树脂基复合材料表面隔热涂层的组织与性能研究

以碳纤维增强环氧树脂作为基体材料, 设计并制备了一种轻质、环保的隔热涂层。为解决基体材料与涂层之间热膨胀系数差别大导致易于开裂的问题, 同时实现具有高反射率和低热导率的目标, 通过添加聚氨酯、TiO₂、SiO₂、Al₂O₃等填料制备连接层、阻隔层、反射层等三个不同功能层形成复合隔热涂层。通过优化涂层脱落时间、反射率、热导率等, 得到连接层、阻隔层、反射层最优厚度分别为80、120和90 μm。优化后的隔热涂层具有优异性能: 涂层的反射率高达0.95, 导热系数为0.048 W·m ^-1·K ^-1, 隔热温差为20.1 ℃; 耐热冲击性能良好, 190 ℃的最大失重率为3.7%, 并在随后保持稳定; 在160 ℃连续保温4 h后表面变黄, 但无明显脱落现象, 同时, 纳米填料颗粒保持原状态。     

超细玻纤环氧复合材料的隔声与隔热性能

以超细玻璃纤维绵和环氧树脂为原料,制备了含量不同的超细玻纤环氧复合材料。由于超细玻璃纤维的引入,对入射声波的散射作用增加,因此该类材料具有较好的声音阻隔性能,同时,由于环氧树脂基复合材料本身较低的导热系数,该类材料同时具有较好的隔热性能。采用阻抗管测试方法、导热系数测定和冲击性测试,对复合材料的隔声隔热及抗冲击性进行了表征,结果表明,引入超细玻纤的环氧树脂复合材料隔声量能达到50dB以上,导热系数降低至0.167W/(m·K),具有良好的隔声隔热性能。     

Study on the Thermal Expansion and Thermal Cycling of AlNp／Al Composites

The AIN particle reinforced aluminum matrix composites with 50% volume fraction were fabricated by squeeze-casting technology.The thermal expansion behavior and its response to thermal cycling were studied between 20℃ and 400℃.Compared with four theoretical models,the measured CTEs of the composite lie within the elastic bounds derived by Schapery′s analysis .Schapery′s model and Kerner′s model agree well with the CTEs of the composites at lower temperature and elevated temperature,respectively.Strain hysteresis was observed between heating and cooling curves during cycling.This was attributed primarily to the anelastic behavior of the matrix induced by matrix residual stresses.     

湿热老化对碳纤维/环氧树脂基复合材料力学性能影响研究

研究了3.5%(质量分数)NaCl溶液和去离子水两种介质分别在30℃和80℃两个温度下溶液浸泡对碳纤维增强树脂基复合材料力学性能的影响.研究发现:浸泡使复合材料的力学性能下降,80℃下浸泡使复合材料力学性能下降更显著;低温下介质组分对复合材料的影响不是很明显,80℃下去离水中浸泡对复合材料的静态力学性能破坏更显著.     

Application of Interlaminar Tests to Marine Composites. Relation between Glass Fibre/Polymer Interfaces and Interlaminar Properties of Marine Composites

The need for improved performance and the development of new composite manufacturing methods require a better understanding of the role of interface phenomena in the mechanical behaviour of these materials. The influence of the cure cycle on the bulk and surface properties of the matrix resin, and of composites based on polyester and epoxy resins reinforced with glass fibres has been studied. While the mechanical properties of the epoxy vary with cure temperature the surface tension is not affected. The increase in interfacial shear strength and interlaminar shear strength with increased cure temperature cannot be simply explained by the wetting of the fibres by the matrix. The importance of thermal stresses, generated at the interface by resin shrinkage and differences in thermal expansion, for the mechanical behaviour of the composite are demonstrated.     

光棒废料改性环氧树脂复合材料的制备和性能

将光棒废料烘干、破碎、煅烧和研磨,分别由KH-570和A-151表面改性制备KH-570/SiO₂和A-151/SiO₂废料粉末,再把改性前后的粉末分别与EP共混固化制备出复合材料。疏水性测试、FT-IR和SEM观测的结果表明,两种偶联剂对废料颗粒的改性效果较好,其中A-151的改性效果更好。几种复合材料拉伸性能的排序为A-151/SiO₂/EP＞KH-570/SiO₂/EP＞未改性粉末/EP,且粉末填充质量分数为20%的材料拉伸性能最优,其拉伸强度分别为49.37 MPa、45.57 MPa、44.36 MPa,比纯EP固化物分别提高了19.9%、10.7%和7.8%,断裂伸长率的提高量最大,比纯EP固化物分别提高了0.92%、0.82%和0.46%。改性效果好的废料粉末填充制备的复合材料,其耐热性能更优。     

