Preparation of aluminum foam sandwich by rolling-bonding/powder metallurgy foaming technology

Aluminum foam sandwich was prepared by rolling-bonding/powder metallurgical foaming technology, and the effects of rolling on bond strength of face sheet/powders and powder density were studied. Moreover, the foaming agent, TiH2, was heat treated and a certain amount of Mg was added into powder in an attempt to understand how the stability and uniformity of foam was improved. The experimental results show that the foaming precursors with ideal quality were obtained by rolling-bonding process. When rolling reduction is 67%, the consistency of powders reach to 99.87%. Throughout consideration of the bonding of face sheet/ core layer powders and deformation characteristic of powders, the optimum rolling reduction is 60%-70%. Cracks and drainage during foaming were inhibited by heat treatment of foaming agent TiH2 and the addition of a certain amount of Mg. The optimum heat treatment way of TiH2 is that heat preserving 1 hour at 450 ℃; the amount of adding Mg is 1wt%.     

混凝土发泡剂的复配研究

泡沫混凝土已经受到广泛的关注,但发泡剂的泡沫性能却不能满足制备高品质泡沫混凝土的需要.为了探索提高发泡剂性能的方法,分别选用十二烷基磺酸钠、聚乙二醇、明胶和自制蛋白稳泡剂,对十二烷基苯磺酸钠进行了复配研究.通过测量发泡剂携液量、发泡倍数、保水系数的变化规律表征外加剂对发泡剂泡沫性能的影响,并对产生影响的原因进行了解释.结果表明,只要复配条件适当,4种外加剂都能在一定程度上改善十二烷基苯磺酸钠的泡沫性能,其中蛋白质稳泡剂的效果最好,复配条件要求低.可见,通过复配提高发泡剂的性能是一条有效途径.     

CaO-SiO_2-MgO脱硅渣起泡性能的研究

分析了铁水脱硅预处理后炉渣起泡原因及机理,通过实验验证并提出了抑制炉渣发泡的措施.研究表明：将氧化剂连续、分散加入铁液,可减少单位时间内发泡气体的产生量,有利于抑制炉渣发泡.1450℃条件下,当碱度为0.6～0.8,w（MgO）为10%～20%时,碱度升高或w（MgO）增加,炉渣黏度呈降低趋势,密度变化不大,而发泡高度和发泡指数明显减小.随着w（MgO）增加,炉渣表面张力增大.炉渣碱度为0.8、w（MgO）为20%时,发泡性能最弱.向脱硅渣中加入适量CaO或MgO,可改变炉渣的物理化学性质,抑制炉渣发泡.     

熔渣泡沫化的实验研究

对熔渣泡沫化进行了实验研究。实验在实验室小型硅化记上进行,同时在１０００ｋｇ中频感应炉上进行了热模拟实验。测试了熔渣碱度、熔渣中ＣａＦ２含量、发泡剂碳加入量过剩指数等因素对发泡指数的影响,经过对熔渣发泡机理的理论分析,建立了熔渣发泡需气量与熔渣粘度、表面张力的关系。     

露天矿潜孔钻机泡沫发生器的性能实验

为解决露天矿潜孔钻机作业粉尘污染严重的问题,从传统除尘技术应用效果差、耗风量大、取水困难等事实出发,根据泡沫除尘机理及两相泡沫发泡原理,设计了一种适用于露天矿潜孔钻机的泡沫发生器,并对其发泡性能进行研究.通过开展泡沫发生器的泡沫流量、发泡倍数及半衰期等性能实验,确定出影响泡沫发生器发泡性能的主要因素,得出泡沫发生器的最佳工况点.实验结果表明:气体流量、液体流量(气液比)、发泡网及发泡剂质量分数是影响泡沫发生器发泡性能的4个主要因素,在工况为发泡网1、质量分数1.5%的配方2、气体压力0.7 MPa、液体流量18 L/min及气体流量30 m~3/h条件下,泡沫发生器发泡性能达到最佳,其流量为515 L/min,发泡倍数为22,半衰期为65 min.经现场试验,泡沫除尘后采场平均降尘率高达90%以上,应用效果良好.     

Preparation of ceramic foams suitable for aircraft arresting by the airport runway based on a protein foaming agent

Crushable ceramic foams are more suitable to be used as an arrestor material applied in engineered materials arresting system(EMAS) for airport runway for their properties of widely controllable strength, negligible crushing-rebounding behavior, durability, and chemically-inert composition, comparing with traditional concrete foams. The synthesis of ceramic foams adopted direct-foaming method and used an animal protein as foaming agent. Kaolin, talc powder and alumina were the main raw materials. Effects of the ratios of raw materials, calcination temperatures, heating rates, holding time, viscosities of polyvinyl alcohol(PVA) solution as well as the amounts of protein foaming agent and water on microscopic structure, densities, compressive strength and open porosities of ceramic foams were investigated systematically. The results indicate that ceramic foams with typical pore sizes 100-300 μm, open porosities from 73.1% to 91.5%, densities from 0.25 to 0.62 g·cm-3, compressive strength from 0.19 to 4.89 MPa, are obtained by properly adjusting the parameters mentioned above. And the mechanical strength meets the requirement for the EMAS for airport runway. In addition, good correlations are observed among compressive strength, open porosity, microscopic structure, and crystal phase. Furthermore, the possibility of producing the general dimensions of such aircraft arresting components with the proposed method was also discussed.     

