铺层角度偏差对曲面复合材料结构固化变形的影响分析

本文阐述了铺层角度偏差对某变厚度曲面结构复合材料固化变形的影响。对铺层角度偏差的来源进行了归纳,采用考虑热膨胀和固化收缩的固化变形计算模型,对该变厚度的复合材料曲面层合板结构的固化变形进行了计算,计算结果与试验结果较为吻合,表明了计算模型的准确性。采用均匀试验设计方法,得到了该曲面结构铺层角度偏差在5°以内变化时的实验方案,对实验设计的计算结果进行了回归分析,结果显示,对于该曲面复合材料结构,总体上铺层角度偏差对固化变形的影响不大,相对的,-45°的铺层偏差对固化变形的影响较大,90°的铺层偏差对固化变形的影响较小。     

无机复合超细阻燃填料的表面改性

对适宜配比的硅镁铝粉-氢氧化镁复合阻燃填料进行了表面改性方法和配方研究,考察改性方法、改性剂配方、改性剂用量等对复合阻燃填料填充效果的影响。采用红外光谱和扫描电镜对复合阻燃填料进行测试分析。结果表明:湿法改性效果好于干法,最佳的表面改性剂为硅烷SCA313和脂肪酸的复配,适宜的用量为w(SCA313)=0.6%、w(脂肪酸)=1.0%;改性剂以化学吸附方式协同包覆于填料表面。     

混合式定量加料过程的PID-模糊控制

在论述混合式定量加料原理的基础上，介绍了PID-模糊控制在混合式定量加料中的应用，研究了一个具体的PID-模糊控制设计方法，在实验的基础上得出相关的参数，用Matlab仿真结果表明PID-模糊控制提高了称重过程加料精度，并有效地改善控制系统的稳定性和可控性。     

Machinablity of Hybrid Natural Fiber Composite with and without Filler as Reinforcement

The filler materials are reinforced along with natural fibers in the composite to improve the quality and property of the component materials based on the requirements and its applications. In this paper, hybrid natural fiber composites were developed with and without filler materials as reinforcement. The developed hybrid natural fiber composites are machined using abrasive water jet cutting process with three different cutting parameters. The influences of cutting parameters are evaluated with respect to the kerf wall inclination, material removal rate, and surface roughness. The surface morphology was also studied to infer the basic mechanism involved during composite machining. The hybrid fiber composite with filler has proved that it can produce good engineering component without delamination and fiber pullouts during machining.     

Effects of Al2O3—Particulate—Contained Composite Filler Materials on the Shear Strength of Slumina Joints

Al2O3/Al2O3 joints were brazed with a new kind of filler materials,which were formed by adding Al2O3 particulates into Ag-Cu-Ti active filler metal.The results showed that the material parameters (the Ti content,Al2O3 particulate volume fraction) of the composite filler materials affected the shear strength of brazed joints.When the Ti content was 2 wt pct in the filler metal, the shear strength of brazing joints decreased with the increasing the volume ratio of Al2O3 particulate .When the Ti content was 3 wt pct in the filler metal, the shear strength of joints increased from 93.75 MPa(Al2O3 pOvol pct) to 135.32 MPa(Al2O3 p15 vol.pct).     

阻尼复合材料舵板减振降噪试验研究

介绍了阻尼复合材料舵板的模拟试验情况,对阻尼复合材料舵板和金属舵板进行了水下振动和振动声辐射特性的对比试验分析,结果显示,在100Hz到5kHz范围内,水下辐射噪声前者比后者平均降低约7dB,表明该阻尼复合材料用于舰船的某些典型振动构件具有广阔前景。     

Effects of Al_2O_3-Particulate-Contained Composite Filler Materials on the Shear Strength Alumina Joints

Al2O3l2O3 joints were brazed with a new kind of filler materials, which were formed by adding AI203 particulates into Ag-Cu-Ti active filler metal. The results showed that the material parameters (the Ti content, Al2O3 particulate volume fraction) of the composite filler materials affected the shear strength of brazed joints. When the Ti content was 2 wt pct in the filler metal, the shear strength of brazing joints decreased with the increasing the volume ratio of Al2O3 particulate. When the Ti content was 3 wt pct in the filler metal, the shear strength of joints increased from 93.75 MPa(AI203p 0 vol. pct) to 135.32 MPa(AI203p 15 vol. pct).     

