“泡沫铝”材料的性能特征及其在汽车工业的应用

作为新型结构功能材料的泡沫金属在力学、热学、声学、吸能等方面具有十分优异的性能。而"泡沫铝"是最具应用潜力的泡沫金属之一,被誉为"金属之星",已成为当前功能材料领域的研究热点。"泡沫铝"具有质轻、耐高温、抗腐蚀、不易燃、耐候性好、电磁屏蔽强、吸能降噪等系列优异性能,作为结构材料和功能材料广泛应用于工程技术领域。本文重点概述了泡沫铝的性能、制备工艺及其在汽车工业上的应用。     

泡沫铝材料的制备技术及其应用研究概述

简单介绍了泡沫铝材料的特性和发展进程,作为一种新型功能-结构金属复合材料,具有优异的综合性能和良好的应用前景。综述了泡沫铝材料的分类,分析了闭孔和开孔泡沫铝的制备方法和制备原理。并结合当前泡沫铝材料国内外最新研究进展以及在各个领域的应用情况,对未来研究发展的重点和趋势进行简要分析。     

泡沫铝及其复合材料的研究进展

泡沫金属是一种由金属基体和气孔组成的新型结构功能材料，相对于实体金属材料，泡沫金属材料以牺牲了强度等力学性能为代价，获得了诸如热、声、能量吸收、轻质等优越性能，成为一种新型结构功能材料。泡沫铝是一种在铝基体中形成很多气孔的轻质多孔金属材料，同时兼有金属和气泡特征，它密度小、耐高温、防火性能强、抗腐蚀、隔音降噪、导热率低、电磁屏蔽性高、耐候性强、有过滤能力、渗透性好，具有良好的阻尼特性和电磁屏蔽能力，广泛应用在冶金、化工、航空航天、船舶、电子、汽车制造和建筑业等领域。对泡沫铝制备方法和物理性能的研究有利于提高其性能、扩大其应用领域，本文概述了泡沫铝的制备方法、物理性能及增强泡沫铝基复合材料的研究进展。     

泡沫铝的连续制备

泡沫铝材是一种由气体和金属复合而成的新型材料,具有优异的综合性能,在各个领域有着广泛的应用前景.本文系统地阐述了采用二次发泡法连续制备泡沫铝的工艺过程和试验装置.     

含微小封闭空洞的泡沫铝

含微小封闭空洞的泡沫铝，它涉及一种含封闭型微孔的泡沫铝。该泡沫铝是在铝材料的基体内铸有空心体。该泡沫铝以空心体的空心作为泡沫金属的空孔，对基体的合金无选择，其孔隙率可达30％-60％。该含微小封闭空洞的泡沫铝具有高比强、阻尼减震、隔音、能量吸收等功能，并具有成本低、强度高、气孔大小易控制的优点。     

创意材料——泡沫铝

正泡沫铝是一种由铝或铝合金基体与气孔复合而成的新型轻质功能-结构一体化材料。这种特殊结构决定了其轻质性、高孔隙率、高比表面积等特点,由此获得许多致密金属所不具有的优良特性,如很强的能量吸收性、抗冲击性、高比强度、电磁屏蔽、吸声性能、高阻尼性、低热导率、低电导率等。泡沫铝的性能主要取决于孔隙率、孔径、通孔率、孔结构类型、比表面积等孔结构参数及金属基体。     

闭孔金属基复合泡沫材料制备技术研究进展

闭孔金属基复合泡沫材料是一种新型多孔复合材料,主要以空心微球和基体粉末为原料,将空心微球填充到金属或合金基体中复合而成;因其具有轻质、高强、良好的阻尼、吸能、隔热、隔音及电磁屏蔽等诸多优异性能,在减震、缓冲阻尼及防撞击等相关领域具有广泛的应用价值。本文主要介绍了利用空心微球制备闭孔金属基复合泡沫材料的方法,总结了其制备过程中存在的问题,并概述了闭孔金属基复合泡沫材料的应用。     

泡沫铝主要性能特征研究及工业应用

本文对新型功能材料泡沫铝的性能和工业应用作了介绍。当前泡沫铝的研究主要集中在力学、隔热、声学、电磁屏蔽等方面,并证明泡沫铝是优秀的动能吸收材料、散热阻燃材料、隔声降噪材料以及电磁屏蔽材料,因此泡沫铝可作为良好的新型材料在生产建设中广泛应用。     

