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Forging of PM Ti-6Al-4V alloy at the temperature above β-transus and high strain rate: modeling and trials in industrial conditions

Wojtaszek Marek, Zyguła Krystian, Łukaszek-Sołek Aneta, Jabłońska Magdalena, Stanik Rafał, Gude Maik

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 2

art. no. e102, 2023

EN

The results of the forging process in open dies of the powder metallurgy (PM) Ti-6Al-4V alloy, carried out at the temperature above β-transus and at a high strain rate were presented. As an initial material for the research relatively cheap elemental powders were used. This approach gives a real chance for the implementation of the developed technologies. As the range of phase transition temperature in titanium alloys is influenced also by the technology of their production, the β-transus temperature was estimated for the PM Ti-6Al-4V alloy. Finite element method (FEM) numerical analysis of the forging process at the temperature of 1000 °C and high strain rate was performed. The results obtained by the FEM modeling were verified under industrial conditions. The forging trials were made at the temperature of 1000 °C on a screw press operating at a speed of 250 mm s-1. For comparison, the alloy was also studied in as-cast and hot-rolled conditions, which is widely used as a feedstock. The influence of the method of manufacturing feedstock on the microstructure and selected properties of the forgings was determined. This approach allowed for a qualitative assessment of the PM material. The forging process in open dies of two different feedstocks led to the production of forgings with a uniform and similar lamellar microstructure. Thus, it was shown that the heating conditions, the parameters of the forging process, and the method of cooling the product after forging have a decisive influence on the microstructure condition of the forgings shaped in the temperature range of the β phase.

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Effect of the conversion of the plastic deformation work to heat on the behaviour of TWIP steels: a review

Jabłońska Magdalena

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 2

art. no. e135, 2023

EN

The study discusses the subject of a temperature change of TWIP steels during their deformation as a result of a conversion of the plastic deformation work into heat, based on a literature review and the authors' own research. The methods of measuring or modelling the changes of these temperatures are presented. It also points out that the heat generated during plastic deformation of TWIP steels has higher values than in the case of conventional steels, due to their higher yield stresses and limit strains. The heat has a very important effect on the microstructure of the deformed material and thus also on its properties. Its high increase can lead to e.g. a change of the deformation mechanism from twinning to dislocation glide, which is also connected with worse workability and thus also the energy consumption of the bodywork elements. On the basis of the selected literature works, the study determines the possible microstructural changes of TWIP steels related to the generated heat and demonstrates that materials with similar chemical compositions can behave differently at high deformation rates.

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Electromyographic assessment of muscle fatigue after the Biering–Sorensen test in subjects with low back pain who underwent the McKenzie treatment

Jabłońska Magdalena, Mączyński Jacek, Fryzowicz Anna, Ogurkowska Małgorzata B.

Acta of Bioengineering and Biomechanics

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2021

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Vol. 23, no. 3

87--96

EN

Purpose: Chronic low back pain is a common disorder affecting about 80% of the population, caused by a disorder in the muscular system. The main aim of this study was to assess muscle fatigue during the Biering–Sorensen Test in people with chronic low back pain who underwent the McKenzie treatment. Methods: Tests were conducted on 19 men (mean age of 41.4 years) with chronic non-specific lumbar-sacral pain syndrome, working in the seated position in front of a computer. Assessment of changes in fatigue of erector spinae, gluteus maximus and biceps femoris using surface electromyography during the Biering–Sorensen Test and subjective pain assessment using Visual Analog Scale were conducted on three test dates. Time-frequency representation of the electromyographic signal (Fourier transform) was used for the examination of muscle fatigue. The McKenzie method of diagnosis and therapy was applied before and between the tests. Results: The McKenzie therapy resulted in increased endurance (test duration) of the examined spinal muscles between the 1st and 3rd test date (p = 0.043), and a systematic decrease in pain assessment on the three test dates (p = 0.000–0.004). Correlations were obtained between slope coefficients of the simple regression of median frequency of electromyographic signals on the one hand and duration of the BST (p = 0.000–0.012) and anthropometric parameters (body mass, height and body mass index, p = 0.001–0.020) on the other. Conclusions: The McKenzie method is an effective tool in reducing the level of lumbar pain and improving muscle endurance.

