Recently I have spent a lot of time preparing my first paper related to PhD project. I hope it will be published in the 3D Materials Science conference proceedings. Its title is “A Toolbox for Geometric Grain Boundary Characterization” which means I have focused on short description of package of software tools developed by myself during last months. Writing this paper was a great opportunity to sum up my results and put them in the right order. We are now able to fully characterize a given boundary, recognize whether it belongs to any group of geometrically characteristic boundaries, provide boundary plane indices in coordinate systems of the first and the second grain. We can deal with both cubic and hexagonal close-packed polycrystals. We can also find all characteristic boundaries assuming certain misorientaion. For a given misorientations, such catalogues of characteristic boundaries are presented in the form of stereographic projections of boundary plane normals. We have used three different methods including analytical calculations, as well as purely numerical searches. Fortes decomposition and distance minimizations make it possible to directly introduce some uncertainties. Having several methods enables to perform various cross-checks which might be important for further investigations. Finally, obtained images can be linked to similar figures obtained experimentally.

In February, I passed exams of 'Fundamentals of solidification', 'Advanced scanning electron microscopy in materials science' and 'Transmission electron microscopy in materials science'.
I attended in PAS Seminars:
- MSc Eng. Jakub Kawalko: 'The use of methods and optical systems for measuring the stability of photo degradable materials',
- Prof. Antonio G. Checa: 'Multi-level approach to the study of microstructures fabricated by invertebrate molluscs',
- MSc Eng. Adam Debski: 'The enthalpy of formation of inter-metallic phases of lithium-silicon system'.
In that month, I also prepared a draft article under the title: ‘Early stages of recrystallization in ultra fine-grained AA1050 aluminium alloy’:
Abstract
Early stages of recrystallization in aluminium alloys are of considerable practical interest. They were observed for the AA1050 alloy. The samples were processed by equal channel angular pressing along route A up to six passes and then annealed for 1h at different temperatures to obtain different states of recrystallization. Microstructures have been analyzed in sections perpendicular to the extrusion direction, using scanning electron microscopy equipped with high-resolution electron backscattered diffraction facility.
The ECAP-deformed alloy contained a structure of flat grains with the spacing between high angle boundaries ranged from 100nm to 1µm. On annealing, structure coarsened and gets transformed into nearly equiaxed grains. Particular role in the rise of nuclei (at early stages of recrystallization) was attributed to migration of low-angle boundaries and cells coalescence. Later recrystallization stages were attributed to high-angle grain boundaries migration. These processes led to nearly equiaxed grains of similar size. It was documented that length of traces of low- and high- angle boundaries decrease with increasing time of annealing.
The average values of misorientation across both types of grain boundaries systematically grow. Orientation mappings showed that although orientations of new grains were widely scattered, they were not completely random.
Keywords : aluminium alloy, equal channel angular pressing, recovery and recrystallization, microstructure, EBSD

This month I took part in a training concerning use of the new WDS equipment. It seems that it will be useful in my PhD work since some X-ray peaks from elements in samples received from IOD overlap and are impossible to be distinguished by EDS. Rest of the month was spent on practicing use of the WDS.

In February, I focused on improving of my first scientific publication. I wrote about electroeposition of Sn-Zn and Sn-Zn-Mo layers from citrate solutions. I mainly describe the results of voltammetric studies. My paper has been already reviewed. I hope that my publication will be published soon. Then you will be able to know more about my research :)

The goal of my dissertation future will improve the structural properties of magnesium alloys AZ 31 and AZ91, by establishing certain microstructural conditions. The main topic of the paper will examine the impact of thermomechanical strengthening of molded magnesium alloy to improve their properties and processing parameters selection, providing an optimal ratio to improve the mechanical properties of the degree of deformation. This method of treatment is particularly interesting due to the predominant industrial process for producing magnesium alloy by die casting. The elimination of material defects, such as porosity which frequently arise during casting, will extend the use of magnesium alloy for a more responsible construction, for example in the aerospace industry.
In parallel, I dealt with two other issues relating to magnesium alloys. Examination of the previously undescribed magnesium balance of phosphorus will provide information about the suitability of this alloy additive. Planned are also trying to strengthen magnesium alloys - Lithium possible intermetallic phases with magnesium and phosphorus.
Another issue concerning the improvement of formability of magnesium alloy molded plastic processing methods, the use of ultrasound in the manufacture of magnesium. Tensile tests carried out so far samples from the simultaneous operation of ultrasound did not cause softening of the material, however, plans to build a position equipped with a head more powerful.