高强度系列夹层玻璃的研制

采用粘结法、热压法和蒸压法在实验室制作了夹层玻璃小试样。通过测试试样的冲击强度,分析了玻璃与聚碳酸脂(PC)胶片的组合结构对夹层玻璃强度的影响,比较了热压法与粘结法对树脂中间层与玻璃之间的粘附状况。实验结果为今后在生产中使用国产树脂胶片,提供了相应的技术路线。     

界面性质对夹层玻璃粘结性能的影响

鉴于夹层玻璃是由两种或多种透明固体基材通过热压工艺复合在一起，笔者就材料界面性质对粘结性能的影响进行了深入的研究。本文详细论述了固体材料表面能的组成部分，界面张力的计算方法，给出了通过接触角测试固体各表面能分量的方法。通过计算机语言，可以编制计算固体材料各种表面分量的程序，使固体材料表面能的获取简易、可行。对于本文研究的夹层玻璃，研究发现，粘结界面极性分量匹配性对粘结强度的影响占主要地位。以此为基础，对非化学反应为基础(如热熔成型)的粘结，提出了判断低表面能基材与不同粘结剂粘结性能好坏的非破坏方法。     

过盈粘结试验及应用

近年来,随着粘结剂的推广应用,圆柱形粘结头已广泛应用于联结管道、轴套类零件。实践证明圆柱形粘结头比其它粘结头,例如平面粘结头等具有更高的粘结强度。这是由于大多数的粘结剂总是抗剪强度相对高一些,因此粘结头总是尽可能设计成承受剪切力为好,而在圆柱形粘结头中,在承受拉     

夹层玻璃的特性与应用

夹层玻璃是一种性能优良的安全玻璃 ,它是由两片或两片以上的玻璃 ,中间夹以聚乙烯醇缩丁醛( PVB)胶片 ,在一定的温度和压力下粘接而成的。它具有耐光、耐热、抗冲击强度高等特点 ,广泛应用于汽车、火车、轮船、飞机等运输工具及建筑方面。与传统的普通玻璃相比 ,夹层玻璃在安全、保安防护、隔音及防辐射等方面有着不可比拟的优良性能。1　安全特性当前 ,建筑对于采光的要求越来越高 ,采光面积占建筑物围护的面积比例越来越大 ,普通玻璃远远不能满足安全防护的要求。而夹层玻璃在受到超强度意外撞击被破坏时 ,玻璃的碎片被牢牢地粘结在聚…     

浅谈玻璃的热弯工艺及常见问题的分析

热弯夹层玻璃作为安全玻璃的一种重要的形式,应用领域非常广泛,这种产品由两层或多层的热弯玻璃经PVB胶片粘结而成,具有很高的强度和韧性,抗碰撞能力强,安全可靠,透明度高,一旦破碎,夹层玻璃承受高速冲击的强度高于钢化玻璃,玻璃破碎后无碎片飞溅,玻璃的碎片仍能粘接在PVB片上。鉴于此种特点,热弯夹层玻璃几乎应用于所有汽车玻璃的前风挡领域,同时也广泛应用于建筑门窗幕墙、博物馆、陈列厅等相关领域。对热弯工艺中常见的问题进行分析,并给出相应的解决方法。     

一种太阳能光伏发电夹层玻璃

本发明提供一种能够发电的夹层玻璃一太阳能光伏发电夹层玻璃，其结构依次为：玻璃板／粘接层／太阳能电池组／粘结层／玻璃板。太阳能电池组包含至少含有一块太阳能电池板，以及太阳电池板的正负极引出线，正负极引出线从夹层玻璃中引出，从玻璃的边部引出，或者是从玻璃中间的钻孔处引出。玻璃板可以是浮法玻璃、平板玻璃、压花玻璃、钢化玻璃、低辐射镀膜玻璃或热反射镀膜玻璃。粘结层，     

玻璃抗静态均布水压的研究

钢化玻璃和夹层玻璃是两种常见的玻璃深加工产品，因其强度高、安全性能好，在建筑幕墙、室内外装饰装潢领域得到了广泛的应用。然而长期以来由于缺乏必要的测试手段和相关的文件，玻璃生产商一直对已生产的钢化玻璃和夹层玻璃的力学性能以及相应指标缺乏了解，在有关力学数据的积累方面工作也做得很少，无法为客户提供必要的技术指导。     

建筑涂料的附着力要求多大比较合适?

