摘要
考察了不同层数的环氧树脂/聚氨酯(EP/PU)梯度聚合物弯曲性能,采用有限元法分析了材料在弯曲状态下的应力分布,从理论上解释了EP/PU梯度材料弯曲性能的试验结果,并与相同组成的均质材料进行了比较。研究发现:EP/PU梯度材料的弯曲强度和模量随梯度层数的增加而增加,当梯度层数超过5层以后,EP/PU梯度材料的弯曲强度高于相同组成的均质材料。有限元分析结果表明:在EP/PU梯度材料中,应力的分布与各层材料承受的强度相匹配,即应力大的部位材料的强度也越大。梯度层越多,各层之间强度变化越小,应力变化越为缓和,且应力分布与材料强度之间匹配越好,在受外力时,材料断裂强度越高。梯度材料中应力分布方式的理论计算结果很好的解释了实测的各种梯度材料强度变化规律。
The flexural properties of epoxy resin/polyurethane （EP/PU） ladder polymer with different number of layers were studied. The stress distribution of the material at bending state was analyzed by means of finite element analysis （FEA） , and the results of the flexural test of the material were explained theoretically and compared with those of the homogeneous material composed of same composition. The results showed the flexural strength and modulus of EP/PU ladder materials increased with the increase of the number of the layers. When the layer number was more than 5, the flexural strength of the EP/PU ladder material was higher than that of the homogenous EP/PU system. The results of FEA analysis proved in the EP/PU ladder material the stress distribution in different layer was proportion to its modulus and strength, namely the flexural strength on the layer with higher modulus and strength was greater. The more the number of the layers, the smaller the change of the strength, and when the change of the modulus became smaller, the distribution of the stress of the layer matched with its strength better, resulted in high breaking strength on external force. The determined changing rule of the ladder material was Well explained by the theoretical calculation of the distribution of the stress in the ladder material.
出处
《塑料工业》
CAS
CSCD
北大核心
2009年第1期56-59,共4页
China Plastics Industry