Thermal properties of open-celled aluminum foams prepared by two infiltration casting methods

Contrastive research was carried out to study the thermal properties of open-celled aluminum foams prepared by counter-gravity infiltration casting system and the traditional process respectively.The experimental results show that the thermal conductivity coefficients of aluminum foams prepared by two different infiltration methods have similar increasing trend with the increase of particle size; along with the reducing porosity,the thermal conductivity coefficients will be enhanced oppositely.However,with the same particle size,the open-celled aluminum foam prepared by the former method has a higher thermal conductivity coefficient obviously.It is largely because that the sample prepared by counter-gravity infiltration casting has a lower void content and better dense crystallization of metal-matrix after the constant pressure process.     

泡沫铝夹芯板的粉末冶金制备工艺

采用包套轧制法成功制备出了泡沫铝夹芯板,该工艺使泡沫铝夹芯板的面板与芯层达到了冶金结合．重点研究了发泡参数对泡孔生长的影响及泡孔的演变行为．结果表明：发泡温度、冷却速度与最终的发泡效果密切相关．发泡过程中,夹芯板芯层泡孔经历了气泡的形核、长大和合并等过程．     

LF-VD过程泡沫渣的应用与控制

分析了ＬＦ和ＶＤ精炼过程泡沫渣的作用及影响因素,进行了１５０ｔ ＬＦ的全程埋弧操作试验。结果表明,实现ＬＦ的全程埋弧操作可以使吨钢电极消耗和电耗分别下降了２６．６％和１２．５％,而钢包的平均寿命却提高了２６．８％,并能保证ＬＦ的精炼效果,使出钢至ＬＦ处理结束钢波的脱硫率达到６９．９％;而钢液在ＶＤ的脱硫率可以达到３８．６％。ＶＤ处理过程应当通过优化抽真空制度和吹氩制度以及在ＬＦ处理结束前调整钢包顶     

稀土电解电容器铝箔制备过程中的织构演变规律

采用蚀坑法、EBSD微取向分析和X射线法等手段,对稀土电解电容器用铝箔制备过程中的织构演变规律进行了研究.结果表明,冷轧态织构主要要类型是立方织构({001}《100》)、黄铜织构({011}《211》)、高斯织构({011}《100》)、S织构({123}《634》)和铜型织构({112}《111》).铝箔的再结晶织构主要类型是立方织构({001}《100》)、高斯织构({011}《100》)、R织构({124}《211》).随着Ce含量的增加,稀土铝箔的再结晶织构中立方织构增加,但并不是越多越好.在稀土的质量分数为0.007 4%时立方织构含量最多.同时R织构随Ce含量的增加先减少,后略有增加.随着再结晶退火温度的增加立方织构的含量增加,R织构含量减少,在530 ℃退火时立方织构含量最多.     

泡沫评价及发泡剂复配的实验研究

介绍了泡沫的主要评价方法,将各种不同性质的发泡剂进行复配,复配后实际的泡沫体积Vr大于理论计算的泡沫体积Vt,就认为有增泡作用,反之则为消泡作用.据此,选出了九组有增泡作用的复配系统,六组有消泡作用的复配系统.     

酚醛泡沫保温材料的制备及性能研究

采用戊烷系复合发泡剂、有机无机酸复合固化剂、表面活性剂吐温-80和自制的可发性酚醛树脂制备酚醛泡沫,研究了固化温度、固化剂、发泡剂对酚醛泡沫表观密度的影响规律,找到较理想的原料配比,通过实验证明,其主要性能指标优异,对酚醛泡沫的应用具有重要的指导意义.     

