Wyniki wyszukiwania - BazTech

1

Czy modyfikacja stopu aluminium jest zawsze skuteczna?

Wróbel J.

Przegląd Odlewnictwa

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2025

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Vol. 75, nr 3-4

100--104

PL

Modyfikacja stopu aluminium ma bardzo istotny wpływ na uzyskanie zwiększonych właściwości mechanicznych wytwarzanego stopu. W celu jej przeprowadzenia stosuje się najczęściej preparaty zawierające tytan, bor lub oba te pierwiastki jednocześnie, a także związki zawierające metale ziem rzadkich. W omawianym artykule przedstawiono szczegółowo próby technologiczne, podczas których odlane aluminium z gatunku EN-AC-44300 podano zabiegowi modyfikacji. Miała ona służyć polepszeniu wytrzymałości na rozciąganie (Rm) i plastyczność odlewów (Rp02). W toku badań wytworzonego materiału i jego oceny okazało się jednak, iż zabieg modyfikacji nie przyniósł oczekiwanych rezultatów. Badania próbek modyfikowanego stopu wykazały ponad 40% spadek wytrzymałości (Rm), a także prawie 27% spadek plastyczności (Rp02) oraz 3% spadek twardości. Analiza wyników pozwala postawić wniosek, iż to sposób pobrania próbek do badań lub zastosowany rodzaj modyfikatora odpowiadają za niekorzystny wpływ na otrzymane wyniki.

EN

Modification of the aluminum alloy has a very significant impact on obtaining increased mechanical properties of the produced alloy. In order to carry it out, preparations containing titanium, boron or both of these elements at the same time, as well as compounds containing rare earth metals, are most often used. The discussed article presents in detail technological tests during which cast aluminum of the EN-AC-44300 grade wassubjected to a modification procedure. It was to serve to improve the tensile strength (Rm) and yield strength of castings (Rp0.2). However, in the course of tests of the produced material and its evaluation, it turned out that the modification procedure did not bring the expected results. Tests of the modified alloy samples showed over 40% decrease in strength (Rm), as well as almost 27% decrease in yield strength (Rp0.2) and 3% decrease in hardness. Analysis of the results allows us to conclude that the method of taking samples for testing or the type of modifier used are responsible for the adverse effect on the obtained results.

2

Information Retrieval in Friction Stir Welding of Aluminum Alloys by using Natural Language Processing based Algorithms

Mishra Akshansh

Welding Technology Review

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2024

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R. 96

147--154

EN

Text summarization is a technique for condensing a big piece of text into a few key elements that give a general impression of the content. When someone requires a quick and precise summary of a large amount of information, it becomes vital. If done manually, summarizing text can be costly and time-consuming. Natural Language Processing (NLP) is the sub-division of Artificial Intelligence that narrows down the gap between technology and human cognition by extracting the relevant information from the pile of data. In the present work, scientific information regarding the Friction Stir Welding of Aluminium alloys was collected from the abstract of scholarly research papers. For extracting the relevant information from these research abstracts four Natural Language Processing based algorithms i.e. Latent Semantic Analysis (LSA), Luhn Algorithm, Lex Rank Algorithm, and KL-Algorithm were used. In order to evaluate the accuracy score of these algorithms, Recall-Oriented Understudy for Gisting Evaluation (ROUGE) was used. The results showed that the Luhn Algorithm resulted in the highest f1-Score of 0.413 in comparison to other algorithms.

3

Odlewanie felg samochodowych ze stopu AlSi7Mg

Piątkowski Jarosław, Chowaniec Leszek

Przegląd Odlewnictwa

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2024

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Vol. 74, nr 7-8

218--220

PL

Felgi ze stopów aluminium można produkować metodami: kucia, skręcania, odlewania grawitacyjnego i pod niskim ciśnieniem. Niezależnie od zalet i wad każdej z tych technologii, najczęściej stosowanym sposobem ich wytwarzania jest odlewanie niskociśnieniowe (do 0,2 MPa). Zapewnia ono uzyskanie wyrobów o dobrej jakości, wymaganych właściwościach mechanicznych i narzuconych przez klienta kształtach, przy relatywnie niskim koszcie produkcji. Odlewanie felg pod niskim ciśnieniem można umownie podzielić na procesy główne (topienie, odlewanie, obróbka cieplna i mechaniczna, polerowanie, lakierowanie) oraz pomocnicze (kontrola międzyoperacyjna, ocena wizualna, przygotowanie form odlewniczych, zarządzanie surowcami i logistyka wewnątrzzakładowa). Odlewanie felg samochodowych przedstawiono na przykładzie Superior Industries Production Poland sp. z o.o. Stalowa Wola.

