泡沫铝室温声频内耗特征

采用声频内耗仪测定了泡沫铝在室温下不同振幅、频率的内耗，研究了泡沫铝的室温声频内耗特征，并讨论了泡沫铝内耗产生的机理。     

共析成分Zn-Al合金的相变内耗和DSC的研究

利用低频内耗和示差扫描量热计（ＤＳＣ）等技术研究了共析成分Ｚｎ－Ａｌ合金共析转变过程中的能量耗散问题，发现相变潜热和热滞均与相变的路径有关。相变内耗峰的峰高与频率倒数之间呈非线性关系，而对数减缩量与频率例数之间呈线性关系。证明了共析转变过程的内耗不仅具有滞弹性的性质，而且具有线性粘弹性的性质，相变内耗峰主要是线性粘弹性内耗的贡献。用Ｍａｘｗｅｌ模型对实验结果进行了解释。     

共析成分Zn—Al合金的相变内耗和DSC的研究

利用低频内耗和示差扫描量热计（ＤＳＣ）等技术研究了共析成分Ｚｎ－Ａｌ合金共析转变过程中的能量耗散问题，发现相变潜热和热滞均与相变的路径有关，相变内耗峰的峰高与频率倒数之间呈非线性关系，而对数减缩量与频率例数之间呈线性关系，证明了共析转变过程内耗不公具有粘滞弹性的性质，而且具有线性粘弹性的性质，相变内耗峰主要是线性粘弹性内耗的贡献，用Ｍａｘｗｅｌｌ模型对实验结果进行了解释。     

泡沫金属——高分子聚合物的复合体机械阻尼性能研究

本文研究了泡沫金属和同分子聚合物形成的复合体机械阻尼性能，结果表明它是一种内耗值Ｑ＾－１极高的阻尼材料，其阻尼特征表现为与应变振幅密切相关而与频率无显著关系的非线性内耗。同时研究了泡沫金属孔隙结构对复合体内耗值的影响关系，并对实验结果进行了讨论。     

含宏观孔开孔泡沫铝的阻尼机制研究

采用空气加压渗流技术制备了含宏观孔的开孔泡沫铝材料,通过多功能内耗仪采用内耗技术测试了泡沫铝在不同温度、不同频率和不同振幅下的内耗谱特征,研究表明与致密工业纯铝的阻尼能力相比,泡沫铝的阻尼能力得到很大的提高,泡沫铝的内耗随着测量频率的增加而增大,同时,内耗也随着应变振幅的增加而增大。经透射电子显微镜观察发现在晶界附近存在大量的位错亚结构。根据内耗测量和微观观察提出了泡沫铝中可能的阻尼机制:孔周围的应力集中和模式转换,孔洞/金属基体界面处由于动力学模量相差很大而使机械能转化为热能,孔洞发生不均匀的膨胀或畸变使外加应变能耗散为热能。     

泡沫Al孔结构的影响因素

揭示了泡沫化过程中Ａｌ熔体泡沫孔隙率、导热系数的变化规律,研究了泡沫Ａｌ的孔隙率、孔径以及导热系数的变化规律及其对应关系。结果表明：Ａｌ熔体泡沫的孔结构及导热系数随泡沫化时间而变化。Ａｌ熔体泡沫的孔结构直接影响其凝固后的孔结构,而导热系数则间接影响孔结构。     

孔结构对通孔泡沫Al非线性阻尼性能的影响

采用特殊方法制备可控结构的通孔泡沫Ａｌ，研究了孔结构对数非线性阻尼性能的影响规律。     

氯羟丙基磷酸酯对软质聚氨酯泡沫阻燃机理的研究

采用含活性氢的氯羟丙基磷酸酯（ＣＨＰＡ）参与ＰＵ发泡配方中的异氰酸酯反应，使生成的软质聚氨酯泡沫（软ＰＵＦ）分子含阻燃元素Ｃｌ、Ｐ而实现其阻燃化。研究结果表明，含１２ｐｈｒＣＨＰＡ的软质ＰＵＦ的阻燃性能可达ＧＢ１０８００－８９／Ｉ级。着重研究了ＣＨＰＡ对软质ＰＵＦ的阻燃机理，提出燃烧初期ＰＵＦ／ＣＨＰＡ中的Ｃ－Ｃｌ键断裂，释放出ＨＣｌ与磷酸酯作用，生成ＰＯＣｌ３、ＰＣｌ３、ＰＣｌ５等不燃性化合物。     

不同边界条件下泡沫铝硅合金的内耗特征

为了获得不同边界条件下泡沫金属的内耗特征,通过采用动态机械分析仪在不同弯曲模式下对泡沫铝硅合金的内耗进行实验研究.结果表明:泡沫铝硅合金在不同边界条件下的内耗峰出现情况不同,且温度对三点弯曲模式时内耗的频率特性影响最大;三种边界条件下泡沫铝硅合金的内耗的振幅效应基本相似;温度对该材料在三点弯曲模式比单双悬臂梁振动模式下内耗的影响更大.     

