Monday, 31 December, 2012, 23:48
Posted by Piotr Drzymala
On 3-4 December 2012, participated in the seminar - Join PhD Seminar - held in Radeburg, Germany.
The organizers of the seminar were: Enano group of the Institute of Materials Science and Engineering at the Technical University of Dresden and the Institute of Metallurgy and Materials Science in Krakow.
The main objective was to present seminars by the participants' own research results, often within the scope of the PhD dissertation of the future, and their discussion in an interdisciplinary group of young scientists.
During the seminar I gave a lecture under the title: Improvement of properties of Mg alloys construction-Importance of Microstructure. The paper presents the evolution of the texture for the basal plane (0001), lateral (10-10) and pyramidal (10-11). In the initial state after extrusion showed a preferential orientation crystallites and increase the degree of distortion caused strong texture. As a result of the manufacturing process of the first basal plane was oriented crystallites {0001} <11-20> direction parallel to the extrusion. At the same time the intensity of the angular range of reflection on the pole figure was broad and vertically stretched, which is clearly visible for the other two planes: prismatic and pyramidal. This vertical scattering intensity maximum corresponds to the direction of extrusion of the sample. Pole figure analysis (0001) of the starting material (0% deformation) showed that the crystal c axis is arranged in the normal direction (ND) and horizontally (TD) with respect to the measured sample. When the value was 28% of the density of crystallites reorientation of raising the density of the underlying planes of the poles {0001} direction ND with respect to the RD. During cold rolling of a grain parallel to the c-axis direction of the activation process of deformation twinning favor the {10-12} planes. Analysis of the images of the microstructure showed that the critical stress for the twinning plane {10-12} is reached already in the first stage of deformation. A further increase in the degree of deformation caused stronger texture {0001} in direction ND, until cracks appear stage. At the same time, the number of twins and increased fragmentation of microstructure occured. There was a trend deviation of basal texture component {0001} about 15 ° from the direction ND to the direction of TD. This deviation could not be used due to sample preparation, which was confirmed by examining the texture on the surface normal to the axis of the tube, as well as on the surface to be analyzed metallography. This type of texture is characteristic of some of the processes forming of magnesium alloys, including extrusion and rolling, where in addition to the base slip, twinning and pyramidal slip, slip increases <c+a> nonbasal activity. Additional studies confirmed the trend deviation texture pole peak (0001) from the radial direction (normal) to the transverse direction. This phenomenon is attributed to the nonbasal slip systems in the hexagonal structure and twinning.
On 5-6 December 2012 we participated in Training - Nano-scale Materials and Advanced Characterization Techniques-held in Dresden, Germany.
Training was organized by the Institute of Fraunhofer in Dresden, supported by FEMS - the Federation of European Materials Societies.
The main objective of training was to broaden the knowledge of participants in the field of nanomaterials and their nanoanalizy, so in the course of lectures delivered by experts in the wider physical and chemical analysis of materials.