无损检测在复合材料中的应用

介绍目前常用的各种无损检测方法．随着复合材料的不断发展,通过无损检测的方法对产品进行质量控制,得到了广泛的应用．     

介电分析法在热固性树脂固化研究中的应用

本文介绍了介电分析法在热固性树脂及以其为基体的涂料和纤维增强复合材料固化研究中的应用。     

复合材料在工程机械中的应用

分析了现有工程机械车辆部分部件沿用传统材料的落后和不足，将现代复合材料的优越性与当前工程机械的设计结合，对复合材料在其中的应用进行了试探性研究，阐述了其优点，并进行了说明和举例。     

用介电分析法研究树脂基复合材料的固化制度及其对性能的影响

本研究用介电法测定树脂基复合材料的固化温度以及在各恒温阶段达到稳定所需要的时间;以介电法测出的固化温度和固化时间为基准,通过树脂浇铸体、强力环和单向板等试件进行性能对比,获得最佳的固化制度——二阶段恒温固化。     

玻璃微珠在复合材料中的应用

本文介绍了空心玻璃微珠的基本性能及其在复合材料中的应用。     

树脂基复合材料在欧美汽车制造业中的应用

本文叙述了近几年来树脂基复合材料在欧美汽车制造业中的应用，市场特点、产品开发和各大生产厂家的生产状况及产量，并对今后的一些重点发展领域和潜在市场进行探讨。     

射线检测在复合材料无损检测中的应用

复合材料必须通过一定的检测技术验收合格后才可以投入使用.通常采用无损检测技术对复合材料进行检测,与传统的检测技术相比,无损检测技术具有不可比拟的优点,可以弥补传统检测技术的不足.无损检测技术包括磁粉检测、超声波检测、射线检测、渗透检测、涡流检测等.本文重点阐述了射线检测的基本原理及其在复合材料无损检测中的应用.     

电子封装用液态环氧树脂中陶瓷填料的改性研究

选用氮化硼(BN)、氮化铝(AlN)、氧化铝(Al2O 3)、氮化硅(Si3N4)、二氧化硅(SiO2)添加到液态环氧树脂中制备复合材料,并对其进行黏度、热导率、热膨胀系数和介电常数的测试.结果表明:层片状的BN添加到液态环氧树脂中后,复合材料获得了较好的综合性能,即在体积分数为35%时,具有较高的热导率(2.12 W/m·K)、较低的热膨胀系数(38.13×10-6 K-1)、较低的介电常数(4.01,1 MHz).     

环氧树脂多孔复合材料的制备及性能

以环氧树脂为基体、蓖麻油酸(RA)或二聚蓖麻油酸(DRA)改性的四乙烯五胺(TEPA)(RATEPA/DRATEPA)作为固化剂、水为致孔剂、釉粉为无机填料,通过树脂-水-填料悬浮乳液复合体系聚合法,在室温下合成了环氧树脂多孔材料,采用SEM、压汞仪、电子万能试验机、TGA对多孔材料的形貌、孔径分布、孔隙率、机械性能及热性能进行了表征和测试。结果表明:随着水相质量分数和填料粒径的增大,多孔材料的孔径和孔隙率增大,压缩强度减小;随着固化剂分子量的增大,多孔材料的孔径和孔隙率减小,压缩强度增大。当填料粒径为40μm,固化剂为RATEPA,m(水相)∶m(树脂相)=2∶1时,多孔材料的综合性能最佳,其最可几孔径为3.449μm,孔隙率为21.8%,压缩强度为26.89 MPa。TGA和DTG测试结果表明:环氧树脂多孔材料的热稳定良好,具有耐高温性能,可以在高温条件下应用。     

Microwave Dielectric Properties of Rutile Filled PEEK Composites

Ceramic-filled PEEK composites were prepared by sigma mixing followed by thermolamination. Rutile-grade titanium dioxide, particle size less than 5 μm, was used as the particulate filler in the PEEK matrix to tailor the dielectric properties of the composite matrix. The dispersion of the particular filler in the PEEK matrix was studied using scanning electron microscopy. The dielectric properties of the PEEK/TiO₂ composite materials were measured in the low frequency region up to 13 MHz using an impedance analyzer. Dielectric properties in the microwave region were measured using cavity perturbation technique to evaluate the use of the composites as packaging material. Experimental results were compared with theoretically predicted values using the Lichtenecker equation. The present study shows that temperature-stable packaging materials can be realized in the PEEK/TiO₂ systems by judiciously controlling the ceramic filler concentration.     

