Scientific blog
PhD report (March 2011) Marta Gajewska 
Thursday, 7 April, 2011, 13:33
Posted by Marta Gajewska
My research:

Composite powders - 7475 aluminium alloy powder with 10 wt.% and 20 wt.% addition of aluminum nitride powder subjected to high energy ball milling - were compacted in a VEB 40 hydraulic uniaxial press in a mould placed in a vacuum and heated using a high frequency generator. Discs about 5mm thick, 20 mm in diameter were obtained after hot pressing in a vacuum of 10-2 bar, at a pressure of 600 MPa and temperature of 380oC.
The microstructure of the hot compacted composites was characterized using an FEI E-SEM XL30 scanning electron microscope and a Tecnai G2 F20 (200kV) transmission electron microscope equipped with an integrated EDAX system. Thin foils for TEM investigations were prepared by mechanical polishing, dimpling with a Gatan Dimple Grinder (Model 656) and finally ion Ar milling with a Leica EM RES101 system.
Microhardness Vickers measurements were performed using a CSM-Instruments tester.

Seminars/meetings:

Third meeting of “Local Composite Platform”:
- presentation on ”Mechanical properties of metal-ceramics cast composites” by Pawel Kurtyka
IMMS seminars:
- “Investigations on the catalytic Au/TiO2 modelsystem” by Piotr Bobrowski
- “Atomistic simulations of the process of phase separation in the Fe-Cr system” by Rafal Abram,
- “Influence of technological factors on the wettability of soldering” by Artur Kudyba.

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PhD report (March 2011) J.Poplewska 
Thursday, 7 April, 2011, 12:51
Posted by Jagoda Poplewska
1. Attending in seminars:
- M. Sc. Eng. Piotr Bobrowski: ‘Investigations on the catalytic Au/TiO2 modelsystem’
- M. Sc. Eng Rafal Abram: ‘Atomistic simulations of the process of phase separation in the Fe-Cr system’;
- M. Sc. Eng Artur Kudyba: ‘Influence of technological factors on the wettability of soldering’;
- Professor Pawel Zieba: ‘Mass and charge transport in polycrystalline materials’;
- Associate Professor Marek Faryna: ‘Correlation between ceramics microstructure and functional properties’;
- Professor Henryk Paul: ‘Instability of plastic flow and their role in texture transformations in fcc metals’;
- Associate Professor Lidia Litynska-Dobrzynska: ‘Development of aluminium alloys’.

2. Discovering of Mendeley possibilities

3. Introduction to the scanning electron microscope to analyze the chemical composition using patterns. The analysis of chemical composition of aluminum-scandium alloy purchased in China. Result of the analysis is consistent with the certificate of purity (Al-2% Sc). This alloy will be subjected to chemical modifications in order to obtain materials of the program of research (Al-Sc and Al-Mg-Sc).

4. Surface preparation and execution of samples analysis in scanning electron microscope aluminum alloy with addition of magnesium and zirconium to confirm the well-selected temperature of homogenization. Earlier observations of the microstructure on the optical microscope revealed the existence of precipitates or voids. Analysis of chemical composition on the scanning electron microscope indicated that these are dispersoids Al3Zr. They are due to the fact that the solubility of zirconium in aluminum is very small, hence they form a separation, which are fairly distributed in the material. The next step is choosing the appropriate temperature heat treatment - this time, supersaturation and aging - based on literature data and own observations. Samples of the Al-Mg-Zr after homogenization were cut into smaller samples, which will undergo further treatment - each at different temperatures. Based on observation of the microstructures will be selected the most appropriate process parameters.

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PhD report (March 2011) 
Thursday, 7 April, 2011, 11:39
Posted by Katarzyna Stan
Main studies carried out during March:

- Microhardness measurements of the melt spun ribbons. As a result large scatter of data was obtained due to inhomogeneous microstructure of the ribbons.
- SEM imaging of the melt spun ribbons cross-section confirmed change in microstructure during changing casting condition (wheel speed). With faster cooling rates more areas with homogenous microstructure occurs in the ribbon. Also chemical analysis of phases present in the ingot was performed. Three different phases were found.
- Icosahedral phase indentification– based on electron diffraction patterns.
- Investigations of icosahedral phase decomposition during thermal treatment (TEM, XRD) – based on the obtained results probably two step decomposition trough the intermediate phase take place.
- Casting of two new alloys with zirconium and silicon addition.

Awards:
1st prize for the best Ph.D student’s abstract: TEM study of quasicrystals in Al-Mn-Fe melt - spun ribbon for the upcoming XIVth International Conference on Electron Microscopy (sponsored by Polish Society for Microscopy).

