造方法制备泡沫金属的工艺原理以及国内外采用这几种方法制备泡沫钢的试探性研究和最新研究进展,阐述了三种制备方法的关键技术和难点,提出了突破相关技术屏障的建议.最后对铸造法制备泡沫钢的研究方向做了前瞻性的展望.     

熔体发泡法制备多孔泡沫钢发泡剂的研究

针对熔体发泡法制备多孔泡沫钢的发泡剂选取进行了研究,对选取的金属碳酸盐发泡剂和氮化物发泡剂进行了比较,分析了氮化物适合作为熔体发泡制备泡沫钢的发泡剂的原因,进一步对发泡剂氮化铬的分解动力学进行了分析,得出氮化铬更加适合于熔体法制备泡沫钢。     

泡沫铝的液相制备技术研究

多孔金属是近10年迅速发展起来的一种结构和功能一体化的新型工程材料.泡沫铝属于多孔金属中的一种,具有很好的环境功能特性,无毒、美观且可回收,应用前景广阔.泡沫铝的制备方法有很多,可分为液相法、固相法和沉积法三大类.详细介绍了泡沫铝的各种液相制备技术及生产研究现状,对制备技术中现存的一些问题作了简略概括.并提出了今后努力的方向.     

泡沫钛的制备和性能研究进展

近年来泡沫钛一直是泡沫金属研究中的热点之一。其主要的制备方法有粉末冶金法、浆料发泡法、捕获气体发生膨胀法、自蔓延高温合成法、气体-金属共晶凝固、快速成型法、纤维烧结法、等离子喷涂法、相变超塑性法、凝胶注模法、等离子体活化烧结法等,对其性能研究主要集中在结构参数、力学性能、耐腐蚀性能和生物相容性等方面。对泡沫钛的制备和性能进行了综述,并对今后的性能改良和理论模型研究等方向进行了展望。     

铸造法制备泡沫金属材料

泡沫金属是一种集力学性能、热电性能、声学等性能于一体的宏观结构一功能一体化的环保材料，由于其巨大的应用前景，在工业领域，特剐是汽车和航空航天领域受到了越来越广泛的重视。泡沫金属的制备方法很多，与其它制备方法相比，基于金属熔体的铸造法具有产量大、成本相对低廉、易于工业生产等优点，因而已被广泛研究并已部分实现了产业化。本文对当前应用于泡沫金属研究领域的几种铸造方法的工艺过程进行了详细介绍，并分析了其优缺点。     

电解液喷射沉积制备泡沫镍技术及其应用现状

介绍了电解液喷射沉积制备泡沫金属技术,说明了电解液喷射沉积法的原理及特点,综述了泡沫镍在电极材料、催化剂载体和超级电容器等方面的应用.     

铸造法泡沫铝制备工艺的研究及散热特性初探

针对国内对泡沫铝制备方法的研究中尚无采用熔模铸造法制备通孔泡沫铝的情况下,进行了本文的研究.在评述泡沫金属性能、用途及制造方法的基础上,本文选用熔模制造法来制备通孔泡沫铝.文章重点分析研究熔模铸造法泡沫铝的制备工艺,在预制型的制备上选用石膏作为耐火材料,同时石膏中加入添加剂与填料,并通过试验确定其配比关系.在吸铸工艺上确定其工艺参数,并成功地制备了通孔泡沫铝.在此基础上对高压渗流法泡沫铝的制备工艺进行了改进,采用溶剂粘结法制备盐预制型,确定溶剂与盐粒子的配比关系,利用真空渗流工艺代替高压渗流工艺制备泡沫铝,简化了制备工艺.文章对泡沫铝的散热性能进行分析、研究.指出泡沫铝具有良好的散热能力.并通过试验证明泡沫铝散热性能与孔隙结构的关系,得出泡沫铝散热性能具有强的结构敏感性.     

