改性环氧树脂固体颗粒冲蚀磨损试验研究

摘要：采用气流挟沙喷射法对改性环氧树脂材料进行固体颗粒冲蚀磨损试验,考查冲蚀速度和角度对其冲蚀磨损的影响,并探讨了其冲蚀磨损机理,对比了相同冲蚀条件下几种材料冲蚀率的大小。实验结果表明,改性环氧树脂材料冲蚀率与冲蚀速度近似呈线性关系;在不同的冲蚀速度下,改性环氧树脂材料的冲蚀率在45°冲蚀时最大,表现出半塑性材料的冲蚀特征;在相同的冲蚀条件下,改性环氧树脂材料冲蚀率是对比材料(如M30砂浆、水泥石等)冲蚀率的1/16～1/4,适合用作强风沙流环境下混凝土桥梁墩身的防护材料;冲蚀形貌扫描电子显微镜照片表明,冲蚀能量的法向分量使材料表面产生裂纹和破碎,而其切向分量使材料表面产生切削。     

陶瓷材料冲蚀磨损的研究

冲蚀磨损是现代工业生产中常见的一种磨损磨损形式，陶瓷材料由于其所具有的一些固有特性而在冲蚀环境下的应用越来越广。本文探讨了影响陶瓷材料冲蚀行为的因素。讨论了环境参数（如冲角，冲蚀速度，冲蚀时间和温度），磨粒性能（如硬度，粒度和形状），靶材性能（如硬度，断裂韧性和显微组织结构）等对冲蚀的影响规律。     

环氧树脂涂层的耐冲蚀磨损性能

配制了3种环氧树脂涂层配方,测试其耐冲蚀磨损性能。结果发现,以纳米蒙脱土为填料、203#聚酰胺为固化剂的环氧树脂涂层的耐冲蚀磨损性能最佳:随着磨料粒度、磨料质量分数、试验机主轴转速的增大,冲蚀磨损率增加,攻角为45°时冲蚀磨损率最大,60°时最小;推荐最佳耐磨涂层的配方为:w(环氧树脂E-44):w(环氧树脂E一51):w(203#聚酰胺):w(纳米蒙脱土)为30:70:80:7。     

风沙环境下混凝土桥梁墩身固体颗粒冲蚀磨损及防护材料试验研究

采用气流挟沙喷射法对混凝土、改性环氧树脂及其复合材料进行冲蚀磨损实验,对比研究冲蚀参数对其冲蚀磨损的影响,并分析其冲蚀磨损机理.结果表明,C35混凝土和玻璃纤维环氧树脂复合材料冲蚀率与冲蚀平均速度近似呈线性关系,但对于混凝土,当冲蚀平均速度大于31 m/s时,曲线出现了转折,斜率变得更大;C35混凝土具有脆性材料的冲蚀行为,在90°冲蚀时冲蚀率最大,而改性环氧树脂及其复合材料具有半塑性材料的冲蚀行为,在45°冲蚀时冲蚀率最大;混凝土表面的冲蚀磨损机制为表面疲劳横向裂纹引起靶材流失,而其内部的冲蚀磨损机制为砂浆和粗骨料的选择性磨损;玻璃纤维环氧树脂复合材料的冲蚀磨损机制为环氧基体的微切削磨损、玻璃纤维和基体的剥离以及玻璃纤维的弯曲断裂.玻璃纤维环氧树脂复合材料的冲蚀率为同条件下C35混凝土冲蚀率的1/4～1/11,具有良好的抗冲蚀能力,是强风沙流地区混凝土桥梁墩身冲蚀磨损防护的理想材料.     

碳化硅陶瓷的冲蚀磨损机理

采用自主研发的冲蚀磨损试验机,以碳素钢为参照,对碳化硅陶瓷进行冲蚀磨损实验.通过控制冲蚀角度、冲蚀时间和粒子冲蚀速度,测定碳化硅陶瓷的冲蚀磨损量,并借助于SEM对冲蚀磨损后试样的显微结构进行观察.实验结果表明:碳化硅陶瓷体积冲蚀率随角度增大而增大,在90°下达到最大;碳化硅陶瓷的冲蚀磨损机理为:在小角度下主要以切削磨损为主,在大角度下主要以脆性断裂为主.     

