Synchrotron X-Ray Characterization of Anisotropic Microstructures of Metals and Alloys Subject to Severe Plastic Deformation

BOLMARO, RAÚL E.; EMANUEL BENATTI; NATALIA DE VINCENTIS; MARTINA AVALOS; ANDREA KLIAUGA; M FERRANTE; ANA MARÍA SALCEDO GARRIDO; FRANCISCO CRUZ GANDARILLA; NORBERT SCHELL; H.-G. BROKMEIER

Cancún

Congreso; XXIV International Materials Research Congress; 2015

Sociedad Mexicana de Materiales

Several Severe Plastic Deformation (SPD) processes have been developed that allow the production of ultra-fine (micro-nano) structured metals and alloys. Simultaneous increase in strength and ductility are among the main sought properties on SPD processed materials. Twins, dislocation arrays and grain size evolution are the main microstructure features associated with macroscopic properties. Synchrotron radiation has relatively recently achieved wide availability and technical feasibility to be routinely used for the determination of direction dependent crystallographic data. Texture has been long analyzed by this method but microstructure has been inspected only on a limited number of directions due to the difficulties for automatic analysis, despite the information is already available.We present a few typical alloys subject to SPD processing exemplifying the anisotropic development of microstructure. The data was taken at DESY-Hamburg, Petra III GEM beam line by transmission geometry. Debye-Scherrer image plates were batch processed using CMWP implementation of Warren-Averbach peak broadening analysis. The final data is shown as Generalized Pole Figures for the main parameters and variables (grain sizes, dislocation densities, twin densities, correlation factors, etc.). Results are correlated with slip system activities, stacking faults and texture. The anisotropic storage of dislocations and preferential grain size diminution, as well as the rest of fitting parameters, are attempted to be rationalized on micromechanical basis.