In april we have started the investigations of titanium after deformation by the ECAP technique. We've received two types of samples, one after 4 passes of ECAP route C and other after 8 passes. First some TEM investigations have been performed to reveal bimodal distribution of grain sizes as well as high concentration of lattice defects such as random dislocations and dislocation walls. Those random dislocations were particularly effective in distorting Kikuchi patterns. This in turn prevented us from getting proper diffraction sets for purpose of Orientation Microscopy investigations. With help came new heating holder that have been purchased in our institute allowing for precise annealing of thin foil. The annealing was done just to annihilate some of random dislocations, but not to cause any grain boundary migration. This allowed us to obtain better quality diffractions without changing actual structure of grains in the sample.

I have done analysis of obtained results for Al-Zr aluminium alloy. I have considered microstructural changes of the pre-deformed alloy during annealing at temperature in range 200°C -300°C. The grain size statistics have been done. Samples of the Al-Zr alloy were prepared to annealing at 50°C, 100°C, 150°C, 350°C and 400°C.
All the time I am writting my dissertation paper to have it completed in May.

The hardness measurements confirmed that investigated processing of Mg-AZ31 alloy strengthen the material. The micro-hardness test performed at two arrangements of the Knoop indenter longer axis, i.e. parallel to ED and parallel to RD, revealed anisotropy of mechanical properties of the examined pipe (Fig. 2). The Knoop’s hardness (HK) values were significantly higher for RD orientation of the longer axis of intender in comparison to the ED orientation of longer intender’s axis. For RD intender orientation average values of the HK were 66.4, 70.8, 86.5, 90.5, and 91.7 for deformations 0%, 5%, 13%, 28% and 50%, respectively.

Taking advantage of ERASMUS program I visited
Institute of Physics of Materials of the Academy of Sciences of the Czech Republic in Brno.
I spent there a week exchanging experience
concerning computation of grain boundary distributions.
I was also trying to learn basics of
atomistic simulations with LAMMPS package.
It allows computation of boundary energy for a given geometric arrangement.
This could help in interpretation of some results.

In the previous month, the focus was on the study of titanium dioxide substrates for photochemical method and FDTD simulation software of the particles no the cell front configuration.
The simulation stage included simulation set up preaparation and its advancing. Within the titania substrates investigation, the transmission, reflection an absorbacne spectra were measured. Next the absorption band edge was calculated. Optical constant and thickness were found from elipsometry measuremnts and fitting.