SiO2/丁酮分散液的制备及其在环氧复合材料中的应用

通过机械球磨与偶联剂表面处理结合,制备得到高浓度含量、低黏度、分散稳定的SiO2/丁酮分散液。将分散液与环氧树脂混合、固化,制备得到环氧树脂/SiO2复合材料。研究了偶联剂GPTMS对SiO2/丁酮分散液的分散性能的影响。研究表明:加入质量分数为1%的偶联剂GPTMS,极大地提高了SiO2/丁酮分散液的分散性能及环氧树脂/SiO2复合材料的界面粘接性能。高含量SiO2的加入有效降低了复合材料的热膨胀系数,材料的玻璃化转变温度也有了一定的提高。     

The Preparation and Cure Kinetics Researches of Thermal Conductivity Epoxy/AlN Composites

The aluminum nitride (AlN) was employed to prepare epoxy/AlN composites by blending-casting moulding method, two different coupling agents were used to functionalize the surface of AlN. The thermal conductivity and mechanical properties of the composites were investigated. And the cure kinetics of the EP/AlN composites was studied by means of isothermal DSC. Results revealed that the thermal conductivity of EP improved remarkably with the addition of AlN, a higher thermal conductivity of 1.05 W/mK can be achieved with 42 vol% AlN, about 5 times higher than that of native epoxy resin. And the flexural and impact strength of the EP/AlN composites were optimal with 3.3 vol% AlN. The curing process of the EP/AlN composites contained autocatalytic mechanism, the whole process was according with the Kamal model. The presence of AlN did not change the cure reaction mechanism, and had little effecting on the activation energy, but decreased the rate constants k_l and k₂.     

Microwave Characteristics of Polyaniline Based Short Fiber Reinforced Chloroprene Rubber Composites

This report presents the microwave characteristics of conducting polymer composites (CPCs) based on chloroprene rubber with special reference to dielectric properties. CPCs based on polyaniline (PANI), polyaniline-coated short nylon fiber (PANI-N) and chloroprene rubber (CR) were prepared by mechanical mixing. The important properties like dielectric permittivity, loss tangent, conductivity, and dielectric heating coefficient were evaluated and compared. It was found that PANI/CR composites had very good dielectric properties in the microwave range. The addition of PANI-N improved the mechanical properties of the composites with reasonably good dielectric properties. The CPCs were also found to have good microwave absorption.     

SCRIMP用原位分相增韧中温环氧树脂体系制备及复合材料性能

针对复合材料真空辅助树脂浸渍模塑技术(SCRIMP)对树脂体系要求进行配方设计及性能测试。采用动态差示扫描量热(DSC)法,运用Kissinger动力学方程研究了基础树脂的固化反应动力学。通过添加QS-VA-3型原位分相型增韧剂,改善了基础树脂脆性,依据力学性能测试结果确定最佳添加量。对增韧环氧树脂体系进行等温/非等温黏度特性研究,确定了SCRIM P灌注成型过程的适用期,并使用该技术成型了增韧环氧树脂体系/单向玻璃纤维布复合材料试样,发现与玻璃纤维复合后具有强度高、界面性能好及低电压绝缘性能良好特点,但牺牲了高电压环境下绝缘性能。     

复合材料中纤维的抗拔机理

分析了纤维抗拔作用机理，建立了纤维抗拔作用的力学模型，用解析方法研究了纤维一基体之问应力与变形的一些规律，结合试验验证了该方法的合理性，提出了根据荷载传递函数确定纤维抗拔力的方法。     

共聚改性氰酸酯树脂及其性能

利用环氧树脂和双马来酰亚胺树脂做改性剂,对氰酸酯树脂进行共聚改性,通过对粘度的测量描述了共聚树脂的固化反应情况。性能测试表明内聚改性氰酸酯树脂的冲击强度比纯氰酸酯树脂自聚体提高了2倍多,可达12.3kJ/cm^2,热变形温度高达235℃,并具有优异的介电性能,如10kHz 介电常数为2.25,介电损耗角正切＜10^-4。共聚树脂中的配比和固化条件对性能有影响。     

芳纶复合材料抗爆震性能研究

采用圆形炸药设计了平面波发生器，运用薄膜型PVDF压电传感器，测量芳纶复合材料试件中冲击波压力。研究了三种树脂基复合材料抗爆炸性能。试验结果表明，三种复合材料中冲击波压力是随传播距离的增长而呈指数衰减，以Kevlar/SIS复合材料抗震性能最优。