根据中日两国对合成树脂乳液砂壁状建筑涂料和复层建筑涂料的标准要求进行分析,结合生产实际,得出建筑涂料的附着力要求,即:建筑涂料涂膜的粘结强度0.04 MPa是够用的;粘结强度的有效数字1位就够了;涂料的粘结强度要求一般不应高于腻子的粘结强度要求;建筑涂料涂膜的粘结强度不是建筑涂料的短板,而是长板。     

掺入塑钢纤维的轻骨料混凝土与钢筋间的力学性能研究

为了分析塑钢轻质骨料加入到混凝土中的力学以及粘结性能,基于试验研究并分析了影响混凝土试件力学以及粘结性能的影响因素,实验结果表明：加入不同比例的塑钢纤维混凝土试件的力学以及粘结性能均表现出了不同的变化特性,混凝土及砂浆的用水量、砂率的不同,会导致塑钢纤维对混凝土的增强效果差异较大;素混凝土的强度较高时,混凝土试件的粘结性能越高,并且其钢筋产生的位移大大降低;加入塑钢纤维的混凝土试件的力学以及粘结性能均会随着轻质骨料筒压的降低而降低。     

CFRP层合板冲击后压缩失效分析数值模拟

复合材料层合板的损伤容限是复合材料结构设计的关键因素。针对碳纤维增强复合材料(CFRP)层合板低速冲击损伤和压缩破坏问题,本文基于连续损伤力学和粘结单元模型,在ABAQUS中对两种不同冲击能量下的层合板进行了低速冲击和冲击后压缩仿真分析,并对层内和层间损伤进行了研究,分析了层合板的冲击损伤与压缩失效行为,通过与试验结果进行对比,验证了该模型的有效性。研究结果表明:冲击损伤对层合板的剩余压缩强度有着重要影响,试件的破坏开始于冲击损伤区域,并逐渐扩展到层合板的边缘,压缩力快速下降,层合板最终失效。     

DNAN力学性能分析

利用Materials Studio软件计算了DNAN和TNT晶体在常温(25℃)、常压下(105Pa)的弹性模量,预估了二者受力过程中塑性变形能力的差异;通过纳米压痕试验测试了DNAN和TNT的弹性模量及塑性变形能力;采用力学性能试验机测试了其抗压性能、抗拉性能、抗剪性能,并结合分子间作用力对强度差异的原因进行了分析。结果表明,DNAN的抗压强度为5.96MPa,抗拉强度为2.57MPa,抗剪强度为0.34MPa;TNT的抗压强度为15.57MPa,抗拉强度为2.35MPa,抗剪强度为1.8MPa;DNAN和TNT在受力过程中的弹性形变均为200nm,DNAN的塑性形变为450nm,TNT的塑性形变为1 200nm,DNAN相比于TNT更容易发生脆性断裂。     

BFRP筋轴心受压力学性能试验研究

为详细考察玄武岩纤维增强复合筋(BFRP)的轴心受压力学性能,设计制作了36个受压试件,测试BFRP筋的受压破坏模式、抗压强度、压缩弹性模量、压缩变形率,研究直径、长细比、破坏模式对BFRP筋受压力学性能的影响.试验结果表明,BFRP筋的受压破坏模式分为剪切、胀裂、失稳三种,以剪切破坏为主;受压应力—应变关系为线弹性,...     

Synergistic effect of glass fibre and Al powder on the mechanical properties of glass-ceramics

To explore the synergistic effect of glass fibre and Al powder on the mechanical properties of glass-ceramics, blast furnace slag was chosen as the main material, and glass fibre and Al powder as reinforcement materials. The phase compositions, microstructures, compressive properties, and apparent density of the glass-ceramics with varying quantities of glass fibre and Al powder were investigated. The experimental results indicated that Al powder could exist as a simple substance in glass-ceramics and form a dense net coating on the surface of blast furnace slag to improve the plasticity of the glass-ceramic. The glass fibre had better reinforcement effect than Al powder because of its extremely high mechanical strength. The plasticity of glass-ceramics, however, severely decreased; the glass-ceramics exhibited brittle failure during compression. A slight increase in the content of CaSi₂ and SiO₂ in the glass-ceramics was closely related to the addition of glass fibre. Considering safety and economy, glass-ceramics with 6% Al and 14% glass fibre (S4) have the best mechanical properties. The compressive strength, strain at maximum force, and apparent density were 40?MPa, 19% and 1.974?g/cm³, respectively.     

Design,development, and implementation of test methods for determination of through thickness properties of laminated composites

Abstract

Test methods for the measurement of through thickness elastic and strength characteristics of laminated composites in tension, compression, and shear have been investigated. Each method studied involved finite element analysis and practical testing on unidirectional carbon–epoxy laminated specimens. Tensile and compressive methods involved the direct loading of a parallel sided block for determination of elastic constants and a waisted specimen with square cross-section for the measurement of elastic constants and strength. Experimental results validated the numerical studies. The shear method consisted of a specimen bonded between steel plates, which were loaded in compression, inducing shear stresses in the specimen. Two specimen designs were developed. The first, for measurement of shear moduli only, was a parallel sided block. Specimen length and thickness were optimised for two fibre directions. The second design, for measurement of shear strengths, was a waisted specimen sandwiched between two epoxy blocks and subjected to a combination of shear and transverse compressive loading. Tests confirmed the validity of the shear moduli measurements. However, it was found that a pure shear failure mode was not achievable. Failure always occurred by a combination of shear and transverse tension.     