EN

Aluminum alloy rims may be manufactured by the following methods: forging, twisting, gravity casting and low-pressure casting. Regardless of the advantages and disadvantages of each of these technologies, the most commonly used method of manufacturing them is low-pressure casting (up to 0.2 MPa). It ensures obtaining products of good quality, required mechanical properties and shapes imposed by the customer, at a relatively low production cost. Low-pressure casting of rims can be conventionally divided into main processes (melting, casting, heat and mechanical treatment, polishing, painting) and auxiliary processes (inter-operational inspection, visual assessment, preparation of casting molds, raw material management and in-house logistics). Casting of car rims is presented on the example of Superior Industries Production Poland Sp. z o.o. Stalowa Wola.

4

Zintegrowane smarowanie i hartowanie przy tłoczeniu na gorąco stopu aluminium utwardzanego wydzieleniowo

Jemielniak Krzysztof

Mechanik

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2024

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R. 97, nr 5-6

52

PL

Wadą typowych stopów aluminium (SA) jest słaba formowalność w temperaturze pokojowej. W celu przezwyciężenia tego problemu zaproponowano utwardzanie wydzieleniowe po formowaniu jako tłoczenie SA na gorąco.

5

Effect of higher contents of manganese and magnesium on the mechanical properties of twin-roll cast aluminium alloy EN AW-8011

Pavlasek Lukas, Bernatik Martin, Trojan Jan

Materials Science and Welding Technologies / Technologie Materiałowe i Spawalnicze

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2024

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Vol. 68, No. 4

art. no. 3

EN

Because of their excellent formability and sufficient mechanical properties, aluminium alloys based on an aluminium–iron–silicon system are very popular materials, commonly used in the production of thin foils. Alloy EN AW-8011 contains approximately 0.50–1.00 wt. % of iron and 0.40–0.80 wt. % of silicon. The other elements, including manganese and magnesium, are present only as impurities. However, these two elements are generally very effective enhancers of mechanical properties. Due to their very low concentrations in alloy EN AW-8011, the influence of manganese and magnesium on mechanical properties is often overlooked. In the research work discussed in the article, the properties of two Twin-Roll cast aluminium alloy EN AW-8011 containing various amounts of manganese and magnesium were investigated using optical microscopy, scanning electron microscopy (SEM), energy dispersive X-ray analysis (EDX) and tensile tests. The test results revealed that higher contents of magnesium and manganese significantly changed the mechanical properties of the alloy.

PL

Ze względu na swoją doskonałą odkształcalność i odpowiednie właściwości mechaniczne, stopy aluminium na bazie układu aluminium – żelazo – krzem są bardzo popularnymi materiałami stosowanymi w produkcji cienkich folii. Stop EN AW-8011 zawiera około 0,50–1,00% żelaza oraz 0,40–0,80% krzemu. Pozostałe pierwiastki, w tym, m.in. mangan oraz magnez, występują jedynie w postaci zanieczyszczeń, chociaż na ogół bardzo skutecznie poprawiają właściwości mechaniczne stopów. Ze względu na bardzo niskie stężenia manganu i magnezu w stopie EN AW-8011, ich wpływ na właściwości mechaniczne stopu jest często pomijany. Artykuł przedstawia badania właściwości dwóch, uzyskanych metodą Twin-Roll, odlewanych stopów aluminium EN AW-8011 o różnej zawartości manganu i magnezu. Badania obejmowały obserwacje z użyciem mikroskopu optycznego oraz skaningowego mikroskopu elektronowego, analizy z zastosowaniem spektroskopii rentgenowskiej z dyspersją energii oraz próby rozciągania. Badania wykazały, iż większa zawartość magnezu oraz manganu prowadzi do istotnych zmiany właściwości mechanicznych ww. stopu.

