https://sam.ensam.eu:443 The DSpace digital repository system captures, stores, indexes, preserves, and distributes digital research material. Wed, 13 May 2026 13:38:40 GMT 2026-05-13T13:38:40Z http://hdl.handle.net/10985/27041 Udimet 720Li as a potential alternative for optimised aeroengine turbines: Thermophysical and thermomechanical characterisation under wide-ranging testing conditions ORTIZ-DE-ZARATE, Gorka; TIBA, Idriss; MADARIAGA, Aitor; LINAZA, Arantza; GARAY, Ainhara; GERMAIN, Guenael; ARRAZOLA, Pedro J. The need to reduce fuel consumption and emissions is driving advances in aeroengine performance. Efficiency gains are limited by the capacity of the turbine material to withstand the high thermomechanical loads of the combustion process. Nickel-based alloy Udimet 720Li has emerged as a promising alternative to the most widely used Inconel 718 for critical aeroengine components. Nonetheless, its material properties under industry-relevant conditions remain understudied, hindering industrial implementation. Furthermore, discrepancies in the methodology for applying adiabatic heating correction in thermomechanical tests on nickel-based alloys prevent comparability of studies and alloys. This paper presents the thermophysical and thermomechanical properties of forged and heat-treated Udimet 720Li to enable advanced aeroengine design and manufacture. A novel adiabatic heating correction procedure is also proposed for thermomechanical tests. Thermophysical properties (specific heat, density, diffusivity, thermal expansion, and conductivity) were characterised for temperatures 20–1200 °C. Thermomechanical properties were obtained for temperatures 20–1100 °C and strain rates 0.01–100 s-1 with cylinder compression tests. The results show that Udimet 720Li exhibits higher thermomechanical properties than Inconel 718 at elevated temperatures and can withstand greater in-service temperatures (8–23 %) due to the higher γ’ strengthening phase content which remains stable up to 760 °C. Fri, 07 Feb 2025 00:00:00 GMT http://hdl.handle.net/10985/27041 2025-02-07T00:00:00Z ORTIZ-DE-ZARATE, Gorka TIBA, Idriss MADARIAGA, Aitor LINAZA, Arantza GARAY, Ainhara GERMAIN, Guenael ARRAZOLA, Pedro J. The need to reduce fuel consumption and emissions is driving advances in aeroengine performance. Efficiency gains are limited by the capacity of the turbine material to withstand the high thermomechanical loads of the combustion process. Nickel-based alloy Udimet 720Li has emerged as a promising alternative to the most widely used Inconel 718 for critical aeroengine components. Nonetheless, its material properties under industry-relevant conditions remain understudied, hindering industrial implementation. Furthermore, discrepancies in the methodology for applying adiabatic heating correction in thermomechanical tests on nickel-based alloys prevent comparability of studies and alloys. This paper presents the thermophysical and thermomechanical properties of forged and heat-treated Udimet 720Li to enable advanced aeroengine design and manufacture. A novel adiabatic heating correction procedure is also proposed for thermomechanical tests. Thermophysical properties (specific heat, density, diffusivity, thermal expansion, and conductivity) were characterised for temperatures 20–1200 °C. Thermomechanical properties were obtained for temperatures 20–1100 °C and strain rates 0.01–100 s-1 with cylinder compression tests. The results show that Udimet 720Li exhibits higher thermomechanical properties than Inconel 718 at elevated temperatures and can withstand greater in-service temperatures (8–23 %) due to the higher γ’ strengthening phase content which remains stable up to 760 °C. http://hdl.handle.net/10985/27042 Development and optimization of a finite element model with remeshing and Lagrangian formulation for the simulation of high deformation manufacturing processes VALDIVIA-MALDONADO, Ignacio-Manuel; ORUNA, Ainara; ORTIZ-DE-ZARATE, Gorka; DUCOBU, François; GERMAIN, Guenael; ARRAZOLA, Pedro J. High deformation manufacturing processes, such as forming and machining, are complex physical phenomena involving severe thermomechanical and chemical loads. Traditional industrial-scale empirical methods involve high tooling and preparation costs and long lead times before manufacturing, which is undesirable in modern industry. The use of predictive models helps to reduce these weaknesses. Finite Element Method (FEM) models are a useful, reliable and cost-effective tool for studying manufacturing processes. Several approaches have been used to model these processes with the FEM. The Lagrangian formulation with implicit time integration scheme is the most widely used because of its reliability. However, element distortion due to severe plastic deformation and chip separation, in the case of machining, has always been a major concern of this approach. This paper therefore presents the development of a customizable and optimized FEM model with Lagrangian formulation and remeshing technique that solve the mesh distortion problem. The model was developed using the general-purpose software Abaqus/Standard commanded by Python scripting. The remeshing criterion is based on the relative plastic deformation at each load increment controlled by two subroutines working together UVARM+URDFIL. A forming problem was selected to optimize the mesh size and number of remeshings with the goal of reducing the simulation time. Then, the proposed model was compared to Lagrangian models without remeshing and Arbitrary Lagrangian-Eulerian (ALE) formulation. The model was also experimentally validated demonstrating improvements over other approaches and formulations, and laying the foundation for further development, such as applying it to the machining process. Tue, 28 Oct 2025 00:00:00 GMT http://hdl.handle.net/10985/27042 2025-10-28T00:00:00Z VALDIVIA-MALDONADO, Ignacio-Manuel ORUNA, Ainara ORTIZ-DE-ZARATE, Gorka DUCOBU, François GERMAIN, Guenael ARRAZOLA, Pedro J. High deformation manufacturing processes, such as forming and machining, are complex physical phenomena involving severe thermomechanical and chemical loads. Traditional industrial-scale empirical methods involve high tooling and preparation costs and long lead times before manufacturing, which is undesirable in modern industry. The use of predictive models helps to reduce these weaknesses. Finite Element Method (FEM) models are a useful, reliable and cost-effective tool for studying manufacturing processes. Several approaches have been used to model these processes with the FEM. The Lagrangian formulation with implicit time integration scheme is the most widely used because of its reliability. However, element distortion due to severe plastic deformation and chip separation, in the case of machining, has always been a major concern of this approach. This paper therefore presents the development of a customizable and optimized FEM model with Lagrangian formulation and remeshing technique that solve the mesh distortion problem. The model was developed using the general-purpose software Abaqus/Standard commanded by Python scripting. The remeshing criterion is based on the relative plastic deformation at each load increment controlled by two subroutines working together UVARM+URDFIL. A forming problem was selected to optimize the mesh size and number of remeshings with the goal of reducing the simulation time. Then, the proposed model was compared to Lagrangian models without remeshing and Arbitrary Lagrangian-Eulerian (ALE) formulation. The model was also experimentally validated demonstrating improvements over other approaches and formulations, and laying the foundation for further development, such as applying it to the machining process.