江西省研制出泡沫金属材料

由江西省科技厅主持召开的“泡沫金属材料新工艺研究项目”鉴定会日前在鹰潭市拉下了帷幕,十一名国内知名专家一致认为,湿式电化学法生产泡     

新品开发

江西省研制出泡沫金属材料由江西省科技厅主持召开的″泡沫金属材料新艺研究项目″鉴定会日前在鹰潭市拉下了帷幕,十名国内知名专家一致认为,湿式电化学法生产泡金属是一项创新,在国内处于领先水平,市场前景阔,建议应尽快实现产业化。ZHEJIANGHUAGONG泡沫金属材料属于新材料科学的一个分支,可广泛应用于航空航天、汽车制造、化工、建筑、以及军工等领域,用作吸能器、消声器、减震器及催化剂等。鹰潭市的江西恒润实业公司,自2000年承担这一省级重点新产品研制任务后,历时两年多,终于完成了这一研究课题。与会专家认为,新工艺改传统的…     

论泡沫铝合金材料的渗流铸造成型

随着科学技术的进步,泡沫金属渗流铸造方面取得了一定的成绩,泡沫金属作为新型多空金属材料的一种,其结构于普通的金属材料有一定的不同,泡沫铝合金材料作为其中一种重要的组成部分,其与生活中的实体金属相比,有很多特殊的功能,现阶段很多航空材料,如飞机的零件等,还可以应用于生活中的一些噪音的降低、震动程度的降低等,这些都是泡沫金属在日常生活中的应用。本文首先对泡沫铝合金材料的渗流铸造的概况进行了简要的分析,然后分析了影响泡沫铝合金材料的渗流铸造成型的一些因素,并针对这些影响因素提出来一些完善泡沫铝合金材料的渗流铸造工艺的对策,希望对之后的泡沫铝合金材料的渗流铸造成型工艺的研究和改进有一定的促进作用。     

泡沫金属的隔热性能怒甩传统金属几条街

正近日,来自北卡罗来纳州立大学的研究人员制备出一种新型复合泡沫金属材料,其隔热性能远优于传统金属合金材料,在危险品存储运输和空间探测等领域有着广泛的应用前景,相关研究成果发表在期刊International Journal of Thermal Sciences上。复合泡沫金属材料凭借其优异的抗高速冲击性能及屏蔽辐射性能近来受到广泛关注。最近,北卡罗来纳州立大学机械与航天工程系教授Afsaneh Rabiei带领的研究团队发现,它的隔热性能也非常优异,在核材料及危险品的存储运     

多孔金属材料的制备研究进展

多孔金属材料兼具结构和功能材料的特点,在民用、工业、交通、军事、航空航天及环保等领域呈现出广阔的应用前景.在总结国内外科研成果的基础上,综述了现阶段多孔金属材料的常用制备方法(如铸造法、烧结法、金属沉积法、气体注入法等)研究进展,并对多孔金属材料的发展趋势进行了展望.     

复合型导电高分子泡沫的研究进展

综述了以热固性高分子和热塑性高分子为基体的复合型导电泡沫的制备方法,主要包括化学发泡法、物理发泡法和导电填料浸渍泡沫法等。总结了复合型导电高分子泡沫对温度等外场的响应行为,并对材料的应用前景进行了展望。     

酚醛泡沫成型技术研究进展

综述了酚醛泡沫成型技术的国内外研究进展,重点介绍了模压发泡法、浇注发泡法、喷涂法等几种主要酚醛泡沫成型方法,并对酚醛泡沫成型的发展趋势及应用前景进行了展望。     

碳纤维增强复合材料在汽车副车架中的应用

采用碳纤维布、聚对苯二甲酸乙二酯(PET)泡沫和阻燃环氧树脂,经真空辅助成型工艺制备了碳纤维泡沫夹芯复合材料。利用碳纤维泡沫夹芯复合材料代替原有的金属材料,采用真空导入工艺制作汽车副车架,为考虑承重及安装方便,设计了边梁、主梁和横梁的制作及搭接工艺。结果表明,采用此工艺大大减轻了汽车副车架的质量,整个副车架的总重仅为116 kg。     