6

Investigation of coated and uncoated carbide cutting tool wear in dry turning of en aw 2007 aluminum alloy

Leksycki Kamil, Patil Gauravkumar Himmatrao, Małecka Joanna, Cagan Cinar Suleyman, Dąbrowski Karol

International Journal of Applied Mechanics and Engineering

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2024

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Vol. 29, no. 3

69--81

EN

The automotive, aerospace and marine industries make extensive use of aluminum and its alloys to produce a wide variety of components. This prompts research work related to improving manufacturing processes using these materials. One of the main problems in this area is the durability of cutting tools. This article describes the results of tests on wear of the coated and uncoated carbide cutting tools during turning of EN AW 2007 aluminum alloy. The tests were carried out under dry conditions and at higher cutting speeds. On the face rake, the VBB indicator (average width of the flank wear) and on the rake face, the KB indicator (crater width on the rake face) were evaluated. Only for the uncoated insert, the break-in period, steady-state wear region and intensive wear were observed and the limited alue of the VBB indicator was obtained after 36 minutes of the tool life. The TiAlN+TiN coated insert, as well as TiCN achieved very short tool life periods of 16 and 24 minutes, respectively. Compared to the uncoated and the TiCN coated insert, a VBB increase of about 170% was obtained for the TiAlN+TiN coated insert after 16 minutes. In contrast, an increase in the VBB of almost 60% was obtained for the TiCN coated insert after 24 minutes, compared to the uncoated insert. Compared to the uncoated insert, an increase of 12.1% in the KB value was obtained for the TiCN coated insert, and 18.2% for the TiAlN+TiN coated insert. The main wear mechanism of the tested cutting inserts was the phenomenon of adhesion. Abrasion wear is observed on the surfaces of the TiAlN+TiN and TiCN coated inserts. The TiCN coated insert also showed coating delamination. The build-up edge (BUE) phenomenon is observed on the surfaces of the TiAlN+TiN coated and uncoated inserts.

7

Improvement Friction Welded 6063 – T6 Aluminum Alloy Joint Properties

Al Bhadle Basim M. A., Hassoni Safaa M., Hassan Kharia Salman

International Journal of Applied Mechanics and Engineering

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2024

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Vol. 29, no. 4

24--32

EN

This study aims to investigate the effect of shot peening on the mechanical characteristics and microstructure of an aluminum alloy 6063 friction welded joints. 6063 bars with 12mm diameters and 70mm lengths were prepared; some of them were shot peened by steel balls (diameters 1.25 mm) for 15 minutes before the friction welding was carried out on a traditional lathe machine at 1200 rpm. X-ray radiography was used to identify the various internal defects like porosity, concavities, and cracks. The quality of each welded joint was evaluated by hardness test, microstructure analysis, X-ray diffraction, tensile test, and bending test. It was discovered that the fine grain structure of the aluminum alloy weld connection matrix results in a strong and reliable shot peening, contributing to improving the tensile and bending strength of weld joints with a percentage of 63.6% and 12.5 %, respectively.

8

Quality Control of Liquid Aluminium Alloy Using Thermal Imaging Camera

Władysiak Ryszard

Archives of Foundry Engineering

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2024

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Vol. 24, iss. 1

135--140

EN

This paper presents the results of a study on the use of infrared thermography to assess the quality of liquid metal, a basic semi-finished product used in foundry production. EN AC-46000 alloy with the designation AlSi9Cu3(Fe) was used for the study. The crystallization process of the alloy was investigated using the TDA method with a Crystaldigraph device and Optris PI thermal imaging camera. The research describes how to use a thermal imaging camera to assess the quality of aluminium alloys. These alloys, due to their propensity in the liquid state to oxidise and absorb hydrogen, a refining procedure in the melting process. The effects of alloy refining are evaluated during technological tests of hydrogen solubility, density and casting shrinkage. The results presented in this paper showed that there is a statistical correlation between the density of the metal and the temperature values from the thermogram of the sample, obtained during its solidification. The existing correlation makes it possible to develop a thermographic inspection algorithm that allows a fast and non-contact assessment of aluminium alloy quality.