泡沫钛的制备技术及应用的研究现状

近年来,泡沫钛一直是泡沫金属研究中的热点之一。介绍了泡沫钛的主要制备方法:基于固态金属的制备方法,如粉末烧结法、粉体发泡法、浸浆烧结法、纤维烧结法、捕入气体压缩膨胀法、凝胶注模成型法、自蔓延高温合成法、快速成型法、等离子喷涂法、等离子体活化烧结法等;基于液态金属的制备方法,如铸造法(定向凝固法、自然凝固法、气体-金属共熔凝固法)。随着对泡沫钛研究的深入,发现泡沫钛具有密度低、比强度髙,抗腐蚀渗透性强、能量吸收性好,隔热、隔声效果好等特优异的性能,不仅在钛及钛合金的传统应用领域有良好的应用前景,也将在过滤与分离、流体分布与控制、防撞与防震、隔热与绝热、吸声降噪、多孔电极、生物植入体等领域拥有广阔的应用前景。     

泡沫铝的制备及其力学行为的研究

简要介绍泡沫金属的性能特点、制备方法及其应用.采用加压渗流法制备具有开孔结构的泡沫铝,并对此分别进行准静态和动态压缩实验,研究其静态和动态压缩应变力-应变响应特征、应变率效应和吸能特性.实践证明这种泡沫铝具有很明显的应变率效应.     

Fabrication of Al-Mg-Re foams and their corrosion resistance properties

Al-2 wt.% Mg-Re foams with relatively small pore size (∼1 mm) were fabricated by the melt foaming method with the addition of titanium hydride as a blowing agent. The corrosion resistance properties of the Al-Mg-Re foams have been studied and the results compared with those of Al foam and Al-5 wt.% Cu foam. The results show that in order to get Al-Mg-Re alloy foams with good pore structures, Ca and Mg should be added to the pure Al melt before adding the blowing agent; the corrosion resistance properties of Al-Mg-Re foams are better than those of Al foam and Al-Cu foams.     

穿孔法改进泡沫铝的吸声性能

利用熔体发泡技术制备不同孔径和气孔率的泡沫铝,对不同气孔率的原始状态泡沫铝以及孔径为1.1 mm的穿孔泡沫铝的吸声性能进行研究。结果表明:未设置背腔时,原始状态泡沫铝的吸声性能不高,设置背腔后,由于泡沫铝中所含通透结构的作用,泡沫铝的吸声性能明显提高;穿孔泡沫铝的穿孔率在0.5%～1.0%范围,设置60～80 mm背腔时可使降噪系数超过0.42,比原始状态泡沫铝不设置背腔时的降噪系数高2倍左右;穿孔泡沫铝设置背腔后的吸声特性符合Helmholtz共振吸声的规律,但受到穿孔结构、泡沫铝原本存在的缺陷组成的通透结构和气泡孔在穿孔过程中被打开的小开口等因素的影响。     

SiO2包覆CaCO3在无保护气氛下制备闭孔泡沫镁（英文）

在熔体发泡法工艺中,发泡剂的分解速度和浸润性直接影响泡沫金属的孔结构和孔隙率。为减缓泡沫镁发泡剂CaCO3的发泡速度并提高与镁熔体的浸润性,采用非均匀形核法,以硅酸钠为原料,盐酸为酸化剂,在CaCO3表面包覆SiO2钝化膜。采用TGA-DTA、XRD、SEM等方法对包覆后CaCO3的热稳定性和包覆层的微观结构进行分析。结果表明:包覆后的CaCO3分解温度提高;包覆层中的SiO2为无定形态;在CaCO3颗粒表面形成网络状结构。对比实验表明:包覆后的CaCO3发泡速度平稳。同时,采用合金化阻燃工艺在无气体保护条件下制备出较大尺寸的泡沫镁试样,并且试样孔径细小,孔结构均匀,孔隙率在60%-70%。     

Compressive behavior of SiCp/AlSi9Mg composite foams

Closed-cell AlSi₉Mg foams and SiC_p/AlSi₉Mg composite foams with different SiC_p volume fractions were prepared successfully by means of direct foaming of melt using CaCO₃ blowing agent in this paper. The compressive behaviors of these foams were studied. In comparison with the compressive stress–strain curve of AlSi₉Mg foams that of SiC_p/AlSi₉Mg composite foams is not smooth and exhibits some serrations. At the same relative density of composite foams, the yield stress and collapse stress of the composite foams increase with increasing SiC_p volume fraction. The relationship of yield stress, relative density and SiC_p volume fraction of SiC_p/AlSi₉Mg composite foams with a given particle size was obtained.     