Cl~-对泡沫镍制备工艺的影响

通过对比实验,研究了在制备泡沫镍材料的电沉积过程中Cl-对电镀阴极和阳极极化曲线、电沉积结晶形态以及电流效率的影响。提出在制备泡沫镍材料的工艺过程中,Cl-的质量浓度为10～15g/L时,能得到结晶致密、晶粒尺寸均匀的高性能金属材料,并且有利于提高阴极电流效率,节约生产成本。     

三维导热高分子复合材料制备方法研究进展

分析了构筑三维导热网络结构在导热高分子复合材料上的应用优势,介绍了构筑三维导热网络结构的不同方法,包括冻干取向法、金属泡沫法、陶瓷泡沫法、3D打印法、静电植绒法、静电纺丝法、碳泡沫法等,概述了不同构筑方法的成型机理,并对不同方法制备的三维导热高分子复合材料的热导率进行了归纳和总结.分析表明,构筑三维导热网络结构对高分子...     

Schaum und Schaumzerstörung – ein Überblick

Foam and Foam Breaking – A Review. Many technical processes produce foams which complicate the performance of a given process or even make it possible. Foam breaking, therefore, becomes necessary. This paper outlines well known and new methods of foam breaking as well as the breaking principles. For the example of sprinkling, the influence of selected parameters on the destruction efficiency and the formation of secondary foam can be demonstrated. After a discussion the properties of foam, stabilizing and destabilizing effects, possibilities of foam characterization and foam avoidance are presented.     

泡沫分离技术及其发展现状

探讨了泡沫分离技术的原理、泡沫分离设备及泡沫分离技术的研究进展。泡沫分离过程的性能受很多因素的影响 ,例如 ,进料液浓度、气泡尺寸、气体流量、泡沫的排液、进料位置、聚并、温度等。阐述了现有的几种新技术 ,如低重力条件操作、通过压力梯度而提高分离效率。此外 ,还简要介绍了泡沫分离塔中传质单元数和传质单元高度的概念。     

壳聚糖避孕泡沫气雾剂处方筛选研制

目的：制备避孕泡沫气雾剂,方法：以壳聚糖为基质制备避孕泡沫气雾。采用正交设计试验,以样品的黏稠度、泡沫细腻度及pH为考察指标,优化处方配比。结果：所制制剂为淡黄色半流体,产品质量符合《中国药典》2010年版气雾剂通则项下的要求。壳聚糖避孕泡沫气雾中壳聚糖、辛苯醇醚、甘油、柠檬酸的最佳用量分别为1．5％、3％、8％、2．0％。结论：壳聚糖避孕泡沫气雾的制备工艺简单、可行,杀精作用明显。     

泡沫分离设备的研究进展

作为一种新型分离技术,泡沫分离技术具有设备简单、能耗低、易于操作、低浓度条件下效率高和无污染等优点,该技术在降低表面活性物质分离成本方面具有极大的潜力,在工业上得到了广泛的应用。本工作分析了近年来文献报道中应用于分离回收蛋白质、有机污染物、天然产物、金属离子、微藻等的各种泡沫分离设备,并结合泡沫分离技术的发展历程将其分为传统泡沫分离设备和改进泡沫分离设备。重点阐述了改进泡沫分离设备的作用机理和分离效果,突显泡沫分离技术的重要性。改进型泡沫分离设备在一定程度上提高了分离效果,但依然存在一些问题,如很多设备在提高富集比的同时也降低了回收率。     

Schaumstabilisierung und Schauminhibierung

Foam Stabilization and Foam Inhibition After a general review on the field of foam stabilization and foam inhibition in the sector of washing, rinsing and cleansing agents, the recent developments in the field of foam inhibition are treated. According to these recently acquired knowledges, it is possible to regulate the foam formation by varying the temperature, however, independent of the hardness of water. Besides the chemical natures also the mechanisms of foam stabilization and foam inhibition are dealt with.     