Participation in seminars:
- M. Sc. Eng. Piotr Bobrowski: ‘Investigations on the catalytic Au/TiO2 modelsystem’
- M. Sc. Eng Rafal Abram: ‘Atomistic simulations of the process of phase separation in the Fe-Cr system’;
- M. Sc. Eng Artur Kudyba: ‘Influence of technological factors on the wettability of soldering’;


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PhD report (March 2011) H.Kazimierczak 
Thursday, 7 April, 2011, 08:29
Posted by Honorata Kazimierczak
In March 2011 I begun the study of hydrogen release on different surfaces from citrate solutions. Surface-limited kinetics of hydrogen release are derived for arbitrary surface coverage (Fe, Zn,Sn).

For this purpose, first, it was necessary to prepare the surface of the samples for further investigation . Therefore on 1-3.03.2011 and 7-11.03.2011 I ran the process of potentiostatic deposition of tin and zinc from citrate bath on samples of steel (previously etched in a solution of oxalic acid with hydrogen peroxide and defatted in acetone). Then I prepare a series of citrate baths. Electrolytes were prepared with analytical grade reagents and deionized water. A range of solutions with varying citrate concentration and pH were prepared by dissolving appropriate amounts of C6H5Na3O7.2H2O and C6H8O7.H2O, adjusting the pH using H2SO4 and NaOH and mixing of solutions. The citrate concentration was varied between 0,1 M and 0,7 M and the pH between 1.0 and 9.0.

Subsequently, on from 14 to 31 march 2011 I conducted research of hydrogen release from selected baths on surfaces of steel, tin and zinc . the experiment were carried out and controlled by means of PARSTAT 2273 potentiostat. Voltammetric curves were determined under various hydrodynamic conditions by the rotating disc electrode technique.

The results of all carried out tests, and plans for further research were discussed in detail with the tutor Prof. Associate. dr hab. Piotr Ozga.

In March 2011 I also attended in the following seminars:
- M. Sc. Eng. Piotr Bobrowski: ‘Investigations on the catalytic Au/TiO2 modelsystem’ (4.03.2011)
- M. Sc. Eng Rafal Abram: ‘Atomistic simulations of the process of phase separation in the Fe-Cr system’ (11.03.2011)
- Professor Pawel Zieba: ‘Mass and charge transport in polycrystalline materials’(11.03.2011)
- Associate Professor Marek Faryna: ‘Correlation between ceramics microstructure and functional properties’;(18.03.2011)
- Professor Henryk Paul: ‘Instability of plastic flow and their role in texture transformations in fcc metals’(18.03.2011)
- M. Sc. Eng Artur Kudyba: ‘Influence of technological factors on the wettability of soldering’(25.03.2011)
- Associate Professor Lidia Litynska-Dobrzynska: ‘Development of aluminium alloys’ (25.03.2011).


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PhD report (March 2011) Grazyna Kulesza 
Wednesday, 6 April, 2011, 11:59
Posted by Grazyna Kulesza
Participation in seminars IMMS PAS:
-Lecture M. Sc. Eng. Piotr Bobrowski: ‘Investigations on the catalytic Au/TiO2 modelsystem’ (03/04/2011)
-Lecture M. Sc. Eng Rafal Abram: ‘Atomistic simulations of the process of phase separation in the Fe-Cr system’ (11/03/2011)

Participation in conferences and symposiums:
‘Second Symposium on Photovoltaics and Transparent Electronics – Development Prospects’
24-27.03.2011 in Swieradow-Zdroj
Presentation entitled: ‘Chemical preparation of the active-surface in the manufacture of photovoltaic cells and modules’.
Research was done in the interdisciplinary doctoral program in the field of materials science in English-speaking, the project implemented POKL.04.01.01-00-004/10 IMMS PAS.

Awards:
1st place in the competition for the best speech for the work of ‘Chemical preparation of the active-surface in the manufacture of photovoltaic cells and modules’ (Swieradow-Zdroj 24-27.03.2011)

Researches already performed:
-Implementation of the texture on monocrystalline silicon (Cz-Si) in KOH solution using diacetone alcohol (DAA) with a high boiling point.
-Choosing the composition of the mixture on the basis of commonly used mixtures containing isopropyl alcohol. Examination of the composition.
-Examine the effects of reaction time on the so-prepared solutions. Observation of alkaline-made textures under microscope and the analysis of surface morphology using scanning electron microscopy techniques.
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