9

Properties of Casting Al-Cu Alloy Modified by Mixed Rare Earth (La, Ce) and its Mechanism Analyzed

Li Xin, Nurtilek Medetbek Ulu, Zeng Qi, Zhang Ziqi, Wang Lixia, Wu Quan, Mao Peixuan, Li Rong

Archives of Foundry Engineering

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2024

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Vol. 24, iss. 2

69--87

EN

To improve the mechanical properties of casting aluminum-copper alloy, the mixed rare earth (RE) was added to ZL206 and its properties and the enhanced mechanism of alloy were researched. The results showed that the strength and hardness of the composite were improved by 10.2% and 6.2%, respectively. After adding mixed RE, which was led by the heterogeneous enrichment area blocking the growth of the α-Al phase and making grain refinement during the solidification process. The simulation results of RE surface adsorption models by first principles also showed that the elastic constant calculation improved the bulk modulus, shear modulus, and Young's modulus of the material. The addition of mixed RE enhances the strength and hardness, although it adversely affects toughness and reduces the machining index. Also, the work function decreased, and the Fermi level increased, reflecting that the electron locality on each band was strong and the bonding state of the alloy system was covalent, which showed that the corrosion resistance was enhanced after adding mixed RE. It provides a new method for the mechanism of RE-modified aluminum-copper alloys and expands the direction of cast aluminum-copper alloy modification.

10

Investigation of The Effect of Mechanical Vibration Applied During Solidification on The Microstructure and Properties of Aluminum 356 Alloy

Özgü Taha Süreyya, Çalın Recept, Tanış Naci Arda

Archives of Foundry Engineering

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2024

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Vol. 24, iss. 1

26--31

EN

Manufacturing by casting method in aluminum and its alloys is preferred by different industries today. It may be necessary to improve the mechanical properties of the materials according to different industries and different strength requirements. The mechanical properties of metal alloys are directly related to the microstructure grain sizes. Therefore, many grain reduction methods are used during production or heat treatment. In this study, A356 alloys were molded into molds at 750°C and exposed to vibration frequency at 0,8.33, 16.66, 25, and 33.33 Hz during solidification. Optical microscopes images were analyzed in image analysis programs to measure the grain sizes of the samples that solidified after solidification. In addition, microhardness tests of samples were carried out to examine the effect of vibration and grain reduction on mechanical behavior. In the analyzes made, it was determined that the grain sizes decreased from 54.984 to 26.958 μm and the hardness values increased from 60.48 to 126.94 HV with increasing vibration frequency.

11

Wear resistance of hard anodic coatings fabricated on 5005 and 6061 aluminum alloys

Kwolek Przemysław, Obłój Andrzej, Kościelniak Barbara, Buszta Regina, Tokarski Tomasz, Krupa Krzysztof, Gradzik Andrzej, Nowak Wojciech J., Wojnicki Marek, Motyka Maciej

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 2

art. no. e51, 2024

EN

The wear resistance of hard anodic coatings fabricated on 5005 and 6061 aluminum alloys was determined. The Taber abrasion test, ball-on-disc tribological test, and scratch test at constant load were conducted. The wear resistance of the hard coating fabricated on the 6061 alloy was found to be higher compared to the coating on the 5005 alloy. This is related to the lower nanoscale porosity of the former, and the higher hardness of the 6061 alloy compared to 5005. The specific wear rates for the load of 4.905 N were equal to 1.70 × 10−5 and 1.02 × 10−5 mm3 N−1 m−1 for the coatings on 5005 alloy and 6061 alloy, respectively. In the case of the hard anodized 5005 alloy, the specific wear rate increased with increasing load to 4.56 × 10−5 mm3 N−1 m−1 whereas for anodized 6061 alloy to 1.98 × 10−5 mm3 N−1 m−1. It was also found that the protective properties of the coating on 6061 alloy do not change significantly across the coating thickness.

12

Influence of temperature and number of passes during twist channel angular pressing (TCAP) on the microstructural, mechanical, and corrosion properties of Mg-4Li-Ca

Bednarczyk Iwona, Dobkowska Anna, Hilšer Ondřej, Rusz Stanislav, Pastrňák Martin, Čada Radek, Jabłońska Magdalena, Tkocz Marek, Kowalczyk Karolina, Palgan Daria, Necas David, Mizera Jarosław

