Abstract: The grain-scale microstructure information of crystalline material is failed to be comprehensively considered in existing grain-scale mechanical behaviour simulation models of crystalline material miniature parts, and the incidence relation between part geometry and microstructure is neglected, which make the models low accuracy and difficult to be popularized. According to the microminiaturization tendency in the aerospace field, grain-scale pseudorandom modelling and simulations of Inconel-718, a conventionally used polycrystalline material for critical parts in high temperature applications, are carried out. The actual 3D microstructure statistical information of Inconel-718 is obtained, and the geometry-considered 3D pseudorandom grain-scale modelling method is introduced. Micro-pillar compression, micro bending and micro-gear rotation simulations are executed as the cases of micro-testing, micro-manufacturing and miniature-part serving. The necessity of considering geometrical features of crystalline material miniature parts during grain-scale simulations is emphasized, and the application prospect of the developed method is demonstrated. The developed grain-scale pseudorandom modelling method for polycrystalline material miniature parts is able to directly achieve grain-scale modelling and mechanical behavior simulation of arbitrary-shaped Inconel-718 miniature parts with high efficiency and accuracy, and it is also convenient to be extended to the application of other crystalline materials.

Key words: Inconel-718, miniature parts, pseudorandom, crystal plasticity finite element analysis