Scientific blog
May 
Wednesday, 4 June, 2014, 08:50
Posted by Piotr Drzymala
In this study we adopted the Rodriguez parameterization for description of preferred twin variants in the orientation space. The Rodriguez-Frank orientation space for hexagonal 6/mmm lattice filled with ca. 〖10〗^4 vectors is presented in Fig. 2 [10,11]. The main axes of this coordinate system (R1, R2 and R3) correspond to sample's coordinate system (X, Y, Z). The R1 and R2 values are restricted to range ±1 and R3 is restricted to range ±(2-√3). The presented vectors have minimum length of 0.7 and can be considered as crystallites' orientations transforming sample coordinate systems to crystal ones by the rotations around these vectors by angles between 69.98° and 93.84° [11]. The orientation distribution presented in Fig. 1 is characteristic for extruded hexagonal metals and alloys (like Ti and Mg and its alloys [6,12]).
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May report 
Tuesday, 3 June, 2014, 09:58
Posted by Zbigniew Starowicz
Recently, I was concentrated on colloidal solutions. I obtained new suspension of 100-120nm nanoparticles with high concentration. I tried other solutions as well. But only with this mentioned I obtained clearly visible change in appearance of silicon wafer after particles deposition. The solution had to be even disolved to enable control of deposition process.
SEM measurements revealed 4,5 and 7% of surface coverage, unfortunaltely with significant percentage of aggromerated particles. Measured reflection after NPs deposition law lowered considerably when compare to silicon wafer without the nanoparticles. Obtained reflection was lower, than expected from FDTD sumulations.
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J Kawalko April 
Saturday, 10 May, 2014, 14:23
Posted by Jakub Kawalko
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.
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PhD report (April 2014) J.Poplewska  
Thursday, 8 May, 2014, 10:19
Posted by Jagoda Poplewska
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.
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April 
Wednesday, 7 May, 2014, 16:37
Posted by Piotr Drzymala
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.
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