X-Ray Diffraction and EBSD Characterization of IF Steel Processed by Accumulative Roll Bonding

FRANCISCO CRUZ GANDARILLA; ANA MARÍA SALCEDO GARRIDO; BOLMARO, RAÚL E.; N. S. DE VINCENTIS; MARTINA AVALOS; THIERRY BAUDIN; JORGE GERARDO CABAÑAS-MORENO; HECTOR J.DORANTES ROSALES

Cancún

Congreso; XXIV International Materials Research Congress; 2015

Sociedad Mexicana de Materiales

Accumulative Roll Bonding {ARB) is one of the so-called severe plastic deformation {SPD) processes that permit to obtain metals and alloys withultrafine {micro-nano) structure. Materials with ultrafine grains present attractive properties like the simultaneous increase in strength and ductility. The interest in these materials is related with two aspects. One is their mechanical properties, the other is related with the clarification of the microstructure evolution {texture, grain size, grain boundary types, microdeformation, crystallite size, dislocations, etc.) occurring during the processing.The objective of this work is to study the texture and the microstructure, texture, grain size, grain boundary character, Kernel Average Misorientation-KAM, grain reference orientation deviation, lattice parameters, microdeformation, crystallite size, dislocations density and spatial arrangement) in an interstitial free steel {IF) deformed by ARB using Electron Backscatter Diffraction {EBSD) and X-ray diffraction {XRD), for different processing cycles.Texture changes are observed with increasing number of ARB cycles. In the early cycles, the a and y fiber texturas are the principal components, forming subgrain agglomerations with band morphology and irregular through-thickness volume. With increasing number of cycles a tendency towards a random orientation is obtained. The KAM remains constant in the first cycles and decreases for the 5th cycle. In the initial state the grain size is between 20-40 IJm and after 3 cycles the grain size has a submicrometric dimension.Crystallite sizes and microdeformation do not change appreciably with the number of cycles. From these results we can conclude that in our case the principal factor that changes the mechanical properties is the decrease of grain size.