Thermo-mechanical analysis of propagating instabilities in metals - from experiments to reliable numerical prediction

• Applicant: Professor Dr.-Ing. Andreas Menzel
• Subject Area: Mechanics
• Term: since 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 527828607

Material instabilities significantly affect the respective metal’s properties such as ductility, strength and fatigue resistance. Typical examples of material instabilities in metals are phase-transition and localisation phenomena. The latter are in the focus of this proposal, namely propagating material instabilities in the form of Lueders bands and the Portevin-Le Chatelier (PLC) effect. The occurrence and evolution of such bands of plastic deformation, related to so-called strain aging, are known to depend on both strain rate and temperature. The understanding and reliable prediction of propagating Lueders and PLC bands are of key importance for resource-efficient design of components and structures made of materials showing these phenomena. This requires advanced thermo-mechanical models that capture the initiation and evolution of these bands at different loading rates and temperature levels on the one hand, and advanced experimental investigations in the context of parameter identification on the other. A unified model that captures the reliable and simultaneous prediction of Lueders bands and the PLC effect at different loading rates and temperature levels, and which is identified based on full field displacement and temperature data, is not available in the literature. The goal of this proposal is to fill this gap and to establish such model together with identification based on experiments including full field data.

• DFG Programme: Research Grants
• International Connection: Poland
• Partner Organisation: Narodowe Centrum Nauki (NCN)
• Cooperation Partner: Professor Dr.-Ing. Jerzy Pamin