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 2

art. no. e89, 2024

EN

In this study, the possibilities of improving the mechanical and corrosion properties of Mg-4Li-1Ca processed using twist channel angular pressing (TCAP) were investigated. There was a special focus on the optimization of the TCAP parameters through analyzing how the temperature of TCAP influences the microstructural, mechanical, and corrosion properties of the alloy, and how an increasing number of TCAP passes affects these properties. It was shown that among specimens extruded with one pass, the highest mechanical properties were achieved at 180 °C. Microstructural changes were noted at higher temperatures and caused a decline in the mechanical properties. The influence of an increasing number of passes through the TCAP channel was rather minor and did not lead to significant microstructural strengthening. In contrast, the best corrosion performance was observed after four passes at 180 °C and after a single pass at 300 °C. The results of this study show that TCAP is an efficient method for the grain refinement of hcp-structured metals, lowering the costs of the plastic deformation of Mg-based alloys.

13

Influence of copper content on the structure and properties of aluminium alloys

Płonka Bartłomiej, Żyłka Konrad, Remsak Krzysztof, Rajda Marek, Zdunek Joanna, Moszczyńska Dorota

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 1

art. no. e8, 2024

EN

Designing new aluminium alloys always requires an assessment of the influence of modified contents of the main alloying additions on the required properties for a specific application. The aim of this study was to develop a new alloy with a higher tensile strength than the tensile strength obtained in typical 6xxx series alloys, with a satisfactory hot extrusion ductility. The article presents the results of studies on the influence of copper additions, in three variants, on the structure and mechanical properties of extruded aluminium profiles in various heat treatment states. The base reference for the presented studies was the following aluminium alloys: AlMgSi (EN AW-6063) and AlCuMgMn (EN AW-2017). On this basis, three alloy variants with Cu contents of 2.5, 3.5 and 4.5 weight % were selected. These alloys were cast by vertical semi-continuous casting in the form of ingots with a diameter of 100 mm. Hot deformation studies were carried out in the process of co-extrusion on a semi-industrial line consisting of a horizontal 5 MN press together with auxiliary devices. The extruded profiles were free from defects that could have resulted from the process, such as overheating, cracks and blisters. The materials in the form of extruded profiles, in the heat treatment states T1 and T4, were characterised in terms of structure and mechanical properties. The variants with Cu contents of 2.5 wt% and 3.5 wt% had comparable structure and grain size, and the variant with 4.5 wt% Cu had a finer microstructure. For the studied alloys after heat treatment, higher the strength, higher the Cu content in the alloy, ranging from 445 to 543 MPa. It has been found that it is possible to develop modified aluminium alloys based on the 6xxx series with an increased copper addition (but still below the content typical for Al alloys of the 2xxx series) that will have a strength above 400 MPa. The first variant of the new alloy with a Cu content of 2.5 wt% meets the set goal and meets the requirements set at the beginning of the studies.

14

The effect of varnishing and soaking on formability of the AW-5052-H28 aluminium alloy sheets in Erichsen cupping test

Żaba Krzysztof, Kuczek Łukasz, Balcerzak Maciej

Advances in Mechanical and Materials Engineering

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2024

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Vol. 41, nr 1

137--144

EN

This article presents the results of experimental tests on the stretch-forming ability of 0.21-mm-thick AW-5052-H28 aluminium alloy sheets used in the production of pull-off cups. Erichsen test under various tribological conditions (dry friction, lubrication with graphite lubricant) was used to assess the sheet formability. Punches with a various diameter of the spherical end (8 and 20 mm) were used in the tests. The effect of soaking conditions and varnishing variants on the value of Erichsen indices IE and IE11 was investigated. The sheets were soaked for 13 minutes at various temperatures: 185°C, 190°C and 200°C. In test conditions without lubrication, the lowest value of the IE index = 3.3 mm was observed for sheets in as-received state and for samples after soaking. However, the highest values of the Erichsen index in tests without lubrication were measured for varnished samples and repeatedly soaked. The tests conducted under lubrication conditions with graphite grease revealed usually higher values of the IE index compared to testing conditions without the use of grease. The values of the IE11 index were approximately twice lower than the IE indices. Observation of the bulge surface revealed a smooth surface, which means that the material is characterised by a fine-grained microstructure.