Gas‐phase flow resistance of metal foams: Experiments and modeling

Based on experimental results of gas flow resistance through two metal foams, NC 2733 and Ni 2733, a modeling is performed to adjudicate governing flow mechanism. Two essential models are considered: developing laminar flow within short capillary channel (i.e., foam pore) and flow around solid body (foam strut modeled as cylinder or sphere), each of them of some variants. Foam geometry was studied using computer microtomography. The model of flow around a sphere (diameter equal to strut thickness) gives the best conformity with experiments. © 2017 American Institute of Chemical Engineers AIChE J, 63: 1799–1803, 2017     

Aluminum foam sandwich with adhesive bonding: Computational modeling

A numerical approach to simulate the delamination effect occurring in metal foam composites is being presented in this work. It is shown that in order to create reliable numerical models to simulate general components produced with aluminum metal foam sandwiches, the delamination effect of the aluminum skins from the metal foam must be considered. Delamination occurs within the polyurethane adhesive layer, causing the loss of the structural integrity of the structure. Foam is not a continuum medium, nevertheless, when simulating foam structures, foam is commonly assumed as a continuum, with homogeneous properties. This approach requires the calibration of the mechanical properties of the polyurethane adhesive layer, in order to compensate the effect of the foam’s discontinuous structure. The finite element method was used to numerically simulate a three-points bending test and an unconstrained bending test. The cohesive behavior was modelled by using a traction separation law. For the damage initiation criteria, a maximum-stress-based criterion was used, whereas for the damage evolution, a displacement-based damage evolution law was adopted. The experimental data were obtained from the group’s previous work, including a compression test, a tension test, a three-points bending test, and an unconstrained bending test.     

Stirring as foam disruption (SAFD) technique in fermentation processes

Foam reduction through stimng was studied in 20 L bioreactors with artificial media and with an actual biotransforma-tion process. For a given stirrer configuration and within a certain range of the broth mass, the foam height was correlated with the broth mass, i.e. the distance between upper stirrer and dispersion surface, and with the superficial gas velocity. Increasing the stirrer speed often resulted in reducing the foam height. A mechanistic model was developed for the Stirring As Foam Disruption (SAFD) technique, relating the foam height to the horizontal liquid velocity near the dispersion surface. The model illustrates the general applicability of the SAFD technique and points to foam entrainment as the major mechanism for the foam disruption.     

泡沫金属在熔盐相变蓄热中的强化传热特性

搭建了熔盐蓄热特性实验平台,开展相变蓄热过程传热特性实验研究。建立了蓄热容器二维轴对称、瞬态固液相变数学模型,相变过程模拟采用Solidfication & melting模型,相变区域采用Boussinesq近似,对比了纯硝酸盐蓄热工况和填加泡沫金属后蓄热工况数值模拟结果。采用实验与数值模拟相结合的方法,重点分析了泡沫金属对熔盐蓄热过程的强化传热作用。结果表明,填加泡沫金属能够有效提高熔盐换热速率,泡沫金属孔隙率越小强化蓄热效果越显著。泡沫铜的热导率较高,相对于泡沫镍和泡沫铝有更好的强化传热效果,蓄热速率是纯硝酸盐蓄热的1.6倍。在相变蓄热后期自然对流换热占主导地位,此时泡沫金属会抑制自然对流。同时,填加的泡沫金属越靠近容器中心位置,对自然对流抑制作用越强,蓄热性能越差。     

Integration of High‐Conductivity Graphite Foam to Metallic Systems Using Ag‐Cu‐Ti and Ag‐Cu‐Pd Braze Alloys

Graphite foams with low, medium, and high densities were joined to Cu‐clad‐Mo, 430 stainless steel, titanium, and Inconel 625 using Cusil‐ABA^® and Palcusil‐5^®. Copper‐clad‐molybdenum and steel were also joined to SiC‐coated foam. Well‐bonded joints with partially infiltrated foam and with carbon ligaments enriched with Ti formed in Cusil‐ABA joints of coated and uncoated foam. Low‐density foams showed greatest braze penetration and penetration distance decreased with increasing foam density. Foam/metal joints with Palcusil‐5 showed less penetration than Cusil‐ABA. The tension test on foam/Cu‐clad‐Mo and foam/430 stainless steel joints made using Cusil‐ABA revealed that the joints were always stronger than the foam.