一种新型湿式金属填料过滤性能的实验研究

介绍了湿式与金属填料叠加的除尘器的结构、综合除尘机理及其它有效的功能,可有效克服传统纤维过滤器的不足。实验测试了在不同气流流速下和不同喷淋密度下除尘器的过滤性能,实验结果表明当风速1.2 m/s、喷淋密度1.0 m3/h时,湿式金属填料过滤系统除尘效率可到75%,可应用于集中式中央空调或通风系统中。     

填料类型对 PVC 密封垫蒸发残渣的影响

实验研究了填料类型、粒径大小和用量对 PVC 密封垫蒸发残渣卫生性能的影响。 结果表明:4 种填料均可用于水性和酒性产品包装的密封材料中,针状填料 T4 适宜于酸性产品密封料,油性产品密封料除优选填料外,还需对增塑剂进行筛选;填料目数越小,蒸发残渣越大,在可生产的黏度范围,可增加填料用量。     

Effect of Processing on Precision of Composite Panels

As the demand for precision composite parts increases, understanding the effects of processing parameters on composite precision is needed. This study is devoted to observing the warping tendency of angles and investigating the effects of the part thickness, tool material, and stacking orientation on the precision of angled composite parts. Composite parts with both concave and convex angles were fabricated with various thickness, tool material, and stacking orientation. It was found that composite angled parts always warped inward. As the part angle decreased, the warp angle decreased. The resin volume fraction gradient induced a further inward warping tendency at convex angles. Rigidity improvement achieved by increasing the thickness overcame this resin gradient effect. The precision at convex angles was, thus, improved. However, the precision at concave angles worsened with increasing part thickness. The tool material was found to significantly affect the part precision at both concave and convex angles. Angled parts fabricated in molds made of advanced composite tools yielded much better angle precision than that fabricated in mold made of aluminum tools. As far as the stacking orientation was concerned, the best precision at a 135° convex angle was achieved with a stacking orientation of [0/90/0/90/0/90/90/0], whereas at a 90° concave angle the best precision was achieved with [90/0]_4Tfor a laminate of 8 plies. A stacking sequence with a [0/90] orientation was found to cause upward warping. This could be used to counterbalance other inherent warping tendencies.     

Optimization of a New Filler/Binder for Direct Compression Using Central Composite Design

Abstract

An experimental design, the Central Composite, was used for the optimization of a new filler/binder (Xylitab 200®) for direct compression, with aspirin as the model drug. The design consists of four independent variables filler/binder, drug, disintegrant, and compression force) in varying amounts, and with crushing strength, friability, weight variation, disintegration time, and dissolution rate as response variables. Multiple regression in the form of a second-order polynomial was used to determine meaningful relationships. In this study, the amounts of compression force and disintegrant played an important role in controlling the response variables.     

Optimization of a New Filler/Binder for Direct Compression Using Central Composite Design

An experimental design, the Central Composite, was used for the optimization of a new filler/binder (Xylitab 200®) for direct compression, with aspirin as the model drug. The design consists of four independent variables filler/binder, drug, disintegrant, and compression force) in varying amounts, and with crushing strength, friability, weight variation, disintegration time, and dissolution rate as response variables. Multiple regression in the form of a second-order polynomial was used to determine meaningful relationships. In this study, the amounts of compression force and disintegrant played an important role in controlling the response variables.     

双辉等离子涂层对机械曲轴耐磨耐蚀性能的影响

采用双辉等离子技术在机械曲轴表面制备了SiC/Ta复合涂层,研究了合成温度对复合涂层显微形貌、物相组成、耐磨和耐腐蚀性能的影响。结果表明,当合成温度从750上升至900℃时,复合涂层表面形貌由花纹状逐渐演变成细小颗粒团簇状,截面形貌中可见不同合成温度下复合涂层厚度和内部质量存在一定差异,不同合成温度的复合涂层中都出现了SiC、Ta、Ta₂C和TaC衍射峰。机械曲轴基体的摩擦系数都高于不同合成温度下的复合涂层,合成温度800℃时复合涂层的摩擦系数最小且最为稳定;随着合成温度升高,磨痕深度、磨痕宽度、磨损体积和比磨损率都呈现先减小后增大的特征,在合成温度为800℃时磨损体积和比磨损率最小;极化曲线和电化学阻抗谱测试结果保持一致,即复合涂层的耐蚀性能都优于基体,且合成温度为800℃时复合涂层的耐蚀性能最好;机械曲轴表面适宜的复合涂层合成温度为800℃,此时复合涂层具有最佳的耐蚀和耐磨性能。     

