Nanostructures and unique properties in intermetallics, subjected to severe plastic deformation

The strength and ductility of several nanostructured intermetallics produced by severe plastic deformation (SPD) were studied. Transmission electron microscopy (TEM) studies of foils were conducting using a JEM-200 SX and a JEOL ARM 1000 electron microscopes. X ray diffraction was used for structural analysis and for estimating the long range stresses. Mechanical tensile behavior was examined with a computer controlled device for tests of small samples at various strain rates. Results demonstrate that severed plastic deformation by high pressure torsion can strongly refine microstructure in the intermetallic compounds until a nanometer range and lead to metastable states due to disordering and/or amorphization.