PL

W tym artykule przedstawiono wyniki badań eksperymentalnych odkształcalności blach ze stopu aluminium AW-5052-H28 o grubości 0.21 mm stosowanych do produkcji kapsli zawierających zawleczkę. Tłoczność blachy określono metodą Erichsena w warunkach tarcia suchego i smarowania smarem grafitowym. Wykorzystano stemple o średnicy sferycznej końcówki 8 oraz 20 mm. Badano wpływ warunków lakierowania i wygrzewania na wartość wskaźników Erichsena IE oraz IE11. Wygrzewanie blach przeprowadzano w czasie 13 minut i w różnej temperaturze: 185°C, 190°C oraz 200°C. W warunkach bez smarowania najmniejszą wartością wskaźnika IE = 3,3 mm charakteryzowały się blachy w stanie dostawy oraz próbki po wygrzewaniu. Natomiast najwyższe wartości wskaźnika Erichsena w badaniach bez smarowania zmierzono dla próbek lakierowanych oraz wielokrotnie wygrzewanych. Testy przeprowadzone w warunkach smarowania smarem grafitowym ujawniły przeważnie większe wartości wskaźnika IE w porównaniu do warunków testowania bez użycia smaru. Wartości wskaźnika IE11były około dwukrotnie mniejsze niż wskaźnika IE. Obserwacja powierzchni wytłoczenia pozwoliła stwierdzić gładką powierzchnię, co oznacza, że materiał charakteryzował się drobnoziarnistą mikrostrukturą.

15

Hardness, corrosion behavior, and microstructure of Al-Cu-Mg alloy as a function of 0.3 wt.% Zr addition

Saad Karrar, Al-Murshdy Jassim M. Salman

Diagnostyka

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2023

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Vol. 24, No. 1

art. no. 2023104

EN

The effect of adding zirconium (Zr) as an alloying element to Al-Cu-Mg alloy on the hardness and corrosion of this alloy was investigated. The hardness and polarization test results of samples treated for various periods by aging at 423.15 K for 3hr showed a significant increment in the Brinell hardness (HBW) improvement ratio of 115.6% (from 45HBW to 97HBW) and an extreme reduction the corrosion rate of the alloy after Zr adding decrease in the current density by 79.42% (from 56.50 µA cm-2 to 11.63 µA cm-2) with aging for 3 hr compared to the base alloy. The impact of this addition is also reflected in the strengthening, recrystallization, and modification of the grain microstructure. These changes were clearly demonstrated by microscopic testing and proves that the addition of Zr has a considerable synergistic effect causing inhibition of recrystallization and refinement of grain size.

16

Influence of plunger motion profile of high pressure die casting on the casting porosity and solidification rate

Żak Katarzyna, Dańko Rafał, Żak Paweł L., Kowalczyk Wojciech

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 5

art. no. e147339

EN

The high pressure die casting (HPDC) is a technique that allows us to produce parts for various sectors of industry. It has a great application in such sectors as automotive, energy, medicine, as the HPDC allows us to produce parts very fast and very cheaply. The HPDC casting quality depends on many parameters. The parameters among others, are cast alloy alloy metallurgy, filling system design, casting technology elements geometry and orientation, as well as, machine operation settings. In the article, different plunger motion schemes of the HPDC machine were taken into account. Analyses lead to learning about plunger motion influence on the casting porosity and solidification process run. Numerical experiments were run with the use of MAGMASoft® simulation software. Experiments were performed for industrial casting of water pump for automotive. Main parameter taken into account was maximal velocity of the plunger in the second phase. The analysis covered porosity distribution, feeding time through the gate, temperature field during whole process, solidification time. Cooling curves of the casting in chosen points were also analysed. Obtained results allow us to formulate conclusions that connect plunger motion scheme, gate solidification time and the casting wall thickness on the solidification rate and porosity of the casting.

17

Evaluation of the Effect of External Conditions During Crystallization and Solidification on the Final Structure of AlSi7Mg

Radkovský Filip, Gawronová Martina, Kroupová Ivana

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 1

118--123

EN

Abstract The paper deals with the possibilities of influencing the final microstructure of aluminium alloy castings by changing the external conditions of crystallization and solidification. Aluminum alloys, especially Al-Si alloys, are nowadays one of the most used non-ferrous metal alloys, especially due to their mass application in the automotive field. It is in this industry that extreme emphasis is placed on the quality of cast parts with regard to safety. For this reason, a key production parameter is the mastery of the control of the resulting microstructure of the castings and the associated internal quality, which is subject to high demands defined by international standards. The aim of the experiment of this paper is to evaluate the effect of different preheating of the metal mould on the resulting structure and hardness of test castings made of AlSi7Mg0.3 material. The hardness measurement will be evaluated on a hardness tester. The parameter SDAS, Microporosity, Content of excluded eutectic will be evaluated. Dependencies will be found and plotted.

