搅拌法制备C／AI复合材料的界面问题

在碳纤维表面镀上一层金属铜镀层,用硼酸对其进行防氧化处理,采用机械搅拌法制取C／Al复合材料。利用扫描电镜、能谱分析和X射线衍射等手段对液态机械搅拌法制备的碳纤维增强铝基复合材料的界面微观结构进行了分析,结果表明,碳纤维表面镀铜,既可有效解决碳纤维与铝的润湿性问题,又可有效地阻挡碳纤维与铝的过度化学反应。硼酸作为保护剂,有效地解决了高温复合时镀铜层的氧化难题。Cu／Al界面生成大量的CuAl2金属间化合物,C-Cu／Al界面为混合界面：C／Cu界面和C／Al界面。     

搅拌法制备C/Al复合材料的界面问题

在碳纤维表面镀上一层金属铜镀层,用硼酸对其进行防氧化处理,采用机械搅拌法制取C/Al复合材料。利用扫描电镜、能谱分析和X射线衍射等手段对液态机械搅拌法制备的碳纤维增强铝基复合材料的界面微观结构进行了分析,结果表明,碳纤维表面镀铜,既可有效解决碳纤维与铝的润湿性问题,又可有效地阻挡碳纤维与铝的过度化学反应。硼酸作为保护剂,有效地解决了高温复合时镀铜层的氧化难题。Cu/Al界面生成大量的CuAl₂金属间化合物,C-Cu/Al界面为混合界面：C/Cu界面和C/Al界面。     

期刊文献

<正>支链化聚氧乙烯醚磺酸盐溶液的界面张力性质张路,刘岩,王策,胡嵩霜,张磊,赵濉,严峰摘要:利用旋转滴界面张力仪研究了不同烷基链长的支链脂肪醇聚氧乙烯醚磺酸盐异十六烷基聚氧乙烯醚磺酸盐(iC16EO5S)、异十八烷基聚氧乙烯醚磺酸盐(i-C18EO5S)和异二十烷基聚氧乙烯醚磺酸盐(i-C20EO5S)溶液与正癸烷之间的动态界面张力,考察了表面活性剂质量分数、盐质量分数、二价     

一种碳纤维表面复合涂层的制备方法

<正>一种碳纤维表面复合涂层的制备方法,它涉及一种复合涂层的制备方法。本发明的目的是要解决现有方法制备的碳纤维复合材料中碳纤维与树脂基体之间存在弱界面现状的问题。方法:①碳纤维的预处理;②涂覆;③固化;④碳化;⑤涂层官能团化,即得到碳纤维表面复合涂层。优点:①复合材料的层间剪切强度分别提高了20%~70%;②与     

POSS/GO复合接枝碳纤维/环氧树脂复合材料性能研究

在碳纤维表面逐层接枝多面体低聚倍半硅氧烷（POSS）和氧化石墨烯（GO）后,将其用于增强环氧树脂（CF/EP）制得复合材料,采用扫描电子显微镜、接触角测试和X射线光电子能谱等研究了POSS和GO复合接枝碳纤维对CF/EP复合材料力学性能的影响。结果表明,POSS和GO可以显著提高碳纤维的表面活性和比表面积,改善树脂与碳纤维的浸润性、反应性和机械啮合作用,从而提高复合材料的界面性能和力学强度。相比未改性碳纤维复合材料,POSS/GO复合接枝改性碳纤维复合材料的层间剪切强度（ILSS）提高了98.3%,弯曲强度提高了95.7%。     

γ-射线辐照对碳纤维及其复合材料力学陛能的影响

以^60Co γ-射线为辐照源对碳纤维（CF）表面进行处理，利用扫描电子显微镜（SEM）观察经辐照处理后的碳纤维单丝表面及其与环氧树脂制备的复合材料试样的层间剪切断付；通过层间剪切强度比较了吸收剂量对其复合材料层间剪切强度（ILSS）的影响，并根据GB/T 3362—1982标准比较了辐照前后碳纤维复照拉伸强度的变化。结果表明：辐照处理后的碳纤维增强环氧树脂复合材料的界面明显得到改善，在一定的吸收剂量范围内能够有效地提高复合材料的ILSS，但是过大的辐照剂量和接枝率不利于复合材料的界面改性；当辐照剂量小于250kGy时，碳纤维的复丝拉伸强度有所提高。     

