Papers by Mirosław Wróbel
International Journal of Refractory Metals & Hard Materials, Feb 1, 2022
Polycrystalline Cu-5 wt %Al alloy was rolled initially to 30% deformation and 60% deformation and... more Polycrystalline Cu-5 wt %Al alloy was rolled initially to 30% deformation and 60% deformation and then additionally rolled after switching the rolling direction with the transverse direction to deformations: 10-80%. Examinations of the textures and microstructures after deformation and subsequent recrystallization were performed. It was found that the change in the direction of plastic flow alone is not sufficient for localization of the plastic deformation in the form of shear bands; also, the application of a large amount of deformation is required. The shear bands constitute the basic feature of microstructure in samples subjected to cross-rolling with the total true deformation greater then 0.9. Shear bands are the places where recrystallization commences and proceeds relatively fast. Regions between shear bands recrystallized at higher temperatures, however, the recrystallization proceeds slower and progress by the growth of grains from the former shear bands. The grain size after recrystallization is not uniform. Finer grains appear within former shear bands. The deformations imposed after change in the rolling direction slowly changes the alloy-type texture formed during the initial rolling. After the 80% reduction in thickness by the secondary rolling the texture being formed during the initial rolling is rotated around the normal direction by 90°. The recrystallization texture for that material (with a high density of shear bands) contain components which can be derived from the components of the deformation texture by their rotation around the common poles by angles about 40-50°.
Materials Science Forum, Aug 1, 2017
The TOF neutron diffraction measurements were done for Al/SiCp metal–matrix composite (17% of SiC... more The TOF neutron diffraction measurements were done for Al/SiCp metal–matrix composite (17% of SiC) subjected to T6 thermal treatment. Using three separated diffraction peaks of SiC phase and four peaks of Al phase, the lattice strains were measured for both phases independently during in situ tensile test. The experimental results were presented in comparison with elastoplastic model, which allows to find the values of parameters determining plastic deformation of Al matrix (critical resolved shear stress and hardening parameter). Additionally, the results of TOF method were compared with those which were obtained with monochromatic neutron radiation (LLB, Saclay). In the latter experiment Al/SiCp composite containing 25% of SiC was measured. It was shown that after elastoplastic deformation the mismatch stresses determined for both phases relax during tensile deformation.
The formation of texture and microstructure in polycrystalline Cu and Cu-5 wt. % Al alloy during ... more The formation of texture and microstructure in polycrystalline Cu and Cu-5 wt. % Al alloy during two modes of homogenous rolling have been compared. Two samples of each metal were rolled. One sample was rolled unidirectionally, while the other by reverse rolling. Some differences in the textures depending on the rolling mode have been observed in the range of deformation of the Cu-5 wt. % Al alloy where intensive twinning took place. It was also found that the texture of reverse rolling was more homogeneous across the thickness of the rolled alloy sheet than the texture of unidirectionally rolled material. No clear effect of the rolling mode on microstructure has been observed.
Journal of Microscopy, Mar 1, 2010
SummaryAn alloy with a chemical composition of Ti‐45Al‐5V (at.%) was synthesized by mechanical al... more SummaryAn alloy with a chemical composition of Ti‐45Al‐5V (at.%) was synthesized by mechanical alloying in a Szegvari‐type attritor from elemental powders of high purity. Before compaction, the powders were characterized by X‐ray diffraction and scanning as well as transmission electron microscopy. The compaction of powders was carried out by hot isostatic pressing and hot isostatic extrusion. The resulting material was subjected to microstructural and mechanical characterization. The microstructure investigated by transmission and scanning electron microscopy supplemented by X‐ray diffraction revealed that the bulk material was composed of a mixture of TiAl‐ and Ti3Al‐based phases, however, the typical lamellar microstructure for such alloys was not observed. The materials exhibited exceptionally high yield strength together with satisfactory ductility and fracture toughness. The high strength was unequivocally due to grain refinement and the presence of oxide dispersoid.
Textures and Microstructures, 1988
Materials Science Forum, Aug 1, 2002
ABSTRACT
Materials Characterization, Dec 1, 2001
Journal of Materials Processing Technology, Aug 1, 1995
ABSTRACT
Journal of Microscopy, Oct 1, 2006
Scripta Materialia, Jul 1, 2000
Inżynieria Materiałowa, 1998
Inżynieria Materiałowa, 1998
Scripta Materialia, Oct 1, 1997
Revue de métallurgie, Sep 1, 1997
ABSTRACT
Materials Science and Technology, Jun 1, 2000
The use of a single, accurate, and relatively quick experimental method suitable for determinatio... more The use of a single, accurate, and relatively quick experimental method suitable for determination of crystallographic texture and amounts of phases in the final product is of interest to some manufacturers. The suitability of an X-ray method for this purpose is evaluated in the present paper. The Schulz back reflection technique has been used to record incomplete pole figures of ferrite and austenite in a sample of commercial duplex stainless steel tube. The orientation distribution function was calculated for each phase and then used for the reproduction of complete pole figures. The complete pole figures were applied in quantitative phase analysis (QPhA), by a new method, free from texture induced errors. For comparison, the volume fraction of austenite and ferrite was also determined by means of the classic direct comparison method of Averbach and Cohen as well as by standard quantitative metallography. The proposed method of QPhA was applied for the examination of the amount of retained austenite in certain bearing construction elements. MST/3993
Journal of Materials Processing Technology, Aug 1, 1995
ABSTRACT
Acta Physica Polonica, 2018
Materials Chemistry and Physics, Aug 1, 2003
Microstructure and texture development during recrystallization of a Cu−Al single crystal with (1... more Microstructure and texture development during recrystallization of a Cu−Al single crystal with (100)[011] orientation deformed by cold rolling to 80% reduction in thickness were investigated. The strongest components of recrystallization texture show the following relationships with the main component of the deformation texture: 30° 〈111〉 and about 45° 〈111〉. The orientations of the first nucleated grains do not show such
Uploads
Papers by Mirosław Wróbel