动态力学及介电法研究蓖麻油丙烯酸酯共聚网络悬挂链的弛…

用动态力学（内耗）和介电方法研究了由蓖麻油、甲苯二异氰酸酯（ＴＤＩ）、丙烯酸羟乙酯（ＨＥＭＡ）组成的网络（Ａｉ）和由正己醇取代Ａ网络中部分ＨＥＭＡ组成的网络Ｂ１（ｉ＝０，１，２，３）两种网络的内耗及介电损耗，内耗峰强度随悬挂链数目增加而升高，证实了网络破坏后形成的悬挂链的运动对内耗及介电损耗峰高有明显的贡献。     

Internal friction of foamed aluminium in the range of acoustic frequencies

The internal friction of aluminium foams with various porosities was measured in the range of acoustic frequencies over a wide strain-amplitude range by the bending-vibration method. The measured internal friction shows that aluminium foams have a damping capacity which is enhanced in comparison with bulk aluminium, increases with increasing porosity, decreases with increasing frequency and increases with increasing strain amplitude. In order to explain the behaviour of the internal friction, a mechanism of internal dissipation energy was presented, and an approximate expression for internal friction is derived which is based on the equations of plane waves in elastic material with voids. This expression can account for the dependence of the internal friction on porosity, pore size and frequency. To gain further insight into the dependence of the internal friction on amplitude, the non-linear characteristics of oscillations were observed, and it was found that the resonance curves are asymmetric and the resonant frequencies are proportional to the square of amplitude with a negative slope. On the basis of the equations of the motion and the experimental results, the non-linearity of oscillations was ascribed to a non-linear damping term and an approximate expression for the damping coefficient with respect to amplitude was obtained. © 1998 Chapman & Hall     

多孔性吸声材料的研究进展

本文阐述了吸声材料在实际使用中的地位和意义,简单介绍了多孔吸声材料的种类及其性能特点.详细介绍了多孔泡沫吸声材料,其内容涉及泡沫金属材料的制备工艺、吸声性能和影响因素,以及泡沫塑料、泡沫玻璃和复合泡沫材料的特性、用途、研究进展和应用现状.     

铝合金基石墨复合材料的阻尼行为

用内耗技术研究了石墨颗粒/铝硅复合材料的低频阻尼行为,考查了阻尼对石墨含量、测量频率、温度和应变振帽的依赖关系以及相应的弹性模量的变化,比较了铸态和挤压变形复合材料的阻尼特征.对其阻尼机制作了初步的探讨.     

泡沫铝-聚氨酯复合结构的缓冲性能研究

研究了以泡沫铝为基体,以聚氨酯为增强体组合而成的泡沫铝-聚氨酯复合结构,其综合性能优于原组成材料而满足各种不同的要求。利用Ansys软件建立了泡沫铝-聚氨酯缓冲包装装置模型,通过分别填充体积比例为4.31%,8.04%及12.15%的泡沫铝,用Ansys对缓冲包装装置进行了应力分析,得到了装置各部分的变形情况,分析了装置的冲击吸振性能;仿真结果表明:在加速度达到7 800g时,该装置缓冲性能优于单体。     

Microstructure and internal friction of spray deposited Al-3.3Fe-10.7Si alloy

Al-3.3Fe-10.7Si alloy has been experimentally made with spray deposition technology. The internal friction of the alloy which was directly associated with the microstructures under spray deposited, extruted and heat treated conditions has been investigated using a low frequency inverted torsion pendulum over the temperature region of 10–300 °C. An internal friction peak was observed in the temperature range 50–250 °C in the present alloy. The Q^-1 peak decreased after extruted and in subsequent to the earliness of isothermal annealing, which was found to be directly attributed to the precipitation of FeAl₂ and Al– Fe– Si intermetallics from the supersaturated aluminium alloy matrix. We suggest that the internal friction peak in the alloy originates from grain boundary relaxation, but the grain boundary relaxation can also be affected by FeAl₂ and Al– Fe– Si intermetallics at the grain boundaries, which will impede grain boundary sliding.     

Investigation of the distribution and the state of rare earth elements in pure aluminium by the method of internal friction

This paper is the first part of an investigation of the distribution and the state of rare earth (RE) elements in aluminium by the method of internal friction. The grain boundary internal friction was measured for 4N pure aluminium samples with various RE contents (0 to 3%, nine in number) with a high vacuum Ke torsion pendulum. It has been found that the peak height and the background decrease with increasing RE content up to 0.5%, and that when RE content > 0.5% the peak height changes little but the background rapidly increases with RE content. A series of grain boundary internal friction parameters were obtained with the help of conventional and new methods. The various behaviours of RE in aluminium were discussed from the effect of RE content on the relaxation strength and the activation energyH. The relation between the parameter _H, which is a measurement of the distribution width ofH, and RE content was inferred.     

泡沫镍吸声性能的研究

本文详细的研究了泡沫镍中高频的吸声性能。试验表明：泡沫镍是一种性能优良的吸声材料,在高频具有较高的吸声系数;通过吸声结构的设计可以提高其在低频的吸声性能。