尼龙66与碳纤维复合材料的界面效应和破坏机理的研究

采用尼龙66盐单体与碳纤维预先复合,然后进行原位固态缩聚和模压,可制得具有良好界面粘结的碳纤维—尼龙66复合材料。取决于所用碳纤维的特性,所得尼龙66复合材料具有不同的剪切强度和破坏机理。     

聚酰亚胺/滑石粉/碳纤维复合薄膜的界面性能研究

根据碳纤维表面性质和稀土元素独特的物理化学特性,采用稀土溶液(RES)表面改性方法对碳纤维进行表面改性处理,以改善聚酰亚胺/滑石粉/碳纤维(PI/talc/CF)复合材料的界面结合性能,从而有效地提高PI/talc/CF复合材料的力学性能。采用RES改性方法对碳纤维进行表面改性处理,制备出具有不同界面的PI/talc/CF复合材料。以PMDA-ODA型聚酰亚胺为研究对象,在制备的聚酰胺酸中加入不同量的滑石粉和不同RES浓度处理过的碳纤维这两者的混合物,通过5℃/min匀速升温工艺得到聚酰亚胺/滑石粉碳纤维复合薄膜。对制备的复合薄膜进行各种性能测试和结构表征。研究发现,经过RES处理过的碳纤维和滑石粉可以诱导聚酰亚胺分子围绕其结晶,碳纤维和聚酰亚胺之间界面结合良好。RES表面处理提高碳纤维与PI基体之间的界面结合性能,其中RES浓度为0.3wt%的改性处理方法最有效,拉伸强度提高了9.5%。     

国产T800S级碳纤维表面特性对复合材料界面性能影响研究

对两种国产T800S级碳纤维与进口T800S碳纤维表面特性及其复合材料界面性能的关联性进行了研究。通过扫描电镜（SEM）与原子力显微镜（AFM）对三种碳纤维的表面形貌与粗糙度进行了表征;采用X射线光电子能谱（XPS）对三种碳纤维表面化学官能团比例进行了分峰计算;通过碳纤维表面静态接触角对纤维表面浸润性进行了分析。制备并表征了碳纤维NOL环与单向复合材料的力学性能与微观破坏形貌,通过对比分析确定了影响复合材料界面性能的关键性因素,对复合材料界面性能的进一步提升具有指导意义。     

改变碱型对复配表面活性剂三元体系界面张力的影响

在复配表面活性剂(重烷基苯磺酸盐与石油磺酸盐比例为1:3)条件下,用强碱、弱碱、盐、以及三者之间复配后配制三元体系进行界面活性研究,通过对复配表面活性剂的弱碱三元体系在低碱低表面活性剂浓度下的界面张力扫描,绘制界面活性图,研究复配条件下强碱、弱碱、盐对三元复合体系界面张力的影响。     

短碳纤维增强铝基复合材料

通过化学镀再电镀的方法,在碳纤维表面镀上Cu镀层,制备C/Cu复合丝,并在硼酸的保护下,利用非真空条件下的液态机械搅拌法制备短碳纤维增强铝基复合材料,研究了碳纤维在复合材料中的分散程度,铜镀层存在状态及C/Al复合材料的拉伸性能.实验结果表明：在硼酸存在下,大大降低了铜的氧化程度,碳纤维分散均匀且没有损伤,少量硼酸的加入,对复合材料的力学性能没有影响,该复合材料的抗拉强度随碳纤维含量的增加而增加,其抗拉强度较基体材料提高50%以上,但塑性指标却明显下降.     

