The effect of environmental conditions on the fracture behaviour of two types of adhesively bonded joints (wet-aged and non-aged) is experimentally studied under mode II loading. End Loaded Split tests were performed at various temperatures (−55 °C, room temperature (RT) and 80 °C) on non-aged and aged specimens. The non-aged specimens were stored in a laboratory under controlled conditions at RT (23 °C/55 RH) while the wet-aged specimens were exposed to accelerated ageing in an environmental chamber at 70 °C/85% RH for four years. The data reduction was applied using an inverse method and two other direct methods. A good agreement between these methods is observed. The analysis of the obtained results shows that extremely long aging times considerably affect the fracture response of bonded joints under mode II (the fracture toughness of the wet-aged specimens degraded by more than 30%). Furthermore, testing at high or cryogenic temperatures has a significant effect on the fracture response. Indeed, testing at high temperatures was observed to increase the fracture toughness (this increase ranged from 8% to 80%) while cryogenic temperatures increased the brittleness of the adhesive which caused a substantial reduction (more than 25%) in the fracture toughness of the bonded joint.

在模式II载荷下，通过实验研究了环境条件对两种类型的粘结接头（湿老化和非老化）的断裂行为的影响。在不同的温度（-55°C，室温（RT）和80°C）下对未老化和老化的试样进行了端部载荷分裂测试。将未老化的标本在受控条件下于室温（23°C / 55 RH）下保存在实验室中，而将湿老化的标本在70°C / 85％RH的环境室内暴露于加速老化下四年。使用逆方法和其他两种直接方法进行数据缩减。这些方法之间观察到很好的一致性。对所得结果的分析表明，极长的时效时间会显着影响II模式下粘结接头的断裂响应（湿时效试样的断裂韧性降低了30％以上）。此外，在高温或低温下进行测试对断裂响应有重大影响。确实，观察到在高温下的测试增加了断裂韧性（这种增加范围为8％至80％），而低温则增加了胶粘剂的脆性，从而导致胶粘剂的断裂韧性大大降低（超过25％）。键合接头。