Scientific blog
PhD report (January 2013) M. Gajewska 
Tuesday, 5 February, 2013, 15:53
Posted by Marta Gajewska
Last month I’ve made a second attempt towards in situ formation of AlN reinforcement in aluminium matrix. The experiment involved melting of aluminium in Balzers type induction furnace, and then, after removal of surface oxide layer, introduction of nitrogen-bearing substrate (in form of a green compact) to the metallic melt. Unfortunately, apart from eddy currents, there was no possibility of mixing the melt, which was the reason why the substrates remained on the surface of aluminium. As a result, aluminium nitride was found only in the surface layer of the material.
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January 2013/ Piotr Bobrowski 
Monday, 4 February, 2013, 15:36
Posted by Piotr Bobrowski
This month I changed the way I use FIB. Instead of running 3D-EBSD measurements I was focused on learning how to prepare a sample for TEM. This knowledge may be useful in the future because it may be necessary in T-EBSD measurements. They are based on detection of diffracted electrons that were transmitted through a thin sample. Such experiments are carried out in SEM. They may improve special resolution of the EBSD technique.
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PhD report Feb2013PC 
Sunday, 3 February, 2013, 09:02
Posted by Pawel Czaja
We carried out work on editing and polishing of the manuscript. It has finally been sent out to other co-authors for final check and comments. Along side this task we cast new alloys with different compositions, which included mastering the art of arc melting.
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January report 
Sunday, 3 February, 2013, 08:16
Posted by Zbigniew Starowicz
During last months I was studing carefully the literature and lectures accessible in the net.
Also I spent a lot of time for prepring for exams
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January 
Saturday, 2 February, 2013, 10:10
Posted by Piotr Drzymala
We considered possible slip and twinning systems for any desired orientation of the crystal. Depending on the adopted strain tensor, which can describe simple compression or rolling, different values are obtained for the selected orientation of the stresses described by Euler angles. Through the rotation of vectors of the unit cell is an altered relationship between the angular direction on the stress and possible slip systems. In the first step a rate of deformation (macroscopic) is assumed, an equivalent strain tensoris calculated using the approach full constrains (FC) initial deformation for each orientation, represented as a cube with a side equal to 10 °. Five elements considered combinations of 7-elements selected collections slip, the choice was made by taking into account the largest shear stress for slip data in relation to the adopted apriori critical shear stress. Then solved (nk) = (7 5) = 21 systems of linear equations and five function minimized the sum of the products of the critical shear stress and deformation modules for data of slip systems. With so selected strains five nonlinear equations were solved amount of an unknown scalar product of the stress tensor and tensor Schmidt (hence the notation Lequeu), raised to the power of n <= 20 By minimizing the corresponding function is possible to approximate the solution of these equations and calculating the stress tensor and the setting of Secant visco-plastic modules susceptibility grains. The problem arose when calculating the inverse matrix of these modules due to the generally poor conditioning of the matrix, so their inverse matrices can contain large numerical errors.
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