Micro-macro characterization and modeling of fatigue properties of hybrid welded joint of AlSi10Mg parts produced by selective laser melting and casting

选区激光熔化铸造 AlSi10Mg 零件混合焊接接头疲劳性能的微观-宏观表征和建模

• 批准号: 450156756
• 负责人: Professorin Dr.-Ing. Ghazal Moeini
• 金额: --
• 依托单位: Institut für Maschinenbau
• 依托单位国家: 德国
• 项目类别: Research Grants
• 资助国家: 德国
• 项目状态: 未结题
• 来源: https://gepris.dfg.de/gepris/projekt/450156756?language=en
• 关键词: Micro; macro; characterization; modeling; fatigue

Innovative lightweight design requires coordination of optimized component design, adapted manufacturing processes and appropriate material selection. Selective laser melting (SLM), as a metal additive manufacturing process, provides the advantage of virtually tool-free manufacturing almost without any limitations regarding structural complexity. However, a major restriction for the widespread application of SLM as an industrial manufacturing procedure is the limited size of the products. Therefore, there is a clear need to study the weldability of additively manufactured components to conventionally manufactured components in assemblies. Particularly, friction stir welding (FSW), as a solid-state welding process, is numerously employed in order to avoid common weld solidification related problems. However, there is still lack of quantitative description of the influence of inhomogeneous microstructure and porosity on the variability of fatigue response of friction stir welded hybrid joint of additive manufactured parts, which makes it difficult to specify the safety factor for cyclic loading conditions being important for many industrial applications. Additionally, the efficient development and optimization of SLM welded joints requires simulation, where the microstructural heterogeneity of local areas of the welded parts must be taken into account.The main goal of the proposed research project is to develop a microstructure- and defect-sensitive computational scheme to predict the fatigue behavior of friction stir welded joint partners produced by SLM and casting processes, taking into account the microstructural features of all regions in the welded joint, i.e. microstructure, chemical composition, phase fractions and imperfections (i.e. porosity). Lightweight aluminum alloy AlSi10Mg samples processed by SLM and casting processes will be considered. Solid-state friction stir welding will be used to produce sound welds of hybrid components.Comprehensive mechanical and microstructural characterization will be performed on the SLM and as-cast AlSi10Mg components as well as their friction stir welded joints. The material characterization provides the necessary input for the development of a microstructure- and defect-sensitive fatigue model of the hybrid welded joint. The microstructure- and defect-sensitive fatigue simulation will be performed based on the real microstructure of local areas of the welded joint. Eventually, the effect of microstructure characteristics on the local mechanical properties, especially the fatigue behavior, of the SLM component and the hybrid welded joint will be simulated and validated with the experiments.

创新的轻量化设计需要协调优化的部件设计、适应的制造工艺和适当的材料选择。选择性激光熔化（SLM）作为一种金属增材制造工艺，具有几乎无需工具制造的优势，几乎没有结构复杂性的任何限制。然而，SLM作为工业制造工艺广泛应用的一个主要限制是产品的尺寸有限。因此，显然需要研究增材制造组件与组件中传统制造组件的可焊性。特别地，搅拌摩擦焊（FSW）作为固态焊接工艺被广泛采用以避免常见的焊接凝固相关问题。然而，对于不均匀微观结构和孔隙率对增材制造零件搅拌摩擦焊混合接头疲劳响应变异性的影响仍然缺乏定量描述，这使得很难指定对于许多工业应用很重要的循环载荷条件的安全系数。此外，SLM 焊接接头的高效开发和优化需要进行仿真，其中必须考虑焊接零件局部区域的微观结构不均匀性。拟议研究项目的主要目标是开发一种微观结构和缺陷敏感的计算方案，以预测通过 SLM 和铸造工艺生产的搅拌摩擦焊接头的疲劳行为，同时考虑到所有区域的微观结构特征。 焊接接头，即微观结构、化学成分、相分数和缺陷（即孔隙率）。将考虑采用 SLM 和铸造工艺加工的轻质铝合金 AlSi10Mg 样品。固态搅拌摩擦焊将用于生产混合部件的良好焊缝。将对 SLM 和铸态 AlSi10Mg 部件及其搅拌摩擦焊接头进行全面的机械和微观结构表征。材料表征为开发混合焊接接头的微观结构和缺陷敏感疲劳模型提供了必要的输入。微观结构和缺陷敏感的疲劳模拟将基于焊接接头局部区域的真实微观结构进行。最终，微观组织特征对SLM部件和混合焊接接头局部力学性能，特别是疲劳行为的影响将通过实验进行模拟和验证。