Experimentelle und modellmäßige Bewertung der dreidimensionalen Auswirkung mikrostruktureller Barrieren während der Rissinitiierungphase VHCF-beanspruchter Werkstoffe

VHCF 应力材料裂纹萌生阶段微观结构障碍三维影响的实验和建模评估

• 批准号: 172277823
• 负责人: Professor Dr.-Ing. Hans Jürgen Christ
• 金额: --
• 依托单位: Lehrstuhl für Materialkunde und Werkstoffprüfung
• 依托单位国家: 德国
• 项目类别: Priority Programmes
• 财政年份: 2010
• 资助国家: 德国
• 起止时间: 2009-12-31 至 2017-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/172277823?language=en
• 关键词: Experimentelle; und; modellm; ige; Bewertung

Even after one billion cycles, components made of metallic materials may show traces of plastic deformation without being failed. However, the same components can fracture at the same load but a lower number of cycles. The hypothesis of the present research that the resistance of microstructural barriers to dislocation motion decides about the occurrence of fatigue damage will be quantified by duplex steel of different strength of the ferrite and austenite phase. Furthermore, important aspects, such as the simultaneous plasticity and residual stress distribution between the two phases, as well as the stochastic arrangement of fatigue-critical microstructural clusters will be analyzed. The important question about the influence of environmental effects on the VHCFdamage is going to be addressed by experiments in different atmospheres. Three interacting modern experimental and theoretical approaches are used: (i) ultrasonic fatigue testing in combination with in-situ analysis techniques (ii) three-dimensional microstructural reconstruction and spatially-resolved diffraction measurements using high energy synchrotron radiation and (iii) finite element modeling of the elastic and plastic anisotropic fatigue deformation within the twophase microstructure as a base of a damage-tolerant life prediction concept for the VHCF regime as well as an possibility for structural optimization of fatigue-resistant materials.

即使经过十亿次循环，由金属材料制成的部件也可能会出现塑性变形的痕迹，而不会出现故障。然而，相同的部件可能在相同的载荷但较少的循环次数下断裂。目前研究的假设是，微观结构障碍对位错运动的抵抗力决定了疲劳损伤的发生，这将通过不同强度的铁素体和奥氏体相的双相钢来量化。此外，还将分析重要方面，例如两相之间的同时塑性和残余应力分布，以及疲劳关键微观结构簇的随机排列。关于环境影响对 VHCF 损害影响的重要问题将通过不同大气中的实验来解决。使用三种相互作用的现代实验和理论方法：（i）超声波疲劳测试与原位分析技术相结合（ii）使用高能同步加速器辐射的三维微观结构重建和空间分辨衍射测量以及（iii）有限元建模两相微观结构内弹性和塑性各向异性疲劳变形的研究，作为 VHCF 体系耐损伤寿命预测概念的基础，以及抗疲劳材料结构优化的可能性。