吹气法制备泡沫铝的性能

基于吹气法制备A356基泡沫铝工艺,采用高速搅拌并分批连续加入粉末的方式,避免熔体中颗粒分布不均匀的问题;采用静置吹气头通入压缩空气发泡,通过设计和控制气路,制备出不同孔径、不同壁厚、稳定的泡沫铝.结果表明A356基泡沫铝是一种典型的塑性泡沫材料,泡孔呈十四面体形状,泡壁较薄,厚度小于150μm,可控的泡孔平均直径范围很宽,为10～25mm;泡沫铝在致密化阶段的塑性变形量可达70%以上;不作任何预处理的泡沫铝在高频率声波下的吸声系数可达0.9以上;在泡沫样品后设置0～70mm空腔,其在低频率声波下的吸声性能显著提高;所制备的泡沫铝具有较好的声学性能和力学性能.     

泡沫金属电阻率的计算方法

泡沫金属的孔率是一项易于测知和易于在制备过程中进行控制的特性指标,而其电阻摔在这两方面都比较困难。本文通过建立新的针对性理论公式,并与有关计算公式一起进行应用分析,找到了较合适的用孔率计算高孔率泡沫金属电阻率的方法,从而为多孔金属材料的整体优化和高孔率泡沫金属生产过程中电阻率指标的控制提供便利。     

Compressive properties and energy absorption of aluminum foams with modified cellular geometry

This study presents experimental results on the behavior of aluminum alloy metal foams with controlled pore morphology in compression. Two types of metal foams were analyzed, having uniform cell structure and with a dual-size cell arrangement seeking optimized mechanical properties. The structures were manufactured by lost-wax casting using 3D printed components for internal structure definition. Results for stiffness and energy absorption were obtained and compared on weight efficiency basis. The results are indicative of higher efficiency of the dual-size structures that may be considered for use in components subjected to impact or compression loading.     

Influence of Cell Shape Anisotropy on the Compressive Property of Closed-Cell Al-Si Alloy Foam

Closed-cell Al-Si alloy foams have been prepared by melt route. The cell shape anisotropy ratio of Al-Si alloy foams specimens in relative density range of 0.11-0.39 were measured. The quasi-static compressive tests show that Al-Si alloy foams have higher plastic collapse stress in the longitudinal direction (LD) than in the transverse direction (TD). The plastic collapse stress ratio increases with cell shape anisotropy ratio, which is basically in agreement with Gibson and Ashby model. Moreover, energy absorption capacity of Al-Si alloy foams was investigated. The results show that the energy absorption capacity in the LD is higher than that in the TD.     

Joining stainless steel metal foams

Abstract

Metallic foams produced from stainless steel are one of the most recently developed ultralightweight materials. These foams have very low densities and high energy absorption capacities and are therefore expected to have widespread applications in the manufacture of ultralightweight structural components. The fabrication of load bearing structural components such as implants, and high temperature air or fluid filters, are potential application areas depending on the form of the cell structure of the foam. Closed cell metal foams are typically suitable for structural uses whereas open cell foams tend to be preferred for functional applications. Development of adequate joining technologies for these materials is an essential step for their widespread industrial utilisation. The present paper describes a brazing method that is capable of providing excellent joints between 316 stainless steel foams and a conventional 316 stainless steel bulk alloy. Having optimised the bonding conditions and using a Cu–Ti alloy as the filler metal, bonds between a foam and a bulk alloy were produced. No apparent plastic deformation of the metal foam occurred in the course of the 10 min length brazing process, and the resulting bonds had tensile strengths higher than that of the stainless steel foam.     

Research Progress on Simulation Modeling of Metal Foams

对目前较为常用的6种泡沫金属的计算机仿真模型进行了概述和分析。这6种模型包括：立方胞模型,Gibson-Ashby模型,八面体模型,十四面体模型,Voronoi模型和三维随机球模型。不仅对每一种模型的结构进行了描述,而且对各种仿真模型在应用研究中存在的优缺点进行了综合分析。