The metallic alloys for aeronautic application has been an important research area in our group for about twenty years. The development of high performance and reliable alloys requires understanding of the micro and nano structures at different scales as well as the elementary mechanisms responsible of the macroscopic mechanical properties. Our studies are mainly supported by TEM analysis of the deformation micromechanisms. We proceed classically by the post mortem observation of macroscopically deformed samples and we also carry out deformation tests inside the TEM : the “in situ deformation”.
Measurements of mechanical properties by deformation and creep tests and modeling by a finite elementary approach are tools we used too.
Among the current or recently investigated subjects, it can be listed superalloy ageing, mechanical properties of the Ti6Al4V (TA6V) alloy and effect of a surface treatment, structural hardening of aluminium alloys and martensitic steels, study of the lamellar structure formation and the high temperature behavior of intermetallic TiAl alloys. Concerning these TiAl alloys and some other materials, development of new alloys and fabrication of near net-shape components are processed by Spark Plasma Sintering.
More generally, these research activities have allowed an expertise on metallic alloys to be built up at CEMES.