橡胶增韧环氧树脂的低周疲劳行为  

Low cycle fatigue behavior of rubber toughened epoxy resins

作　　者：孙振华[1,2] 罗辉阳[1,2] 赵世琦 

机构地区：[1]清华大学工程力学系 [2]清华大学化学工程系

出　　处：《清华大学学报（自然科学版）》1999年第4期17-20,共4页Journal of Tsinghua University(Science and Technology)

摘　　要：为了揭示橡胶增韧环氧树脂的低周疲劳行为，分别对１５份的端羧基丁腈橡胶（ＣＴＢＮ）增韧、１５份的奇士增韧剂增韧的酸酐环氧树脂和纯酸酐环氧树脂的低周疲劳寿命、循环应力应变行为和疲劳断口用扫描电镜（ＳＥＭ）进行了研究。橡胶增韧环氧树脂的低周疲劳行为得到明显改善，其疲劳寿命可提高３～２０倍；其循环应力应变滞回环稳定不变；疲劳断口有应力发白现象；应力发白区为疲劳裂纹形核和萌生区，其寿命占疲劳总寿命的大部分；ＳＥＭ观察显示出其两个主要的增韧机理——基体剪切屈服和空穴塑性体积增长，控制着疲劳裂纹的形核和萌生。The low cycle fatigue (LCF) testing of 15 percent CTBN (carboxyl terminated butadiene acrylonitrile), 15 percent Qishi toughening agent toughened anhydride cured epoxy resins(EP) and pure anhydride cured EP was performed, respectively. The LCF behavior of toughened and pure EP uncover that its S N curves are satisfied with Basquing laws and the LCF behavior is obviously improved due to the toughening, and its fatigue life is (4￣21) times that of pure epoxy. The cycle stress strain behavior of toughened EP has small and stable hysteresis loops. The stress whitening can be clearly seen on the fatigue fracture surface and its region is the initiation and nucleation of fatigue crack which is the main part of total fatigue life. The sweep electron microscope (SEM) observation reveals that two main toughening mechanisms localized shear yielding in epoxy matrix and void plastics growth dominate the initiation and nucleation.

关 键 词：环氧树脂 橡胶 增韧 低周疲劳 增韧机理 

分 类 号：TQ334.9[化学工程—橡胶工业] TQ323.5