航空金属材料的损伤机制与预测方法

损伤是航空结构件加工制造与服役中的共性问题。以微观损伤机制与损伤预测模型为主要关注点，论述了典型航空用铝合金、钛合金中损伤形核、扩展的影响因素以及宏观、细观尺度损伤断裂的预测方法。对于塑性成形过程，以受力状态为切入点，阐述了不同应力状态下损伤演化的差异性，介绍了基于应力状态损伤模型在航空材料中的应用。对于疲劳损伤问题，总结了不同体系合金中的微观影响因素，如第二相颗粒、晶体取向等，讨论了疲劳预测方法在航空用铝合金、钛合金中的应用。将局部应力应变集中归纳为损伤萌生、扩展的外因，而材料内部缺陷、界面等为内因，塑性变形、疲劳过程的损伤累积均为内、外因综合作用的结果。通过归纳损伤机制研究进展与问题，分析宏、细观预测方法的优缺点，提出以共性规律与通用性预测方法为重点的发展方向。

Damage mechanism and fracture model of aeronautical metals

Damage is a common issue in the processing, manufacturing and service of aviation structural parts.Focusing on the damage mechanism and modeling of typical aviation aluminum and titanium alloys, the influencing factors of damage and the prediction methods of macro-scale and micro-scale were discussed. Stress state was a key factor in affecting the damage behavior in plastic forming process. This paper expounds the differences of damage evolution under different stress states, and introduces the application of stress-based damage model in aviation materials. For the fatigue damage, the micro influencing factors in different alloys, such as second phase particles, crystal orientation and so on, were summarized, and the application of the fatigue prediction methodologies in typical aviation aluminum and titanium alloys were discussed. Taking the local strain and stress concentration as external cause and the defect in microstructure as internal cause, The damage accumulation is considered as the result of the combination of the above two factors. By summarizing the progress and problems of damage mechanism, and discussing the advantages and disadvantages of macro and meso prediction methods, this paper puts forward the development direction of common law and universal prediction methods.