稀土复合玻璃澄清剂的研究

对不同的玻璃澄清剂及其含率对玻璃液澄清效果的影响进行了研究;着重研究了稀土复合澄清剂对玻璃液澄清效果的影响,并对澄清机理进行了探讨。对比实验结果表明：稀土复合澄清剂比单一的澄清剂具有更好的澄清效果。     

泡沫铝在船舶舱室中的降噪应用

针对船舶舱室内的噪声问题,利用阻性吸声材料泡沫铝无毒、阻燃、无粉尘、工艺性能好的特点,模拟舱室环境,对舱室进行了噪声治理。模拟结果表明加泡沫铝后,可以使舱室空气噪声平均降低约10dB,具有显著的降噪效果。     

铝及铝合金阳极氧化膜的封闭技术

概括了铝及铝合金阳极氧化膜的几种常规封闭方法:水合封闭法、重铬酸盐封闭法、水解盐封闭法、常温金属盐封闭法等.介绍了两种铝及铝合金阳极氧化膜的封闭新技术:有机酸封闭和稀土封闭法,分别比较了不同封闭方法的优缺点.指出由于稀土元素对铝合金有很好的缓蚀作用,并且无毒性,因此,稀土元素在铝及铝合金阳极氧化膜封闭处理中的研究具有非常广阔的应用前景,提出了在今后工作中需要进一步深入研究的问题.     

Shock wave compression behavior of aluminum foam

1　INTRODUCTIONInrecentyears ,aluminumfoamsofhighporosityhaveattractedmuchattentionofresearchersonmate rialsduetotheiruniquecompressionbehaviorthatun dergoesalargedeformationatnearlyconstantnominalstress ,andgreatpotentialforapplicationinabsorbingenergyfromimpact[1 3] .Thisapplicationthereforere quirestheknowledgeontheshockcompressionbehav iorofthealuminumfoamundervariousimpactcondi tions.AlthoughanumberofworkonthedynamicpropertyofaluminumfoamshasbeenperformedwithsplitHopkinson pressureba…     

铝及铝合金阳极氧化膜的封闭技术

概括了铝及铝合金阳极氧化膜的几种常规封闭方法：水合封闭法、重铬酸盐封闭法、水解盐封闭法、常温金属盐封闭法等。介绍了两种铝及铝合金阳极氧化膜的封闭新技术：有机酸封闭和稀土封闭法，分别比较了不同封闭方法的优缺点。指出由于稀土元素对铝合金有很好的缓蚀作用，并且无毒性，因此，稀土元素在铝及铝合金阳极氧化膜封闭处理中的研究具有非常广阔的应用前景，提出了在今后工作中需要进一步深入研究的问题。     

高性能防灭火三相泡沫的实验研究

提出了用三相泡沫来防治煤炭的自燃．由粉煤灰或黄泥、氮气和水通过物理机械方式形成的防灭火三相泡沫,具有集固、液、气三相材料的防灭火性能于一体,充分利用粉煤灰或黄泥的覆盖性、氮气的窒息性和水的吸热降温性进行防灭火的特性．通过对优选的4种发泡剂及相互复配对泡沫性能的实验研究,得出了最优的复配发泡剂及配比．同时研究了发泡剂质量分数、水玻璃质量分数及浆液质量分数对制备高性能三相泡沫的影响．结果表明,当发泡剂质量分数为0．2％,水玻璃质量分数为2％,灰水质量比为1：4时,制得的防灭火三相泡沫的性能最好．并在实验室构建的三相泡沫实验系统上制备出了高性能的防灭火三相泡沫．     

泡沫铝填充6082-T6铝合金圆管构件轴压力学性能

薄壁金属构件与吸能泡沫材料组合形成的复合构件具有优越的耗能性能,本文将泡沫铝填充至6082-T6高强铝合金圆管中作为建筑结构中的耗能复合构件。为获得泡沫铝填充6082-T6铝合金圆管在轴压荷载下的响应特征、破坏机理及耗能性能,进行了20组不同径厚比和高径比的铝合金空管以及泡沫铝填充复合管的轴压试验。构件表现出3种破坏模式:劈裂破坏、叠缩劈裂破坏、叠缩劈裂+不规则变形破坏。填充泡沫铝能够有效改善构件在轴压荷载下的变形能力,避免其发生不规则变形破坏,并提高构件耗能能力。基于有限元分析平台LS-DYNA提出了合理的有限元建模方法并开展了参数分析,结果表明:构件峰值承载力与吸能能力均随壁厚和管径的增大而增大。当高径比增大时构件在轴压荷载下发生失稳破坏,而填充泡沫铝后构件发生失稳破坏的临界高径比增大。     

秸秆粉／PP微孔发泡复合材料的发泡工艺研究

本文主要通过AC发泡剂含量、EVA含量、偶联剂种类和含量及挤出机的工艺参数等单因素来研究最佳发泡工艺．结果表明：AC发泡剂含量为4份时,密度最小为0．95g／mm2,冲击强度最大为14．88KJ／m2;随EVA含量的增加,密度减小,冲击强度增大,12％以后密度与冲击强度基本不变,密度达到最小0．84g／mm2,冲击强度最大11．4KJ／m2;MAH-g-PP6份时冲击强度达到最大为11．56KJ／m2;制备发泡母粒时挤出机螺杆温度为150℃时,密度达到0．94g／mm2,冲击强度达到12．04J／m2．