在40℃和80℃环境中,分别对Bayer-PC、Japan-PC、Korea-PC三种聚碳酸酯缺口冲击试样进行了热空气老化和热水老化实验研究。在0～400h老化时间内,研究了这三种PC的热空气老化和热水老化对冲击强度和断面形貌的影响,讨论了PC热空气老化和热水老化机理。结果表明:老化前,Japan-PC、Korea-PC和Bayer-PC冲击强度分别为95kJ/m2、83kJ/m2和55kJ/m2;在40℃和80℃热空气老化后,三种PC冲击强度均有所下降,其中80℃热空气老化引起的降幅最大,热空气老化400h后的冲击强度顺序为Japan-PCKorea-PCBayer-PC,在40℃热水老化后,三种PC的冲击强度几乎不受老化时间影响;在80℃热水老化后,三种PC冲击强度均有所下降,其中Bayer-PC降幅最小,Japan-PC次之,Korea-PC最大,但PC的平衡冲击强度大小与热空气老化的情况相同。由扫描电镜对冲击断面形貌观察可知,未老化的三种PC均以剪切屈服破坏机理为主,老化后的三种PC主要以银纹集中破坏机理为主。

Hot air aging and hot water aging (at 40℃ and 80℃, 0～400h) of notched impact samples of Bayer-PC (3103), Japan-PC (K1300) and Korea-PC (3027U S) have been investigated. The effect of hot air aging and hot water aging of-PCs on the impact strength and fracture surface appearance was studied. The hot air aging and hot water aging mechanism was discussed. The experiment show that before aging, the impact strengths of-PCs are 95kJ/m2, 83kJ/m2, 55kJ/m2. After hot air aging at 40℃ and 80℃, the impact strengths of-PCs were reduced, and the degree of decrease at 80℃ was great, the order after hot air aging (400h) is: Japan-PCKorea-PCBayer-PC, that is to say, the impact strength of Japan-PC is the best. The influence of hot water aging at 40℃ on the impact strengths of-PCs is the least. The impact strengths of-PCs were reduced after hot water aging at 80℃, the degree of decrease of Korea-PC is the largest, that of Bayer-PC is the least, however, the equilibrium impact strength is same as that of hot air aging. According to SEM photographs of fracture surface appearance, the main fracture mechanism of unaged-PCs is shear yielding,and that of aged-PCs is caving.