高压管汇冲蚀磨损规律分析

面对当前的高压管汇冲蚀磨损理论,并没有对高压力载荷对冲蚀磨损产生的影响进行考虑。本文针对高压管汇冲蚀磨损规律做出了进一步探究,对研究高压管汇冲蚀磨损规律的现实意义、高压管汇冲蚀磨损规律的数值模拟、高压管汇冲蚀磨损数值模拟的结果给出了详细的分析。     

聚氨酯/TiN陶瓷复合材料冲蚀磨损特性研究

聚四氢呋喃醚二醇（PTMG）和甲苯二异氰酸酯（TDI）反应后，再与微米级TiN陶瓷粉末进行共混，制得耐磨蚀聚氨酯复合材料。通过扫描电镜观察了聚氨酯复合材料的磨损形貌，尝试解释了陶瓷颗粒增强聚氨酯弹性体的抗冲蚀磨损机理。实验表明：当-NCO质量分数为6．35％、TiN粉末质量分数为10％时，复合材料的耐磨性能最好，提高纯聚氨酯弹性体抗冲蚀磨损性能近3倍。     

纳米粘土增韧环氧树脂的研究

以蒙脱石为原料,通过HDTMAB改性制备纳米粘土,得到的最佳制备条件为:反应温度90℃,矿浆浓度5%,反应时间2h。在环氧树脂中加入5重量份纳米粘土,制得的纳米粘土/环氧树脂复合材料的冲击强度和弯曲强度,分别比纯环氧树脂提高303.2%和45.5%。实验证明纳米粘土对环氧树脂具有显著的增韧和增强效果。     

90°弯管冲蚀磨损的数值模拟研究

利用FLUENT软件中的DPM模型,对含少量固体的90°液体管道内的冲蚀磨损情况进行了数值计算,得到了90°弯管中冲蚀磨损最严重的部位,并且流体对弯管的冲蚀磨损速率随着弯管中流体速度的增大而呈线性增加,随着弯管中颗粒含量的增加而呈线性增加,且弯管的最佳弯曲半径为R=1.5D或R=2D。     

橡胶增韧环氧树脂的研究

以羧基丁腈橡胶、聚硫橡胶和羟基聚硅氧烷为增韧剂,以冲击强度、弯曲强度和拉伸剪切强度来评价环氧树脂的增韧效果。实验结果表明,加入增韧剂后的各配方韧性相对于对照组均有不同程度的提高;液态聚硫橡胶增韧的环氧树脂胶表现出良好的抗冲击性能和抗弯曲性能;羧基丁腈橡胶增韧的环氧树脂胶表现出良好的拉伸剪切性能。     

反应性聚碳酸酯/环氧树脂体系的形态与增韧性能

将胺化聚碳酸酯（a-PC)和环氧树脂（EP)以一定的比例混合,加热到120－160℃后加入熔化的二氨基二苯基甲烷,可制备固化的胺化聚碳酸酯增韧环氧树脂,结果表明,EP与a-PC形成了网络结构,且当a-PC质量分数为10％时,试样断裂韧性最大。     

热塑性聚酰亚胺增韧环氧树脂胶粘剂的研制

利用热塑性聚酰亚胺粉末增韧改性环氧树脂,得到了综合性能优异的胶粘剂体系,并对其凝胶化时间、接触角、表面能、疏水性、耐热性等各项性能进行了研究。     

橡胶弹性体增韧环氧树脂的研究进展

综述了环氧树脂增韧改性的研究现状,详细介绍了丁晴橡胶、丙烯酸酯橡胶和聚氨酯弹性体增韧环氧树脂的研究进展,展望了橡胶弹性体增韧环氧树脂的前号。     

On hybrid toughened DGEBA epoxy resins

Considerable improvements in the fracture resistance of epoxy resins have recently been achieved by adding either rubbery or rigid second phase dispersions, or both, to an epoxy matrix. These multiphase epoxy systems are particularly useful as high performance adhesives and as matrix materials in advanced composites. This paper describes the development of new toughened epoxy hybrids, which contain both rubbery and rigid dispersions. The latter dispersions were either zirconia particles, short alumina fibres or glassy-metal ribbons. Micromechanisms of toughening and failure processes in these new materials are identified and discussed in the light of microstructures.     