磨碎玻璃纤维增强环氧树脂复合材料的制备及力学性能研究

用硅烷偶联剂对磨碎玻璃纤维表面进行改性,并制备玻璃纤维/环氧树脂复合材料,采用超声分散对复合材料分散处理,探讨不同磨碎玻璃纤维粉质量比对环氧树脂基复合材料压缩、拉伸性能的影响。研究表明,添加磨碎玻璃纤维后,环氧树脂的强度和硬度显著增强。当磨碎玻璃纤维掺量在15%~25%之间时,复合材料的综合力学性能最好,其压缩强度、压缩模量、拉伸强度最高达到67.1 MPa、1.68 GPa、57.6 MPa,与纯环氧树脂相比提高了24%、35%、34%;断裂伸长率随着掺量的增加逐渐降低,当含量达到30%时比纯环氧树脂的降低了48%,表明添加玻璃纤维粉后环氧树脂脆性增强。目数小粒径较大的玻璃纤维粉对环氧树脂力学性能增强效果更优,但影响程度不如含量对复合材料力学性能的影响大。     

碳(石墨)/环氧复合材料及其在航天器上应用研究进展

综述了空间环境因素的特征及其效应,包括太阳电磁辐射、带电粒子辐射、空间真空效应、冷黑环境、原子氧侵蚀、微流量和空间碎片的撞击。碳（石墨）纤维、环氧树脂、碳（石墨）／环氧复合材料的性能以及碳（石墨）／环氧复合材料在航天器上的应用和研究现状。     

环氧树脂及其复合材料微波固化研究进展

在介绍微波固化技术的原理及其优点的基础上,综述了环氧树脂及其复合材料的微波固化研究进展,重点讨论了微波固化对环氧树脂及其复合材料固化体系的固化速率、固化产物力学性能和热性能的影响,介绍了颗粒增强环氧树脂和纤维增强环氧树脂两种适合微波固化的复合材料系及工业应用关键技术问题,并对环氧树脂及其复合材料微波固化的应用前景进行了展望。     

真空热循环对空间级缩合型硅橡胶拉伸性能的影响

对空间级缩合型硅橡胶KH－X－B进行了真空热循环试验（123－403K，10^-5Pa），测试了热循环前后材料的质损率，拉伸性能，热膨胀性能，讨论了循环过程中的应变滞后效应和附加残余应变以及它们对材料的强化作用，结果表明，材料质损率随循环次数增加而提高后趋于平缓，室温及高温拉伸强度随循环次数的增加是先增强而后下降，循环过程中发生应变滞后现象，且第一次循环后产生附加残余应变，206次循环后残余应变消失，材料强化，400次循环后重新产生残余应变，材料强度下降。     

Effects of Shear‐Transverse Coupling and Plasticity in the Formulation of an Elementary Ply Composites Damage Model,Part I: Model Formulation and Validation

Abstract: Continuum damage mechanics (CDM) models have been employed successfully in the literature to predict the response of laminated composite materials. Some sophisticated models can include the effects of non‐linear shear and transverse damage progression, plasticity and shear‐transverse damage coupling. However, these models require non‐standard test data for calibration that may not always be available to a modeller. In this two‐part study, we examine the effect of neglecting plasticity parameters, and also the effect of neglecting both plasticity and shear‐transverse coupling parameters in simplified CDM models for predicting monotonic tensile strength. In part I, we develop simplified versions of the CDM model and test their ability to accurately predict the failure response of angle‐ply laminates. In part II, we provide details of the experimental test series carried out to determine the input parameters for the models. It was found that neglecting plasticity requires some approximations in the damage development laws, but the resulting model can predict well the response of the angle‐ply laminates tested under monotonic loading to failure. Neglecting shear‐transverse coupling is acceptable for the some materials.     

热循环对预应变NiTi记忆合金丝/铝基复合材料马氏体逆相变的影响

采用热压法将0.26mm的NiTi合金丝复合于铝中,利用SEM,DSC,热膨胀仪等实验手段研究了热循环对预应变为4%的NiTi合金丝/铝基复合材料马氏体逆相变的影响。结果表明,在第一次加热过程中,马氏体逆转变开始温度明显升高;第二次加热过程中逆转变开始温度比未预应变样品略有降低;随热循环次数增加,逆相变开始温度降低;当循环次数超过30次后,逆转变温度几乎保持不变。并对热循环过程中的马氏相变过程进行了分析讨论。     

金属基复合材料中热残余应力的分析方法及其对复合材料组织和力学性能的影响

对目前金属基复合材料热残余应力的分析方法进行了概述,并对热残余应力对金属基复合材料的性能影响进行了分析,提出了目前在复合材料热残余应力的实验分析和理论计算中仍存在的问题以供材料科学工作者共同研究解决.     

