Acoustic Emission (AE) is used to monitor the fatigue behaviour of specimens made of aluminium alloy 7075-T6 and covered with different coating combinations: anodic oxidation (alumina) - primer layer (organic coating) - topcoat layer (organic coating)). AE monitoring allows to understand and differentiate the processes and damage mechanisms in action during fatigue for all types of specimens. The type of coating applied has a significant influence on the damage process and the fatigue lifetime of the material. AE-based indicators are defined to assess the overall damage state of the specimens during fatigue testing. Some indicators are based on the distinction of the acoustic activity acquired during the loading and unloading phases of the cycles. As an example, the joint analysis of these indicators on anodized samples allows to highlight characteristic times ranging from 15% to 70% of the specimen’s lifetime. The early time at 15% is related to the saturation of cracking of the oxide layer during the first cycles of fatigue tests. By 70% of failure life, the AE activity correlates with the propagation of the main crack in the substrate, assisted by brittle fracture of the surrounding oxide layer. These specific times provide information on the Remaining Useful Lifetime (RUL) of the material and could be used to anticipate future failure.

声发射 (AE) 用于监测由铝合金 7075-T6 制成并覆盖有不同涂层组合的试样的疲劳行为：阳极氧化（氧化铝）- 底漆层（有机涂层）- 面漆层（有机涂层））。AE 监测允许了解和区分所有类型样本在疲劳过程中起作用的过程和损伤机制。涂层的类型对材料的损伤过程和疲劳寿命有重大影响。定义了基于 AE 的指标，以评估疲劳测试过程中试样的整体损坏状态。一些指标是基于在周期的加载和卸载阶段获得的声学活动的区别。举个例子，对阳极氧化样品的这些指标进行联合分析可以突出显示样品寿命的 15% 到 70% 的特征时间。15% 的早期时间与疲劳测试的第一个循环期间氧化层开裂的饱和度有关。在 70% 的失效寿命中，AE 活动与基板中主裂纹的扩展相关，并辅以周围氧化层的脆性断裂。这些特定时间提供了有关材料剩余使用寿命 (RUL) 的信息，可用于预测未来的故障。AE 活动与基板中主裂纹的扩展相关，并辅以周围氧化层的脆性断裂。这些特定时间提供了有关材料剩余使用寿命 (RUL) 的信息，可用于预测未来的故障。AE 活动与基板中主裂纹的扩展相关，并辅以周围氧化层的脆性断裂。这些特定时间提供了有关材料剩余使用寿命 (RUL) 的信息，可用于预测未来的故障。