Determination of mechanical properties of glass‐epoxy composites in high temperatures

The objective of this study is to determine the tensile, compressive, and shear properties of unidirectional glass/epoxy composite plates under room (∼20°C) and high (40, 60, 80, and 100°C) temperatures. Mechanical properties were determined according to the ASTM standards. A hot lamination press was used for fabrication of composite plates. For curing process, laminated plates were retained at a constant pressure (250 kPa) and 120°C during 2 h. And then, composite plate is cooled to room temperature at the same pressure. The fiber volume fraction of laminated composite plate is measured as 65%. Experimental results show that the mechanical properties (except for the transverse tensile strength) of glass/epoxy composites are reduced by increasing temperature. POLYM. COMPOS., 2009. © 2008 Society of Plastics Engineers     

废旧线路板粉料作为BMC填料的正交试验研究

将废旧线路板回收处理过程中得到的粉料作为填料,采用模压成型的方法制备成BMC（预制团状模塑料）复合材料。通过正交试验确定BMC材料中不饱和聚酯树脂、短切玻纤和废旧线路板粉料的最优配比,同时得到树脂、粉料及玻纤加入量对BMC材料性能的影响。结果表明：当加入30份的短切玻纤、45份的废旧线路板粉料和30份的不饱和聚酯树脂时,制备的材料综合性能达到最优,弯曲强度和压缩强度可达63.8MPa、101.5MPa。     

Comparison of tensile and compressive characteristics of intra/interply hybrid laminates reinforced high‐density flexible foam composites

The current study focused on fabrication and mechanical evaluation of intra/interply hybrid laminates – reinforced high‐density flexible foam composites. The effects of composite thickness and expansion factor on the tensile and compressive characterization of the hybrid ‐ laminated composites were experimentally investigated. Double face sheets were made of high‐strength intra/interply hybrid laminates containing recycled Kevlar nonwovens and glass woven fabric. The results revealed that the hybrid laminates face sheet apparently promoted the tensile strength and tear resistance of the high ‐ density flexible polyurethane foam. Tearing resistance in perpendicular direction exceeded more than twice the value in parallel direction. In terms of dynamic cushioning properties, cushioning force increased with the increase in composite thickness and the decrease in expansion factor , whereas the cushioning capacity loss, however, showed a different trend with the variation of the parameters. Most samples buffered more than 95% incident force under dynamic loading. Composite thickness and expansion factor exhibited significant influence on compression and indentation properties, including hardness, initial hardness factor , and indentation modulus. Except the composites with 10 mm thickness, the intra/interply hybrid laminated composites exhibited hysteresis loss of indentation force deflection ranging from approximately 30 to 38%, which was due to the fiber and thermal bonding point failure of hybrid laminates as unrecoverable damage. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41438.     

湿度对水化硅酸钙力学性能影响的分子动力学模拟

水化硅酸钙(C-S-H)是水泥水化产物中最重要的组成成分,是水泥基材料的主要胶凝相。C-S-H层间水对其纳米结构和力学性能会产生显著影响。利用分子动力学研究了不同湿度C-S-H在结构和力学性能方面的差异。通过原子径向分布函数和浓度分布、弹性常数以及应力应变关系分析了湿度对C-S-H结构和弹性性质以及拉伸、压缩、剪切力学性能和变形性能的影响。结果表明:湿度增加会导致C-S-H中Si、Ca原子近程范围内的O原子集聚增多,还会导致C-S-H层间距离增大,分层更加明显,同时会降低C-S-H的弹性性质;湿度的增加会降低C-S-H拉伸、压缩、剪切力学性能和变形性能;湿度对抗拉与抗剪强度影响较大,对抗压强度影响较小,对拉伸时的变形性能影响最大,对压缩时的变形性能影响最小。     

固化压力对夹层结构力学性能的影响

通过测试不同固化压力下的Nomex蜂窝夹层结构的力学性能，讨论了固化压力对蜂窝夹层结构性能的影响。结果表明，在固化压力0．2－0．5MPa下，夹层结构的平拉强度、平压强度、剪切强度无明显变化，而侧压强度与弯曲刚度则随压力的增大而发生明显的变化。     

Glass bubble reinforced polyurethane foams with high mechanical strength for cryogenic temperature insulation

In this study, glass bubble (GB) is added to polyurethane (PU) foams at different weight ratios—0, 0.25, 0.5, 0.75, and 1 wt% —to investigate the changes in the mechanical and thermal properties of the foam. By conducting several tests and measurements, the density, cell morphology, compressive strength, and thermal conductivity of the foam are studied. In particular, the effect of GB additives is examined by conducting compression tests at various temperatures (−163, −100, −40, and 20°C). Scanning electron microscopy and X-ray microscope reveal that the foams exhibit higher stability below 0.5 wt%, which improves the thermal performance. On the other hand, the compressive strength of the foams increases for all weight ratios of GB, and it increases sharply at 0.75 wt%. In addition, the chemical interactions and the dispersion of additives in the PU matrix are investigated through Fourier transform infrared and X-ray diffractions analysis. It is found that the synthesis of PU foams with GB nanoparticles is an efficient method for improving the mechanical properties and insulation performance of the foam for LNG insulation technology.