Effects of CO2 enrichment and of the form of nitrogen supply on fruit and vegetable production

International audienc

Influence de la lumiere artificielle sur la croissance du plant de melon

National audienc

Quelques resultats sur la biologie de plantes a edulcorants

National audienc

Effects of CO2 enrichment and of the form of nitrogen supply on fruit and vegetable production

International audienc

Forcage des plantes en serre. Mode d'application du dioxyde de carbone

National audienc

La fertilisation carbonee gazeuse, moyen de forcage des productions horticoles en serre

National audienc

Action de l'eclairage artificiel sur la production en serre du plant de melon greffe

National audienc

Mineral nutrition and morphine production in Papaver somniferum

International audienc

Evolution of the nanoporous microstructure of sintered Ag at high temperature using in-situ X-ray nanotomography

International audienceSilver pastes sintering is a potential candidate for die bonding in power electronic modules. The joints, obtained by sintering, exhibit a significant pore fraction, thus reducing the density of the material compared to bulk silver. The mechanical properties (Young's modulus, yield strength and ultimate tensile stress) are then drastically altered. However, while careful analysis of the nanoporous structure has been reported in 2D, little is known about its quantitative spatial evolution during thermal aging and more specifically during temperature jumps endured by the assembly during operation. Here, high temperature evolutions of the 3D nanoporous structure have been observed in-situ using a heater fitted into the beamline 6-2c at SLAC-SSRL. Segmentation of the porosity and subsequent statistical analysis of the tomographic dataset reveal a complex evolution of the porous nanostructure including growth, separation and coalescence at a constant density. Such an analysis provides insight into the microstructural evolution of sintered nanoporous Ag joints in-service

Evolution of the nanoporous microstructure of sintered Ag at high temperature using in-situ X-ray nanotomography

International audienceSilver pastes sintering is a potential candidate for die bonding in power electronic modules. The joints, obtained by sintering, exhibit a significant pore fraction, thus reducing the density of the material compared to bulk silver. The mechanical properties (Young's modulus, yield strength and ultimate tensile stress) are then drastically altered. However, while careful analysis of the nanoporous structure has been reported in 2D, little is known about its quantitative spatial evolution during thermal aging and more specifically during temperature jumps endured by the assembly during operation. Here, high temperature evolutions of the 3D nanoporous structure have been observed in-situ using a heater fitted into the beamline 6-2c at SLAC-SSRL. Segmentation of the porosity and subsequent statistical analysis of the tomographic dataset reveal a complex evolution of the porous nanostructure including growth, separation and coalescence at a constant density. Such an analysis provides insight into the microstructural evolution of sintered nanoporous Ag joints in-service