泡沫铝主要特征性能研究

对新型的功能材料泡沫铝的性能和工业应用作了介绍,当前泡沫铝的研究主要集中在力学,隔热,声学,电磁屏蔽等方面,并证明泡沫铝是优秀的动能吸收材料,散热阻燃材料,隔声降噪材料以及电磁屏蔽材料,因此泡沫铝可作为良好的功能材料在生产建设中广泛应用;     

泡沫镍的电沉积法制备研究进展

泡沫镍作为一种新型的功能材料具有特殊结构和优异的性能,在燃料电池、电池电极材料、催化剂材料、过滤器、吸声材料等领域中都有广泛应用。本文介绍了泡沫镍的各种制备方法,重点对国内泡沫镍的电沉积法制备工艺进展进行了介绍。     

Blast Testing of Aluminum Foam–Protected Reinforced Concrete Slabs

Aluminum foam is a newly developed mobile and lightweight material with excellent energy absorption capacities. Applying aluminum foam as a sacrificial protection layer on the bearing faces of protected structures can mitigate blast effects on the resistance capacities of structures against impact or blast loading. The aluminum foam undergoes great plastic deformation under transient dynamic loads before becoming fully densified, making it excellent for mitigating blast effects on these structures. In this paper, we conducted quasi-static testing on two types of aluminum foam specimens and obtained the primary parameters for the mechanical properties of aluminum foam specimens. We then used these two types of aluminum foams to protect the reinforced concrete (RC) slabs, and we conducted a series of tests to investigate the performance of the aluminum foam–protected RC slabs against blast loads. We tested a total of five foam-protected slabs and one control RC slab in the blast test program. The test results, including displacement and acceleration histories, performance of specimens, and maximum and permanent deflections, were fully reported. We then discussed the efficiency of aluminum foam to mitigate blast loads on protected RC slabs.     

造孔剂法制备泡沫钛的研究现状与进展

泡沫钛融合了泡沫结构与金属钛的双重属性，具有出色的力学性能、优异的耐腐蚀性和良好的生物相容性等优点，在航空、航天、海洋工程、生物医学、能源与环保等领域应用前景广阔。基于粉末冶金技术的造孔剂法是目前制备泡沫钛的主流方法，不仅具有操作简单、设备要求低的优点，而且能通过调整造孔剂参数来控制最终制品的结构与性能。本文综述了造孔剂法制备泡沫钛领域的研究现状与进展，通过分析文献、整理数据，讨论了高孔隙率泡沫钛的研究历程和瓶颈问题，指出了泡沫钛孔隙率研究的发展趋势。     

Mechanical Testing and Finite Element Simulations for the Use of Cellular Metals as Car Seat Components

Due to the high energy absorption capacity at constant compressive stress level, cellular metals may be used as crash‐energy‐absorbing elements in autobody structures or car components, e.g., car seats. Modern car seats do not only have a high technical functionality, like electronic positioning, heating, and ventilation systems; in the case of a crash they must protect the passenger. The present paper deals with an analysis of potentially suitable cellular metals for integration in car seats. By means of different quasi‐static tests, i.e., compression, tensile, shear, and bending testing of several candidate metal foams and foam sandwich structures, the general material properties, the damage behavior and the reproducibility of mechanical data are tested. The results, which include optical 3D strain distribution measurements of the chosen cellular metals during quasi‐static testing, are implemented in the engineering design of structural car seat components and finite element calculations to simulate the crash behavior. Objective of the work is the derivation of robust and reliable mechanical testing procedures and standards as well as an improved understanding of the damage mechanisms of cellular metals under different loading conditions to finally derive design guidelines for cellular metals.     

Compressive Deformation Behavior of Highly Porous AA2014-Cenosphere Closed Cell Hybrid Foam Prepared Using CaH<Subscript>2</Subscript> as Foaming Agent: Comparison with Aluminum Foam and Syntactic Foam

Closed Cell AA2014-cenosphere hybrid foams have been prepared through stir-casting technique using varying amount of CaH₂ powder as foaming agent. The cenospheres in hybrid foams created micro-pores in the cell wall and in the plateau region. It reduced the requirement of CaH₂ for foaming by 30–40% by attaining equivalent level of relative density. These foams have been characterized for of microarchitechtural characteristics and mechanical properties like strength, densification strain and energy absorption. The properties of hybrid foams have been compared with those of conventional AA2014-SiC foam and Al-cenosphere syntactic foam. The closed cell AA2014-cenosphere hybrid foam exhibited comparable plateau stress, densification strain and energy absorption characteristics to those of AA2014-SiC foams with same relative density. Empirical relations to correlate plateau stress, densification strain and energy absorption for entire range of porosities have been established.     

