A smooth particle hydrodynamic (SPH) simulation of an additive friction stir deposition (AFSD) repair was used to inform a multi-physics approach to predict the fatigue life of a high strength aluminum alloy. The AFSD process is a solid-state layer-by-layer additive manufacturing approach in which a hollow tool containing feedstock is used to deposit material. While an understanding of the evolving microstructures is necessary to predict material performance, the elevated temperatures and strain rates associated with severe plastic deformation processes (SPDP) make accurate collection of experimental data within AFSD difficult. Without the ability to experimentally determine material history within the AFSD process, an SPH model was employed to predict the thermomechanical history. The SPH simulation of an AFSD repair was used to inform several microstructural models to predict material history during and after processing with AFSD and a post-processing heat treatment. These microstructure models are then used to inform a mechanistic microstructure and performance model to predict the fatigue life of an AFSD repair in AA7075.

使用附加搅拌摩擦沉积 (AFSD) 修复的平滑粒子流体动力学 (SPH) 模拟为多物理场方法提供信息，以预测高强度铝合金的疲劳寿命。AFSD 工艺是一种固态逐层增材制造方法，其中使用含有原料的空心工具来沉积材料。虽然了解不断变化的微观结构对于预测材料性能是必要的，但与严重塑性变形过程 (SPDP) 相关的高温和应变率使得在 AFSD 内准确收集实验数据变得困难。由于无法通过实验确定 AFSD 过程中的材料历史，因此采用 SPH 模型来预测热机械历史。AFSD 修复的 SPH 模拟用于为多个微观结构模型提供信息，以预测使用 AFSD 和后处理热处理期间和之后的材料历史。然后使用这些微观结构模型为机械微观结构和性能模型提供信息，以预测 AA7075 中 AFSD 修复的疲劳寿命。