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The influence of high-pressure torsion (HPT) and annealing on microstructure, texture and thermal stability of an immiscible composite Cu43%Cr alloy was studied using electron backscatter diffraction, X-ray diffraction and microhardness measurements. As-received alloy samples were subjected to HPT and subsequent annealing treatment in the range of 210-850°C for 1 h in order to develop ultrafine-grained (UFG) microstructures and highlight their thermal stability. The Cu and Cr grains were refined to ~0.45 and ~0.39 µm, respectively and exhibited equiaxed morphology. The crystallographic texture was of shear type in both Cu and Cr with the domination of C and F orientations, respectively. The UFG microstructure and texture were retained in the Cu43%Cr alloy up to 850°C. The global results show that the immiscible composite Cu43%Cr alloy exhibits a high thermal stability up to 850°C. The evolution of the microstructure, texture and thermal stability of the UFG Cu43%Cr alloy was compared to published data and available models. [ABSTRACT FROM AUTHOR]

The effect of annealing on the microstructure and the texture development was investigated in a particle containing AA3104 aluminium alloy. The samples were processed at room temperature by high-pressure torsion (HPT) up to ten turns. The nucleation of new grains was analyzed by a transmission electron microscope equipped with a system for local orientation measurements and a heating holder.

Abstract: This study investigates the effect of impurities, especially sulfur, on the recrystallization texture and microstructure of drawn copper-ETP wires (38% area reduction). Using neutron diffraction, we find that in all Cu samples the recrystallization texture is primarily composed of the 〈001〉//ND and 〈111〉//ND fiber components, regardless of impurity content. In addition, the recrystallization kinetics is slower, especially the incubation time is longer, when the S impurity content increases. In order to explain this phenomenon, the formation process of recrystallization texture – i.e. nucleation/growth sequences of the new grains – has been investigated in detail by means of TEM and EBSD. It is observed that grains with the 〈001〉//ND orientation nucleate first, by coalescence of dislocation cells close to highly disoriented grain boundaries, which suggests that sulfur impurities delay the process of recovery, necessary for nuclei formation, as well as the mobility of the grain boundaries during recrystallization. [Copyright &y& Elsevier]

After wire-drawing, the orientation dependent stored elastic energy was measured by neutron diffraction in electrolytic tough pitch copper (ETP 99.99% Cu) wires to improve the knowledge on the chemical composition effect on the static recrystallization behavior. The line broadening measurements on relatively low deformed samples have shown that the stored energy related to the main fibers--the texture develops major {111}(uvw) and minor {001}

After wire-drawing, the orientation dependent stored elastic energy was measured by neutron diffraction in electrolytic tough pitch copper (ETP 99.99% Cu) wires to improve the knowledge on the chemical composition effect on the static recrystallization behavior. The line broadening measurements on relatively low deformed samples have shown that the stored energy related to the main fibers—the texture develops major [111]〈uvw〉 and minor [001]〈uvw〉 fibers—is about 2-4 J/mol and that the stored energy ratio [111]〈uvw〉 decreases when the total impurity content increases. Some hypotheses about the relationship between recrystallization process. recovery and stored energy are finally proposed, and some assumptions about the recrystallization mechanisms are set. [ABSTRACT FROM AUTHOR]

An improved Monte Carlo approach for simulation of recrystallization from experimental data is presented. The orientation and stored energy maps derived by orientation imaging microscopy and the X-ray bulk texture of a Fe–50%Ni alloy are used as input data. A realistic description of the dependence of grain boundary properties on misorientation is used to simulate the nucleation and growth of the new recrystallized grains. [Copyright &y& Elsevier]

The spatial distribution of plastic deformation and grain orientation surrounding hydrogen-induced cracks (HIC) is investigated in samples of API-5L-X46 pipeline steel using scanning electron microscopy and electron backscattering diffraction (EBSD). This work shows direct experimental evidence of the influence of microstructure, microtexture and mesotexture on HIC crack path. [Copyright &y& Elsevier]