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Electromyographic evaluation of selected muscles during active hip extension in men treated McKenzie method

Jabłońska Magdalena, Fryzowicz Anna, Ogurkowska Małgorzata Barbara

Acta of Bioengineering and Biomechanics

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2020

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Vol. 22, no. 3

23--31

EN

Purpose: The aim of this study was to evaluate objective results of short-term treatment with the use of electromyography and to determine changes in muscle recruitment during the prone hip extension test in individuals with chronic low back pain who underwent the McKenzie treatment. Methods: The studied group consisted of 17 male office workers aged 33–55 who underwent two experimental sessions comprising of 3 measurements and the McKenzie method of mechanical diagnosis and therapy. Electromyographic examination of selected muscles was performed during the test in order to assess changes in their activity before and after the McKenzie method and the Visual Analogue Scale was used to assess the level of pain. Results: There was a tendency towards significance at the beginning of activation between the first and second test for the left erector spinae muscle ( p = 0.0684). In 18% of patients, the onset activation time decreased, which is indicative of correct direction of changes. No statistically significant changes were observed in the remaining muscles. Statistical significance ( p = 0.0131) was observed between the first and third test for the left erector spinae muscle. A decrease in the onset activation time was observed in 75% of the subjects. Effectiveness increased by as much as 57%. The level of pain decreased in the third test compared to the first one ( p = 0.0240). However, the change in pain sensations between the first and second test was not statistically significant. Conclusions: The study showed objective changes in the activation sequence of selected muscles and subjective changes in pain following short term McKenzie therapy.

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Nowe wymagania oznakowania EU Ecolabel dla bibułki tissue i produktów z bibułki tissue

Jabłońska Magdalena

Przegląd Papierniczy

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2019

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R. 75, nr 2

103--106

PL

Oznakowanie ekologiczne EU Ecolabel jest dobrowolnym programem Unii Europejskiej, którego celem jest promocja między innymi wyrobów papierniczych charakteryzujących się mniejszym negatywnie oddziaływaniem na środowisko, niż inne produkty z tej samej grupy wyrobów niespełniające wymagań oznakowania ekologicznego UE. Certyfikowanie produktu potwierdza efektywniejsze wykorzystanie zasobów naturalnych, a co za tym idzie podniesienie poziomu ochrony środowiska i efektywności ekologicznej. W artykule przedstawiono nowe wymagania oznakowania EU Ecolabel dla bibułki tissue i produktów z takiej bibułki.

EN

The EU Ecolabel is a voluntary scheme of the European Union, which promotes paper products with a positive impact on the environment than others of the same group of products, which contributes to the efficient use of natural resources, and thus raise the level of environmental protection and eco-efficiency. The new ecological criteria of the EU Ecolabel for tissue paper and tissue products have been presented in this article.

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The influence of holmium on catalytic properties of Fe or Cu-modified vermiculites

Samojeden Bogdan, Grzybek Teresa, Kowal Joanna, Szymaszek Agnieszka, Jabłońska Magdalena, Gläser Roger, Motak Monika

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 6

1484--1495

EN

Natural layered clay, vermiculite, was modified and tested as catalyst for the selective catalytic reduction of NOx with ammonia (NH3-SCR). Its modification included the application of the blowing agent (azodicarbonamide), acid treatment and pillaring with Al2O3. Active phase (transition metals: Cu or Fe) was introduced via impregnation. The obtained materials were characterized by N2 sorption (texture), XRD (structure), DR-UV-Vis (oxidation state and aggregation of the active phase), H2-TPR (reducibility of the active phase), in situ DRIFTS (types of adsorbed species due to contact of the sample NH3) and NH3-TPD (type/strength of the acidic sites). The initial modification procedures (treatment with azodicarboamide) resulted in the increase of specific surface area of vermiculite. The introduction of transition metal ions provided a significant amount of acidic sites. The promoting impact of holmium was confirmed by the increased strength of the sites. The highest catalytic activity was exhibited by the sample Fe-containing vermiculite and doped with Ho.