接枝改性对F-12纤维及其环氧复合材料力学性能影响的研究

采用稀氢氧化钾溶液对Ｆ－ １２ 纤维表面进行处理,将—ＣＯＯＫ 基团引入到Ｆ－ １２纤维表面,作为环氧氯丙烷接枝的引发剂．并分析了温度和时间对Ｆ－ １２ 纤维拉伸强度及其环氧复合材料层间剪切强度的影响．表明：在温和条件下将—ＣＯＯＫ 基团引入到Ｆ－ １２纤维表面,进而引发环氧氯丙烷的接枝,可以提高Ｆ－ １２环氧复合材料的层间剪切强度,而纤维的拉伸强度只有较小的损伤．     

BN&AlN&SiC/环氧树脂复合材料线膨胀系数对LED寿命的影响

在全球大规模推广使用LED照明的今天,使用寿命是制约LED发展的瓶颈,其中,封装材料的线膨胀系数对大功率LED的使用寿命具有重要的影响。由于大功率LED粘接层材料比其相邻材料的线膨胀系数大,在循环工作时各层之间的膨胀收缩不一致,导致层与层之间产生翘曲裂纹现象,从而影响LED的使用寿命。文中采用向环氧树脂(EP)中分别加入氮化硼(BN)、氮化铝(AlN)、碳化硅(SiC)微粉颗粒制备出3种——BN/EP、AlN/EP、SiC/EP复合材料,并对其进行对比分析。研究结果表明,BN/EP复合材料性能最佳,线膨胀系数可降至3.86×10-5 K-1。且当BN质量分数为55%时,导热系数达到1.598 W/(m·K),粘接强度为53.83 MPa。与纯环氧树脂相比,可使1 W LED芯片结温降低约29.6℃,寿命提高约2.2×104 h。     

Perspective Measurement of the Out‐of‐plane Displacement and Normal Strain Field Distributions Inside Glass Fibre‐reinforced Resin Matrix Composite

A depth‐resolved wavenumber‐scanning interferometer (DRWSI) was built up to measure the out‐of‐plane displacement and normal strain field distributions on the front surface, rear surface and internal glass fibres of a glass fibre‐reinforced resin matrix composite before and after loading. Series of the fringe patterns were recorded, while the wavenumber of the laser, monitored online by an optical wedge, was scanned by tuning the temperature. Random sampling Fourier transform is used to overcome the non‐linearity of the wavenumber series. In the end, the distributions of the out‐of‐plane displacements and normal strain field are presented as the applied loads were 10 µm, 20 µm and 30 µm, respectively. In conclusion, DRWSI is a suitable method to measure the mechanical properties inside resin composite non‐destructively.     

阳光暴晒对环氧树脂基复合材料涂层附着性能的影响

为了解风电叶片生产过程中阳光照射时间对叶片材料表面涂装质量的影响,对环氧树脂基复合材料壳体材料进行阳光下暴晒,使之达到一定的老化程度,在其表面进行聚氨酯胶衣涂装,考察了暴晒时间对胶衣与复合材料间附着力的影响.研究表明,随着暴晒老化的进行,胶衣对基体的附着力呈下降趋势,老化5天时附着力由初始的9MPa左右平缓下降到7MP...     

玻璃纤维的预处理及含量对硅质隔热材料性能的影响

以玻璃纤维、气相法白炭黑、TiO_2及结合剂为原料,采用干法成型工艺制备了玻璃纤维增强硅质隔热复合材料,系统研究了玻璃纤维预处理技术及其含量对材料导热性能及力学性能的影响,并且观察了其微观形貌。结果表明,纤维表面预处理可有效提高其在基体中的分散性,改善其与基体的界面粘结性;纤维最佳含量为20%;在200℃、500℃和900℃时其热导率分别仅为0.029W/(m·K)、0.033 W/(m·K)和0.043W/(m·K),耐压强度为1.38MPa;与未添加纤维的硅质隔热材料相比,热导率降低21%～28%,耐压强度提高了116%。