疲劳/蠕变复合作用下聚苯乙烯的交互损伤研究

STUDY OF THE MUTUAL DAMAGE OF POLYSTYRENE BOTH IN FATIGUE AND CREEP

探讨了在疲劳 /蠕变复合作用下聚苯乙烯的损伤交互作用。结果表明 ,在疲劳 /蠕变复合作用下聚苯乙烯存在疲劳和蠕变的交互损伤 ,其断裂寿命比纯疲劳或纯蠕变的断裂寿命低 ;断裂机制是疲劳循环载荷松动和活化了分子链或链段 ,从而促进蠕变运动和断裂。并且 ,疲劳

The mutual damage of polystyrene both in fatigue and creep were studied. The results show that the mutual damage of polystyrene both in fatigue and creep exists. The breaking life is less than one of pure fatigue or creep. The breaking mechanism is that fatigue cycle load causes molecular chains or chain segments to be elongated and shortened cyclically ;and then the molecular chains or chain segments which movements were resisted in single directional external force are loosened and activated. Therefore it encourages creep movement and fracture. The degree of mutual damages both in fatigue and creep is closely related to temperature. The degree of mutual damages at lower temperature is more large than that at higher temperature. The breaking life is shorter with higher temperature because the individual damage of pure fatigue or creep increases.