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Wpływ ściskania na mikrostrukturę i twardość stali wysokomanganowej

Tomaszewska Agnieszka, Jabłońska Magdalena, Tkocz Marek

Hutnik, Wiadomości Hutnicze

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2019

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Vol. 86, nr 3

72--76

PL

Aktualnie wiele ośrodków badawczo-naukowych koncentruje swe prace w obszarze nowych stali wysokomanganowych z grupy AHSS. Stale te mogą stać się konkurencyjne w stosunku do stosowanych, tradycyjnych materiałów metalicznych. Występująca w tych stalach synergia właściwości mechanicznych stanowi nową jakość w stalowych materiałach konstrukcyjnych i istotnie zmienia możliwości projektowania i wytwarzania elementów konstrukcyjnych pojazdów mechanicznych. W pracy dokonano oceny struktury i właściwości dwóch gatunków stali wysokomanganowej austenityczno- ferrytycznej po odkształceniu plastycznym. Stale posiadały zróżnicowaną zawartość węgla, manganu i aluminium. Celem pracy było określenie wpływu parametrów odkształcenia w procesie ściskania na właściwości obu gatunków stali. Analizę struktury przeprowadzono wykorzystując techniki mikroskopii świetlnej i skaningowej. Oceny właściwości dokonano na podstawie pomiarów twardości.

EN

Recently many research centres focus in the area of new high manganese steel from the AHSS group. These steels can become competitive in relation to the traditional, metallic materials used. The synergy of mechanical properties existing in these steels constitutes a new quality in steel construction materials and significantly changes the possibilities of designing and manufacturing of construction elements of motor vehicles. In the paper, two grades of high-manganese steels after a plastic deformation were studied. Steel grades with an austenitic-ferritic structure with various contents of carbon, manganese and aluminum were selected for the studies. The main goal of the work was to determine the influence of deformation parameters on the properties of both examined steel grades. The structural analysis was carried out using optical and scanning microscopy techniques. The properties were evaluated on the basis of hardness measurements.

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Wpływ parametrów obróbki cieplnej na strukturę i właściwości mosiądzu MO58

Tomaszewska Agnieszka, Jabłońska Magdalena

Hutnik, Wiadomości Hutnicze

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2019

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Vol. 86, nr 5

173--178

PL

Miedź i stopy miedzi pomimo wieloletniego udziału w nauce i przemyśle w dalszym ciągu cieszy się ogromnym zainteresowaniem, głównie ze względu na swoje wyjątkowe właściwości, np. odporność na korozję czy bardzo dobre przewodnictwo cieplne oraz elektryczne. Jednym z powszechnie stosowanych stopów na elementy armatury przemysłowej, części do przewodów rurowych a także do armatury wodno-kanalizacyjnej jest znany i opanowany technologicznie mosiądz CuZn40Pb2. Obecnie dąży się w kierunku podejmowania badań nad nowymi stopami o ograniczonych stężeniach ołowiu. Należy przypuszczać, że w przyszłości dopuszczalna będzie w mosiądzach pewna zawartość ołowiu, a jej poziom będzie zróżnicowany w zależności od zamierzonego zastosowania. Niemniej jednak na chwile obecną nadal w powszechnym użytku jest wiele stopów tzw. ołowiowych. W pracy dokonano oceny struktury i właściwości mosiądzu w gatunku MO58 po zastosowanej obróbce cieplnej. Celem pracy było określenie wpływu różnych parametrów wyżarzania w zakresie temperatury obróbki plastycznej na właściwości stopu. Analizę struktury przeprowadzono wykorzystując techniki mikroskopii świetlnej. Oceny właściwości dokonano na podstawie pomiarów twardości.

EN

Copper and copper alloys, despite their longstanding participation in science and industry, continue to enjoy great interest, mainly due to their unique properties, e.g. corrosion resistance or very good thermal and electrical conductivity. One of the commonly used alloys for elements of industrial fittings, parts for pipelines as well as for water and sewage fittings is the well-known and technologically controlled CuZn40Pb2 brass. Currently, the aim is to undertake research on new alloys with limited concentrations of lead. It should be assumed that in the future a certain content of lead will be allowed in brass and its level will vary depending on the intended use. Nevertheless, at the present moment there are still many so-called lead. The paper assesses the structure and properties of brass in MO58 grade after heat treatment. The aim of the study was to determine the influence of various annealing parameters on the properties of the alloy. The analysis of the structure was carried out using light microscopy techniques. The properties were evaluated on the basis of hardness measurements.