200型捻股机噪声分析与控制

200型捻股机的噪声源主要在捻股机的简体和齿轮箱体，提高简体和齿轮的制造精度，合适选择轴承类型、精度，正确调整轴承的间隙和预紧力，可有效地控制200型捻股机的噪声。     

SiC填料对光伏封装用EVA导热复合胶膜的影响

目的探讨乙烯-醋酸乙烯酯共聚物(EVA)胶膜中加入晶须碳化硅(SiC)无机填料后,对EVA胶膜交联度、力学性能及导热性能的影响。方法通过将晶须SiC无机填料导入EVA,使得在整个体系内呈连续相的有机大分子与呈分散相的无机填料共混成一体,再通过挤出流延成形得到厚度均一的胶膜。结果随着晶须SiC含量的增加,EVA复合胶膜的抗拉强度和断裂伸长率均有所下降。交联度随着SiC含量的增加而略微增大,最终达到平衡,剥离强度先增大后减小。使用不同的偶联剂对SiC表面进行处理,EVA导热复合胶膜导热性能存在差异。使用同一种偶联剂对SiC表面进行处理,SiC粒径尺寸的差异同样对EVA导热复合胶膜导热性能存在差异。结论添加晶须SiC的尺寸规格、添加量、表面处理情况对EVA导热复合胶膜的力学性能、交联度影响较大。     

硫化剂含量及填料类型对三元乙丙橡胶性能的影响

为了获得综合性能更加优异的橡胶密封材料,文中分别研究了硫化剂含量及填料类型对三元乙丙橡胶交联密度、拉伸性能、硬度及压缩永久变形性能的影响。结果表明,未填充橡胶中硫化剂含量增多,体系交联密度增加,拉伸强度及断裂伸长率降低,硬度增加。较高的交联密度有利于降低压缩永久变形,但过度交联使材料性能下降。填充橡胶的交联密度、拉伸强度及硬度高于未填充橡胶。白炭黑填充体系的交联密度小于炭黑填充体系,但拉伸强度及硬度都大于炭黑填充体系。填充量一定时,炭黑填充体系的压缩永久变形小于白炭黑填充体系,疏水型气相法白炭黑填充体系的压缩永久变形小于普通气相法白炭黑填充体系。     

粉粒状物料混合式定量充填技术研究

在分析了目前粉粒状物料定量充填技术现状的基础上,论述了粉粒状物料混合式定量充填技术原理,分析了混合式定量充填性能,并提出进一步提高性能的措施,为粉粒状物料定量包装提供了一种新方法。     

新型功能性聚氨酯复合包装板材弯曲和压缩性能的研究

介绍了一种新研制的功能性聚氨酯夹层复合包装板材.为找出最佳的工艺条件,对板型结构和原料配方进行了实验研究,分析了聚氨酯泡沫塑料和聚氨酯复合包装板材的抗弯弹性模量、抗压强度这两项主要力学指标.由材性分析得出:可通过采用不同力学强度的面板材料压制所需力学强度的聚氨酯复合板材,若采用的面板材料力学强度较差,可适当提高泡沫塑料的密度或者添加夹层来提高力学强度.     

Effect of Diamond Additions on Wettability and Distribution of SnAgCu Composite Solder

Diamond/SnAgCu composite solder bumps were prepared on Cu pad by mechanically incorporating diamond particles into Sn3.0Ag0.5Cu(SAC) solder powders,mixing with flux and reflowing at 260 ℃ for 60 s.The spreading areas of composite solder were calculated and the distributions of copper-coated diamonds were characterized.When diamond additions were below 3 wt%,the spreading area decreased with diamond additions,and the diamonds distributed mainly at the interface between solder and Cu pad;however,when additions were beyond 4 wt%,the discharge of diamond particle occurred,and the spreading area increased due to the reduction of surface energy.