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Wybrane aspekty odkształcenia plastycznego na zimno stali AISI 304

Kurc-Lisiecka A.

Stal, Metale & Nowe Technologie

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2017

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nr 5-6

14--21

PL

Celem badań była analiza wybranych technicznych i strukturalnych aspektów odkształcenia plastycznego na zimno w procesie walcowania blach ze stali AISI 304. Metodyka badawcza obejmowała obserwacje struktury na mikroskopie świetlnym, badania własności mechanicznych określone w statycznej próbie rozciągania i pomiary twardości. Analizę składu fazowego przeprowadzono na podstawie badań rentgenograficznych. Potwierdzono analityczną zależność granicy plastyczności badanej stali od stopnia gniotu w procesie walcowania, co ma istotne znaczenie praktyczne dla tej technologii wytwarzania blach cienkich ze stali austenitycznej. Przeprowadzone badania metalograficzne i rentgenowska analiza fazowa wykazały, że w walcowanej na zimno stali austenitycznej przy większych stopniach gniotu zachodzi bezpośrednia przemiana fazowa (γĺα’).

EN

The aim of the study was to analyze the chosen technical and structural aspects of cold deformation in the rolling process of the AISI 304 steel sheets. The investigations included observations of the microstructure on a light microscope, a study of mechanical properties during static tensile tests and hardness measurements. The analysis of the phase composition was carried out by means of an X-ray diffractometer. It was found that the value of the AISI 304 steel’s tensile strength, yield point and hardness increase as the degree of its deformation increases, but simultaneously the value of elongation decreases. The analytic dependence of the yield point of the investigated steel on the deformation degree under cold rolling pressing process has been confirmed. The determination of this relation is crucial for the technology and precise shaping the properties of the sheet metal of austenitic steel under the production stage. The conducted metallographic investigations and X-ray phase analysis show that the plastic deformation under the cold working of austenitic steel AISI 304 induces the direct phase transformation (γĺα’) in its structure.

2

Structural and optical properties of pure and Ag doped ZnO thin films obtained by sol gel spin coating technique

Ali S. M., Farooq W. A., Baig M. R., Shar M. A., Atif M., Alghamdi S. S., Algarawi M. S., Naeem U. R., Aziz M. H.

Materials Science Poland

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2015

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Vol. 33, No. 3

601--605

EN

We have investigated the influence of Ag doping on zinc oxide thin films. Pure and Ag doped, preferentially oriented transparent zinc oxide thin films were prepared by sol gel technique on a glass substrate using diethyl amine as a stabilizer. The X-ray diffraction analysis revealed that the films with hexagonal wurtzite type structure were polycrystalline in nature with a preferred grain orientation in the 101 direction. The crystallite sizes decreased from 34 nm to 27 nm after silver doping. Both photoluminescence and optical transmission measurements showed that the band gap increased after the Ag doping. The structure and optical characterization studies clearly indicated the incorporation of Ag in ZnO. Hence, the observed increase in the optical band gap and decrease in crystallite size can be directly attributed to the effect of Ag ion incorporation into the ZnO lattice.

3

Effect Cd Doping on the Structural and Optical Properties of ZnO Thin Films

Najim J. A., Rozaiq J. M.

International Letters of Chemistry, Physics and Astronomy

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2013

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Vol. 10, iss. 2

137-150

EN

ZnO thin films with Cd/Zn nominal ratios of 0 %, 1 %, 3 %, 5 %, and 7 % and thickness of 0.7 μm were prepared by chemical spray pyrolysis. X-ray diffraction patterns showed that the films have polycrystalline structures and peaks matching the hexagonal ZnO structure. Crystallite sizes ranged from about 35 nm to 87 nm. As the doping concentration increased, full width at half maximum values decreased and crystallite sizes increased. The UV-Vis spectra of the ZnO:Cd films showed high transparency in the visible region. The optical band gap of the ZnO:Cd films decreased from 3.255 eV to 3.17 eV with increasing Cd doping concentration. The transition type was direct, thereby allowing transition. The ZnO:Cd thin films were annealed at 400 °C, and annealing treatment showed improvements in the properties of the derived films.

4

Influence of plastic deformation on structure and mechanical properties of stainless steel type X5CrNi18-10

Ozgowicz W., Kalinowska-Ozgowicz K., Kurc A.

Archives of Materials Science and Engineering

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2008

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Vol. 32, nr 1

37-40

EN

Purpose: The paper analyzes the influence of the degree of cold deformation on the structure and mechanical properties of austenitic stainless steel X5CrNi18-10. Design/methodology/approach: The investigations included observations of the structure on a light microscope, researches of mechanical properties in a static tensile test and microhardness measurements. The analysis of the phase composition was carried out on the basis of X-ray researches. In the qualitative X-ray analysis the comparative method was applied. Findings: Plastic deformation in deep drawing process of container from investigated austenitic stainless steel induced in its structure martensitic transformation γ → α'. Research limitations/implications: The X-ray phase analysis in particular permitted to disclose and identify the main phases on the structure of the investigated steel after its deformation within the range 10%÷50%. Practical implications: The analysis of the obtained results permits to state that the degree of deformation has a significant influence on the structure and mechanical properties of the investigated steels. Besides, a good correlation was found between changes of the structure and the effects of investigations of the mechanical properties. Originality/value: The analytic dependence of the yield point of the investigated steel on the draft degree in deep pressing process has been confirmed. Revealing this relation is of essential practical importance for the technology of sheetmetal forming of austenitic steel.

5

Wytwarzanie syntetycznych biomateriałów opartych na węglanie wapnia.

Jaegermann Z., Michałowski S., Karaś J., Polesiński Z.

Szkło i Ceramika

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2002

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R. 53, nr 4

3-10

PL

W artykule przedstawiono wyniki prac nad otrzymywaniem biomateriałów opartych na węglanie wapnia. W części literaturowej przedstawiono w zarysie dotychczasowe próby zastosowania naturalnych materiałów aragonitowych do wypełniania ubytków tkanki kostnej, a także uzyskania syntetycznych tworzyw kalcytowych. Niniejsza praca przedstawia rezultaty badań przerowadzonych w Instytucie Szkła i Ceramiki, obejmujących optymalizację sposobu otrzymywania spieczonego materiału opartego na węglanie wapnia z proszków zarówno kalcytowych jak i aragonitowych. Badano zależności właściwości fizycznych, takich jak: wytrzymałość mechaniczna na ściskanie, gęstość pozorna i porowatość otwarta od parametrów formowania i wypału ww. materiałów. Przeprowadzono także badania ich składu fazowego i tekstury. Ponieważ zarówno ocena właściwości jak i wstępne wyniki badań biozgodności otrzymanych tworzyw aragonitowych wypadły pozytywnie, uznano za celowe kontynuowanie rozpoczętych prac tak, aby w krótkim czasie możliwe stało się zastosowanie opracowanych materiałów w chirurgii kości.

EN

The paper presents the results of research on biomaterials based on calcium carbonate. The theoretical part of paper discusses current attempts of application of natural aragonite material for filling bone defects as well as the known ways of production of synthetic calcite materials. Experiments were focused on the method of manufacturing dense material based on both calcite and aragonite powders of calcium carbonate. The dependence between the physical properties of the materials: mechanical strength, bulk density and open porosity and forming and sintering parameters were investigated. Tests on the phase composition and structure properties were also provided. As both evaluation of the properties of the material and preliminary results of biological compatibility test were positive, the research will be continued aiming at prompt application of developed materials in bone surgery.