Progress of cross-scale mechanics in additive manufacturing technology for aeronautical application

Abstract

The application of metal additive manufacturing technology and products in the aviation field requires optimized structural design at macroscale and precise manufacture control at microscale. As one of the typical features of additive manufacture, microstructure inevitably affects the material performance. The research has shown that the uniformity, plasticity, and fatigue fracture characteristics of additive manufacturing materials are often inferior to traditional materials, while their strength, hardness, wear resistance, and some microscale properties are often better than traditional materials. The size effect in the micro/nano-scale and the heterogeneous characteristics of materials have a significant impact on metal materials with microstructures. Under different microstructures, materials can achieve a better balance between strength and ductility, which is also applicable to additively manufactured metals. Therefore, the process characteristics of additive manufacturing and the heterogeneities introduced by human design are both expected to significantly improve the comprehensive performance of metals, which have important guiding value for the application of metal additive manufacturing in the aviation field. However, since many of the mechanism of these phenomena are still unclear, the strength-ductility synergistic and antagonistic relationships with other properties of the materials are also worth further research.

Keywords

• cross-scale mechanics
• metal additive manufacturing
• strain gradient
• heterostructure