碳纤维表面化学镀铜工艺的优化

以甲醛为还原剂对碳纤维表面进行化学镀铜,利用正交实验对碳纤维化学镀铜工艺进行了优化,研究了施镀时间与镀层厚度及导电性之间的关系,确定了较理想的化学镀铜工艺。结果表明,采用优化后的碳纤维化学镀铜工艺制得的镀铜碳纤维镀覆均匀,光泽性好,镀层结合力强,导电性能显著提高。     

碳纤维表面连续镀铜工艺及性能研究

采用电化学沉积的方法在聚丙烯腈基碳纤维表面连续镀铜。利用CHI660电化学工作站测定了不同镀液的阴极极化曲线,以此优化镀液配方,并研究了工艺参数对镀层质量的影响。结果表明,以P2O74?与Cu2+质量比为7的镀液为基础镀液,加入20g/L柠檬酸铵,在温度40°C,pH=8.2～8.8和电流0.6A的条件下电镀60～150s,可以消除"黑心"和"结块"现象,得到均匀、细致、界面结合力良好的碳纤维表面镀铜层。镀后碳纤维导电性提高了150倍,但力学性能有所下降。     

镀铜碳纤维布的制备及性能研究

为制备新型毫米波无源干扰材料,采用化学镀方法在碳纤维布表面沉积了金属铜层。测量了优化工艺条件下制得的镀铜碳纤维布的表面电阻,并采用冷热循环法检测了镀层的结合强度,应用雷达散射截面(RCS)测试系统测试了同样尺寸的镀铜碳纤维布及未改性碳纤维布的3mm波段RCS值。结果表明:镀铜碳纤维布镀覆均匀,金属光泽强,有良好的镀层结合强度及较强的导电性能。镀铜碳纤维布在3mm波段的RCS值较未改性碳纤维布有很大提高,且与理论计算值接近。     

碳纤维表面化学镀镍工艺研究

介绍了聚丙烯腈基碳纤维表面化学镀镍的工艺流程,前处理包括去胶、除油、粗化、中和、敏化、活化和还原.探讨了碳纤维的去胶方法,优化了化学镀镍的配方.研究了主盐、还原剂、pH和施镀时间对碳纤维增重率的影响.结果表明,在400℃下灼烧30 min,可去胶完全.硫酸镍质量浓度为30 g/L、次磷酸钠质量浓度为35 g/L、pH为4.5左右及施镀时间为lh时,所得碳纤维的增重率最大.     

Electrochemical composite formation of thiophene and N-methylpyrrole polymers on carbon fiber microelectrodes: Morphology,characterization by surface spectroscopy,and electrochemical impedance spectroscopy

Electrochemical composite thin film formation (∼0.6–0.7 μm) of thiophene and N-methylpyrrole on carbon fiber microelectrodes (diameter ∼7 μm) was carried out by cyclic voltammetry in order to understand and improve the surface properties and capacitance behaviour of carbon fibers. Carbon fiber microelectrodes were coated with polythiophene and N-methylpyrrole was electrografted onto the thiophene electrode. The electrocoated carbon fiber surface mophology was characterized by scanning electron microscopy and atomic force microscopy and by FTIR-reflectance spectroscopy for their composition. The effect of monomer concentration and scan number on electropolymerization has also been investigated. The impedance behaviour of composite electrodes was characterized by electrochemical impedance spectroscopy. The composite of polythiophene and poly-N-methylpyrrole exhibits better charge storage properties than polythiophene coated carbon fiber microelectrodes.     

Influence of thermo‐oxidative aging on vibration damping characteristics of conventional and graphene‐based carbon fiber fabric composites

