A5090192729- High Temperature Alloys and Creep
- Microstructure and mechanical properties
- Microstructure and Mechanical Properties of Steels
- Intermetallics and Advanced Alloy Properties
- Advanced Materials Characterization Techniques
- Titanium Alloys Microstructure and Properties
- Nuclear Materials and Properties
- Metallurgy and Material Forming
- Aluminum Alloy Microstructure Properties
- Metal and Thin Film Mechanics
- Force Microscopy Techniques and Applications
- Fatigue and fracture mechanics
- Additive Manufacturing Materials and Processes
- Metal Forming Simulation Techniques
- High-Temperature Coating Behaviors
- Thermodynamic and Structural Properties of Metals and Alloys
- High Entropy Alloys Studies
- Metallurgical and Alloy Processes
- Metal Alloys Wear and Properties
- Hydrogen embrittlement and corrosion behaviors in metals
- Semiconductor materials and interfaces
- Material Dynamics and Properties
- Material Properties and Applications
- Surface and Thin Film Phenomena
- Advanced Welding Techniques Analysis
Centre d’Élaboration de Matériaux et d’Études Structurales
2012-2024
Centre National de la Recherche Scientifique
2005-2021
Université de Toulouse
2012-2021
Institut Pprime
2014
École Nationale Supérieure de Mécanique et d'Aérotechnique
2014
Université de Poitiers
2014
Université Toulouse III - Paul Sabatier
2012-2013
The weak-beam technique of transmission electron microscopy has been used to analyse a new shearing configuration γ′ precipitates after creep at 700°C Ni-based superalloy for gas turbine discs. configurations are made up superlattice extrinsic stacking faults, matrix faults and individual (a/6)⟨112⟩ Shockley dislocations. This mechanism is initiated by the decorrelated movement two partials single (a/2)⟨110⟩ dislocation. propagation leading partial creates this process. phenomenon that...
The creep behaviour of the PM NR3 nickel-based superalloy has been studied at 700°C in a wide stress range as function its microstructure.It was first confirmed that this critical temperature coarse-grained microstructure preferable to fine-grained one obtain highest resistance.The role tertiary γ ′ phase precipitates coarsegrained investigated two levels typical both low and high regimes.Careful identification dislocation mechanisms by transmission electron microscopy performed strained...
AD730IM was designed to be a cost effective superalloy for high temperature turbine disks. This superalloy, strengthened by gamma prime precipitates, presents good ability cast and wrought process route combination between mechanical properties cost. A study performed optimize the aging sequence considering tensile, creep dwell-fatigue crack growth rate properties. Isothermal in 730-790°C range with various durations 4-16h were after 1080°C/4h solution heat treatment followed air cooling on...
This chapter contains sections titled: Introduction Material and Experimental Procedures Results Discussion Conclusions Acknowledgements
Abstract The chemical force acting on dislocations in a short-range-ordered concentrated Ni-based alloy is investigated by post mortem and in-situ transmission electron microscopy. For this purpose, the positions of pile-up are calculated, taking into account stress relaxation at free surfaces. calculation shows that distribution first only slightly affected presence surfaces, while length strongly depends thickness foil. Analysis pile-ups two alloys resulting from short-range order (SRO)...
Abstract The mobile dislocation pile-ups observed during in situ straining experiments have been used as probes to describe the short-range order (SRO) present phase of nickel-base superalloys. An experimental approach, based on measurement positions, characterise SRO has developed. This paper focuses main results we obtained this topic. A quantitative analysis allows get chemical forces associated with SRO, and also degree. For first time, energies are evaluated along a pile-up function...
Abstract Dislocation motion in short-range-ordered solid solutions under stress are investigated situ by transmission electron microscopy. For the first time, local reordering created back slip of mobile dislocations is proven to exist. movement within pile-ups produces disordering forward during loading, and unloading. Within a pile-up, driving force for this mechanism diffuse antiphase-boundary energy leading dislocation.
AD730tm was designed to be a cost effective superalloy for high temperature turbine disks.This superalloy, strengthened by gamma prime precipitates, presents good ability cast and wrought process route combination between mechanical properties cost.A study performed optimize the aging sequence considering tensile, creep dwell-fatigue crack growth rate properties.Isothermal in 730-790°C range with various durations 4-16h were after 1080°C/4h solution heat treatment followed air cooling on...
Abstract Polycrystalline samples of Al3Ti with the D022-type structure have been plastically deformed at 400°C. Observations using weak-beam transmission electron microscopy show activation dislocations <100] or <110] Burgers vectors. The fine [100] and [010] reveals strong stabilization effect on pure edge character. [110] superdislocations, resulting from interactions between perfect dislocations, are dissociated in two identical superpartials separated by an antiphase boundary (APB)....
The fine structure of slip lines in the γ-phase Ni-based superalloy single crystals has been investigated by situ atomic force microscopy observations specimen surface during deformation. For first time, dislocation is discussed terms short range order heterogeneity. A stress-driven unlocking mechanism observed pile-ups scanning bulk material. This strongly enhanced propagation other a few hundreds nanometers apart. modelling based on elasticity proposed and discussed.