对芳纶纤维增强聚合物(AFRP)片材、碳纤维增强聚合物(CFRP)片材以及配套的环氧胶黏剂在60、80、100、120、140次冻融循环后的力学性能进行试验研究,并对两种片材的抗冻融性能进行对比.试验结果表明:冻融循环后,AFRP片材拉伸性能的变化幅度总体上大于CFRP片材,展现出相对更弱的抗冻融性能;冻融循环140次后AFRP片材的抗拉强度和弹性模量分别较未冻融时降低8.2%和14.0%,而冻融循环140次后CFRP片材的弹性模量却与未冻融时基本相当,冻融循环60次后CFRP片材的抗拉强度降低6.1%,但在接下来的冻融循环后基本保持稳定或略有增长;冻融循环后,AFRP片材和CFRP片材的断裂伸长率均与未冻融时基本相当或有所偏高,但AFRP片材的变化幅度相比CFRP片材略大;冻融循环140次后,环氧胶黏剂的拉伸剪切强度无退化.
The mechanical behaviors of aramid and carbon fiber-reinforced polymer (AFRP and CFRP) sheets as well as a corresponding epoxy adhesive after 60, 80, 100, 120 and 140 freeze-thaw cycles, were experimentally in- vestigated, and the freeze-thaw resistance of the AFRP sheet was compared with that of the CFRP sheet. Experi- mental results show that ( 1 ) in comparison with the CFRP sheet, the AFRP sheet after the freeze-thaw cycling has a greater change of tensile properties, and shows a worse freeze-thaw resistance; (2) after 140 freeze-thaw cycles, the tensile strength and elastic modulus of the AFRP sheet decrease respectively by 8.2% and 14. 0% , in com- parison with those of the control sheet exposed to ambient conditions; (3) however, the elastic modulus of the CFRP sheet after 140 freeze-thaw cycles is close to that of the control one, and the tensile strength of the CFRP sheet experiences a loss of 6. 1% after 60 freeze-thaw cycles and then keeps almost constant or slightly increases ; (4) the rupture elongations of the AFRP and CFRP sheets after freeze-thaw cycling are close to or slightly higher than those of the control ones, but the variaiton range of the elongation of the AFRP sheet is wider than that of the CFRP sheet; and (5) there is no decrease in the tensile lap-shear strength of the epoxy adhesive after 140 freeze- thaw cycles.