Vanadium Carbide Dissolution during Austenitisation of a Model Microalloyed FeCV Steel
High performance commercial micro alloyed steels contain elements such as vanadium, which leads to a fine dispersion of vanadium carbide precipitates. The precipitation state, in terms of volume fraction and size distribution, plays a significant role in final mechanical properties of the material. Different austenitisation heat treatments were performed on a model ternary alloy FeCV. Precipitation states were characterised combining different experimental techniques. TEM was used to identify the chemical composition of observed precipitates. ICP mass spectroscopy was performed to measure the volume fraction of precipitates. The size distribution was studied by SEM. Results are characterist…
Temperature rise during laser-induced self-organization of nanoparticle gratings revealed by Raman microspectroscopy and electron microscopy
International audience
Formation of Bimetallic Nanoparticle Arrays and Evidence for their Stability at High Temperature under Gas Pressure in the Environmental TEM - VIRTUAL
MICROSCOPIE+MEME+EEH:FCA:LBU:TEP; International audience; Supported catalysts are generally composed of, at least, one nanometric active phase deposited and/or synthesized at the surface of a convenient nanometer/micrometer powder support. As such these are rather complex systems with many variable parameters: dispersion on the support, size distribution, morphology, structure, defects, variable chemical phases, variable exposed facets of the active phases, interaction with the support, etc. It is thus quite cumbersome to correlate a catalytic behavior with specific physicochemical properties. The synthesis of nanometric particles (NPs) with well controlled characteristics is thus crucial t…