基于应变的方法来预测增材制造的格子结构的疲劳失效
Antonio Coluccia1, Giorgio De Pasquale2
1Smart Structures and Systems Laboratory, Department of Mechanical and Aerospace Engineering, Politecnico di Torino, Corso Duca degli Abruzzi 24, 10129, Turin, Italy. antonio.coluccia@polito.it.
Scientific reports
|December 20, 2023
概括
本研究介绍了增材制造格子结构中疲劳失效的预测模型. 基于有限元方法的模型准确地预测了故障位置,这对于在苛刻的应用中提高元件耐用性至关重要.
科学领域:
- 材料科学 材料科学 材料科学
- 机械工程 机械工程
- 计算力学 计算力学 计算力学
背景情况:
- 格子结构在航空航天,汽车和生物医学领域至关重要.
- 耐疲劳性是格子材料结构应用的关键要求.
- 在增材制造的格子中准确预测疲劳失效是必不可少的.
研究的目的:
- 开发和验证一种预测模型,用于增材制造的格子结构的疲劳故障.
- 为了识别关键的晶格细胞和预测疲劳裂核化部位.
- 用已确定的故障标准评估部件疲劳极限.
主要方法:
- 利用有限元 (FE) 方法与线性同质化来降低计算成本.
- 采用基于菌株的参数来识别关键格子细胞.
- 应用了Crossland多轴疲劳失败标准来确定疲劳极限.
主要成果:
- 预测模型准确地预测了18个测试的Inconel 625标本中的17个故障位置.
- 失败始终发生在具有最大应变张力标准的区域.
- 该模型估计最大力为20N,以防止疲劳失效.
结论:
- 提出的基于FE的模型是分析格子结构疲劳的一个有价值的工具.
- 该方法有效预测疲劳裂核和组件故障.
- 了解应变分布是防止增材制造格子中疲劳失效的关键.
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