Characteristics of aluminium metal foam for automotive applications

Closed cell aluminium foam has been examined with respect to crash protection systems, stiff and strong light weight structures and sound absorbing panels / enclosures for use in automotive systems. Monotonic compression tests revealed that the crash box made from aluminium foam-filled steel tube showed twice the energy absorption compared to empty crash box. Flexural studies on foam-filled thin walled aluminium extruded section showed higher resistance to bending (7.5 kN) against empty Al-section (5.8 kN). Differences in the mechanisms of deformation between foam filled sections and their empty counterparts were studied in compression and bend loading conditions. Acoustic behaviour was evaluated in the as-received foam and in foams post processed to increase cell interconnectivity. High sound absorption coefficients were observed in most conditions. The optimum combination of high sound absorption coefficient and frequency range occurred in a crushed foam with good cell interconnectivity.     

Mathematical Model to Estimate the Rate Parameters and Thermal Efficiency for the Reduction of Iron Ore–Coal Composite Pellets in Multi-layer Bed at Rotary Hearth Furnace

Aluminium foams have become popular because of their properties such as high stiffness combined with very low density. The aluminium foams are being used in many applications like automobiles, railways, aerospace, ship building, household applications etc. The development of foam with consistent quality and study of foam structure–property relation is important for both scientific and industrial applications. Metallic foams are commonly produced using hydride and carbonates foaming agents. However carbonate foaming agents are safer to handle than hydrides and produce aluminum foam with a fine, homogenous cell structure, low cost and easily available. The number of pores per inch and relative density of the foam play an important role on their physical and mechanical properties. Hence it is very important to investigate effect of grain size of calcium carbonate foaming agent on pores per inch and relative density. The present work deals with the effect of grain size of the calcium carbonate forming agent on the physical properties of an eutectic Al–Si alloy closed cell foam. The foam was produced with different grain size of calcium carbonate (150, 106, 75, 53 µm) as a foaming agent. The pores per inch and density of the foam produced with different grain size of calcium carbonates as foaming agent are determined. Relative density is in the range of 0.21–0.34, pores per inch is in the range of 11–20 for the produced eutectic Al–Si alloy closed cell foam. It is observed that as grain size of calcium carbonate used for production of aluminium foam increases, the number of pores per inch decreases, relative density decreases and porosity increases.     

Evaluation of mechanical properties of porous 6061 alloys fabricated by the powder compression and induction heating process

The purpose of this study is to evaluate the mechanical properties of 6061 Al foam products, which were fabricated by the powder compression and multistep induction heating method, and to build the database necessary for computer-aided modeling or foam components design. In this study, 6061 Al foams with various porosity fractions were fabricated according to the porosity fractions-final heating temperature curve. The relationships between porosity fraction and morphological properties (porosity diameter, number per unit area of porosities, and surface skin thickness) were investigated. Mechanical properties such as compressive strength, energy absorption capacity, and efficiency were investigated to evaluate the feasibility of foams as crash-energy-absorbing components. Furthermore, the effect of the surface skin thickness on the plateau stress and strain sensitivity of the 6061 Al foam with low porosities (pct) was studied.     

电沉积泡沫Ni-Mo合金

以聚氨酯泡沫树脂为基体,采用化学镀、电沉积、热解和氢气还原的方法制备出网状结构的泡沫Ni-Mo合金。对该泡沫合金的形貌、镀液组分与合金组分的关系和合金的抗拉强度、抗腐蚀性、高温抗氧化性进行了分析研究。试验结果表明:合金中Mo含量随着Na2MoO4浓度增加而增加,该泡沫合金骨架平整,泡沫Ni-Mo合金抗拉强度、耐腐蚀性和高温抗氧化性优于泡沫镍,在中性盐雾试验中的抗腐蚀性加强,高温抗氧化性也增强。