Bisphenol-A epoxy resin reinforced and toughened by hyperbranched epoxy resin

The study on toughening and reinforcing of bisphenol-A epoxy resin is one of important developmental direction in the field. This paper reports a one-pot synthesis of aromatic polyester hyperbranched epoxy resin HTDE-2, an effect of HTDE-2 content on the mechanical and thermal performance of the bisphenol-A (E51)/HTDE-2 hybrid resin in detail. Fourier transform infrared (FT-IR) spectrometer, scanning electronic microscopy (SEM), differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), dynamic mechanical thermal analysis (DMA) and molecular simulation technology are used to study the structure of HTDE-2, performance and toughening and reinforcing mechanism of the HTDE-2/E51 hybrid resin. It has been shown that the content of HTDE-2 has an important effect on the performance of the hybrid resin, and the performance of the HTDE-2/E51 blends has maximum with the increase in HTDE-2 content. The impact strength and fracture toughness of the hybrid resin with 9 wt-% HTDE-2 are almost 3.088 and 1.749 times of E51 performance respectively, furthermore, the tensile and flexural strength can also be enhanced about 20.7% and 14.2%, respectively. The glass transition temperature and thermal degradation temperature, however, are found to decrease to some extent. __________ Translated from Journal of South China University of Technology (Natural Science Edition), 2006: 34(9): 90–94 [译自: 华南理工大学学报 (自然科学版)]     

环氧大豆油低聚物增韧环氧树脂胶粘剂

合成了三种环氧大豆油低聚物作为室温和高温固化环氧树脂增韧剂,对其增韧环氧体系的粘接性能和力学性能进行了考察。试验结果表明,环氧树脂低聚物对固化体系的初期粘度等性能没有影响,对固化体系粘接性能和力学性能等有较大影响。与未改性的环氧树脂相比,由顺丁烯二酸酐扩链的环氧大豆油低聚物改性的环氧树脂剪切强度提高了56.64%。     

纳米技术在弹性体增韧环氧树脂中的应用

综述了弹性体与无机纳米粒子协同增韧改性环氧树脂以及纳米弹性体粒子增韧环氧树脂的应用进展,并且对纳米技术在弹性体增韧环氧树脂中的应用进行了展望。     

Mixed-mode fatigue behavior of degraded toughened epoxy adhesive joints

Open-faced asymmetric double cantilever beam (ADCB) specimens of toughened epoxy-aluminum adhesive joints were aged either in a constant humidity environment or a cyclically changing environment to study the mixed-mode fatigue behavior. Under constant humidity environments, the fatigue threshold strain energy release rate initially decreased with aging time until it reached a constant minimum value for long times. In contrast, the crack growth rates continued to increase with aging time. It is hypothesized that at crack growth rates close to threshold the fatigue behavior is governed by the epoxy matrix, whereas at relatively high crack growth rates the fatigue behavior is governed by the loss of the rubber toughening mechanism. Increasing the aging temperature accelerated the degradation of the joints leading to a reduction in the time to reach the constant minimum value and increased the crack growth rates.Under a cyclic aging environment with intermittent salt spray, neither the threshold strain energy release rate nor the crack growth rates degraded until four weeks of aging. The superior fatigue performance of these joints compared to joints aged in constant humidity environments was due to the lower water concentrations in the adhesive while aging. This conclusion was supported by moisture uptake measurements of the adhesive in deionised and salt water environments that showed simple Fickian behavior at room temperature and dual-Fickian behavior at higher temperature. The salt water environment produced osmotic pressure that decreased the moisture concentration in the second stage of diffusion.     

橡胶增韧环氧灌封料的研究

以液体羧基丁腈橡胶、液体聚硫橡胶为增韧剂制成环氧树脂灌封料,通过冲击强度、弯曲强度和拉伸剪切强度评价增韧环氧树脂灌封料的效果。实验结果表明,加入增韧剂的灌封料韧性与对照组相比均有不同程度的提高;液体聚硫橡胶增韧的环氧树脂灌封料表现出较好的抗冲击性能和抗弯曲性能;液体羧基丁腈橡胶增韧的环氧树脂灌封料表现出较好的拉伸剪切性能。