The effect of thermo‐oxidative aging on the vibration damping characteristics of the conventional fabric composites reinforced by three‐dimensional (3D) and four‐directional (4Dir) braided preform and laminated plain woven fabric and the 3D‐4Dir braided graphene‐based carbon fiber composites was investigated. Specimens were isothermally aged at 140 °C for various periods of time up to 1,200 h. The results indicated that the thermo‐oxidative aging resulted in deterioration of the matrix and interface performance, in the form of chain scissions, weight loss, microcracks and interfacial debonding, which should be responsible for the decrease of nature frequency and the increase of damping coefficient of the composites. After aging for 1,200 h, the first nature frequency and first damping coefficient retention rates of 3D‐4Dir braided graphene‐coated carbon fiber/epoxy composite were 5.5% and 6.4% higher than those of laminated composite, respectively. One of the reasons was the integrated structure of 3D‐4Dir braided composite exposed lower fiber end area to air than that of laminated composite, leading to less interface oxidation. Another reason was that the graphene reinforced gradient interphase provided an effective shield against interface oxidation and restricted the movement of the different phase of the materials at the composites interface. This synergetic reinforcing effect of 3D‐4Dir braided structure and graphene reinforced hierarchical interface provides an easy and effective way to design and improve the thermo‐oxidative stability of carbon fiber reinforced polymer composites. POLYM. COMPOS., 37:2871–2883, 2016. © 2015 Society of Plastics Engineers     

Aluminum/carbon fiber hybrid composites

An effective, economic way of using carbon fiber is to combine it with a resin and another material, either a fiber or a metal, to produce a hybrid structure. Some of the properties of a hybrid beam made by attaching carbon composite to either side of an aluminum channel section are described here. The structure has considerable potential in the orthotics field; the aluminum core assists in the forming of, for instance, orthoses (calipers), modifies the failure characteristics of the carbon fiber composite, and eases the problem of jointing and adjustment of finished articles. Difficulties can arise when combining carbon composites and metals because of differences in thermal expansion behavior. To alleviate these effects a urethane modified epoxide resin matrix, which has very good adhesive properties, was employed. The work covers measurements of strength and modulus, evaluation of the aluminum/aluminum bond strength, and the flexural fatigue performance.     

Improving through-thickness conductivity of carbon fiber reinforced polymer using carbon nanotube/polyethylenimine at the interlaminar region

The through-thickness conductivity of carbon fiber reinforced polymer (CFRP) composite was increased by incorporating multiwalled carbon nanotubes in the interlaminar region. Carbon nanotubes (CNTs) were dispersed in a polyethylenimine (PEI) binder, which was then coated onto the carbon fiber fabric. Standard vacuum-assisted resin infusion process was applied to fabricate the composite laminates. This modification technique aims to enhance the electrical conductivity in through-thickness direction for the purpose of nondestructive testing, damage detection, and electromagnetic interference shielding. CNT concentrations ranging from 0 to 0.75 wt% were used and compared to pristine CFRP samples (reference). The through-thickness conductivity of the CFRP exhibited an improvement of up to 781% by adopting this technique. However, the dispersion of CNT in PEI led to a viscosity increase and poor wetting properties which resulted in the formation of voids/defects, poor adhesion (as shown in scanning electron micrographs) and the deterioration of the mechanical properties as manifested by interlaminar shear strength and dynamic mechanical analysis measurements.     

Characterization of the interphase in carbon fiber/polymer composites using a nanoscale dynamic mechanical imaging technique

The interphase of fiber reinforced polymer composites is a narrow region around the fiber, and the mechanical performance of a composite strongly depends on the properties of the interphase. The interphase of carbon fiber reinforced polymer composites (CFRPs) is difficult to quantitatively characterize because of its nanometer dimension. To solve this problem, we present a nanomechanical imaging technique for mapping the dynamic mechanical property around the interphase region in CFRPs, and for providing nanoscale information of the interfacial dimension. The experimental results show that this method can determine the width and topography of the interphase with nanoscale lateral resolution, based on the storage modulus profile on the cross section of the composite. The average interphase thicknesses of a T300 carbon fiber/epoxy resin composite and a T700 carbon fiber/bismaleimide resin composite are 118 nm and 163 nm, respectively, and the size of interphase is uneven in width and “river-like”, which is consistent with the surface topography of the carbon fibers. Furthermore, the effect of water-aging on the interphase of the T300/epoxy composite was analyzed using the in situ imaging technique. An increase in the interphase width and interface debonding were revealed, implying a degradation in the interphase region.