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In the most recent years the asymmetric rolling (AR) attracts attention of researchers and technologists. This process can improve some technological parameters (e.g. modification of rolling torque and load, power requirements, etc.) as well as provide the possibility of grain refinement in a relatively inexpensive way. Most of the reports concerning microstructural changes produced by AR refer to high deformations imposed in highly asymmetric conditions. However, such rolling conditions are difficult to control, so there are no prospects to their quick industrial implementation. The present paper refers to relatively low deformation and low asymmetry rate, that is much more interesting for the industry. It was shown that bending of the rolled band (important disadvantage of the AR technology) can be controlled by adjusting of the amount of deformation and asymmetry. It was also shown that ca. 30% reduction in thickness during cold rolling, together with a relatively low asymmetry, reduces significantly the grain size and produces a more fragmented microstructure inside grains of the polycrystalline copper comparing to the symmetric rolling (SR). The material hardness after AR is higher than after the SR. Moreover, the crystallographic texture asymmetry, expressed by its rotation around the transverse direction, is observed in the AR material.

The posterior part of the tympanic cavity comprises a depression called the sinus tympani (ST). The said structure is of outmost importance, e.g., in surgical procedures involving the middle ear, as apathology (microbial biofilm or cholesteatoma) present in this difficult to access location might hinder its effective treatment. The aim of the study was to evaluate anatomical variants of the sinus tympani in human adult petrous bones. For this purpose, 3D models of the ST were recreated from micro-CT scans of 44 dry petrous bone samples (19 female, 25 male), applying 3D Slicer, Meshmixer and MeshLab softwares. Anatomical variants of the ST were classified in terms of both shape and surface configuration. The internal configuration of the ST was classified as heterogeneous - containing small bony trabeculae and crests up to 1.0 mm in size, contrasting to homogeneous ST that characterizes a relatively smooth interior, or mere presence of minor depressions and mild folds. Female STs were more bowl-shaped (57.9%) than saccular (42.1%), and had heterogeneous surface configuration (52.6%) compared to homogeneous (47.4%). On the contrary, male STs were more saccular (52.0%) rather than bowl-shaped (48.0%), and predominantly had a heterogeneous surface (84.0%) over homogeneous (16.0%). A complex combination of ST features comprised of a saccular shape and heterogeneous surface occurred in 52.0% of males and in 15.8% of females (a statistically significant difference; p=0.0254, Fisher's exact test) seems to be clinically important because of its potential negative implication on health outcomes after surgery in case of e.g., cholesteatoma, and it may also favor chronic pathological processes. [ABSTRACT FROM AUTHOR]

The grain scale of materials is an area still open for investigations within the field of materials science. The most helpful tools to perform this type of research are diffraction methods. Within the research project presented in this paper two experiments were carried out employing two different types of radiation: neutron (ISIS) and synchrotron (ESRF). The aim of the work was to describe the stress state in the necking zone during the occurrence of a damage phenomenon (Fig. 1.) in separate phase and to check the level of the homogeneity. The supplemental tools were the finite elements method and self-consistent modeling – it testified, confirmed and completed our experimental results and allowed us to formulate the justifiable conclusions.

W pracy przedstawiono wyniki trójwymiarowej symulacji walcowania asymetrycznego, używając Metody Elementów Skończonych. Rozważono walcowanie stali niskowęglowej. Asymetria walcowania, rozważana w niniejszej pracy, wynika z różnych prędkości kitowych dwóch identycznych walców. Przedyskutowano wpływ asymetrii walcowania na rozkłady naprężeń i odkształceń, wygięcie materiału oraz modyfikację siły i momentu obrotowego wywieranego przez walce. Szczególną uwagę zwrócono na możliwość ukośnego wprowadzania materiału, które może występować w walcowaniu sekwencyjnym. Takie wprowadzanie materiału może częściowo zrekompensować jego wygięcie. Wyniki niniejszych obliczeń wskazują, że można znaleźć optymalne parametry w celu redukcji do minimum wygięcia blach i zmniejszenia siły i momentu sił wywieranych przez walce.