SYNCHROTRON X-RAY CHARACTERIZATION OF ANISOTROPIC MICROSTRUCTURES OF METALS AND ALLOYS SUBJECT TO SEVERE PLASTIC DEFORMATION.

R. BOLMARO; E. BENNATTI; N. DE VINCENTIS; M. AVALOS; A. KLIAUGA; M. FERRANTE; A. SALCEDO GARRIDO; F. CRUZ GANDARILLA; N. SCHELL; H. BROKMEIER

Cancún

Congreso; XXIV International Materials Research Congress; 2015

IMRS

Several SeverePlastic Deformation (SPD) processes have been developed that allow theproduction of ultra-fine (micro-nano) structured metals and alloys. Simultaneous increase in strengthand ductility are among the main sought properties on SPD processed materials. Twins,dislocation arrays and grain size evolution are the main microstructurefeatures associated with macroscopic properties. Synchrotron radiation has relativelyrecently achieved wide availability and technical feasibility to be routinely usedfor the determination of direction dependent crystallographic data. Texture hasbeen long analyzed by this method but microstructure has been inspected only ona limited number of directions due to the difficulties for automatic analysis,despite the information is already available.Wepresent a few typical alloys subject to SPD processing exemplifying theanisotropic development of microstructure. The data was taken at DESY-Hamburg,Petra III GEM beam line by transmission geometry. Debye-Scherrer image plateswere batch processed using CMWP implementation of Warren-Averbach peakbroadening analysis. The final data is shown as Generalized Pole Figures forthe main parameters and variables (grain sizes, dislocation densities, twindensities, correlation factors, etc.). Results are correlated with slip systemactivities, stacking faults and texture. The anisotropic storage ofdislocations and preferential grain size diminution, as well as the rest offitting parameters, are attempted to be rationalized on micromechanical basis.