18

The effect of pulsed electric current on the structural and mechanical behavior of 6016 aluminium alloy in different states of hardening

Dobras Daniel, Zimniak Zbigniew, Zwierzchowski Maciej

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 3

art. no. e166, 2023

EN

This study presents the effect of high current pulses on the structural and mechanical behavior of the 6016 aluminium alloy in three different states of hardening: naturally aged, super saturated, and annealed. The 6016 aluminium alloy was used for the first time in terms of electrically-assisted forming. The influence of the application of different current parameters on the material behavior was conducted. The study of electrically-assisted tensile tests showed that the application of current pulses results in a distinct response of the material, depending on the hardening state. Although in a hardened state, the mechanical properties and plasticity are deteriorated, in the solution treated state, they are improved. For the changes of the material properties is responsible the interaction of the flowing current with the precipitates and the aging process. The new parameters were proposed to describe the distinctions in the material properties between the different states of hardening of the aluminium alloy during the electrically-assisted tension. The material examination was conducted using light and scanning electron microscopy, using also electron backscattered diffraction methods. The application of, for example, the grain orientation spread parameter demonstrated the presence of recrystallized grains, in electrically-assisted specimens.

19

Material flow law and mechanical property of 5052 aluminum alloy sheets under dynamic and quasi-static hole-flanging

Zhang Lei, Cui Xiaohui, Yan Ziqin, Yang Guang

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 3

art. no. e203, 2023

EN

The formability of aluminum alloys at room temperature is low, which can lead to the fracture of the sheets under traditional stamping. In this work, electromagnetic forming (EMF) and stamping flanging of 5052 aluminum alloy sheets were performed by experimentally and 3D numerical simulation. Under stamping flanging, when the prefabricated hole diameter decreases, the flanging height increases, but the gap between the flanged part and die and maximum thinning rate becomes larger. With the increase of discharge voltage, the fittability of the flanged parts is improved. There is a critical discharge voltage, under which the fittability and maximum thinning rate are optimal. Compared with stamping, the sheet flanging height is larger under EMF. This is due to the inner and outer layers of sheet fillet are subjected to greater radial tensile strain, and the thickness of sheet fillet are reduced after EMF. In addition, the sheet mouth collides with die at high speed, which causes the mouth material extend radially. The results revealed that the hardness of outer and middle layers at the sheet fillet was larger after EMF than that after stamping, while that of the inner layer was relatively small. This distribution of hardness corresponds to material strain.

20

Effect of the lubrication on the friction characteristics of EN AW-2024-T3 aluminium alloy sheets

Krasowski Bogdan, Kubit Andrzej

Zeszyty Naukowe Politechniki Rzeszowskiej. Mechanika

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2022

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z. 94

23--35

EN

The article presents the results of friction tests conducted on EN AW-2024 Alclad aluminium alloy sheets. The lubrication efficiency of oleic acid, mineral and vegetable oils with the addition of SiO2 and TiO2 nanoparticles was determined using the strip drawing test to assess the friction conditions in the flange area in the deep drawing process. The samples in the form of sheet metal strips were pulled between countersamples with a rounded surface at a speed of 2.5 mm/s. Gear oil and oleic acid demonstrated the lowest value of the coefficient of friction (COF) in the whole range of nominal pressures investigated. The lowest efficiency in reducing the COF was shown by hydraulic oil, olive oil and machine oil. A high content of TiO2 nanoparticles (0.5-0.9%wt%) is beneficial in the friction process involving oleic acid.

PL

W artykule przedstawiono wyniki badań tarcia blach ze stopu aluminium EN AW-2024-T3 Alclad. Efektywność smarowania za pomocą kwasu oleinowego, olejów mineralnych oraz roślinnych z dodatkami nanocząstek SiO2 oraz TiO2 została określona za pomocą testu przeciągania blachy używanego do oceny warunków tarcia panujących w kołnierzowej części wytłoczki w procesie głębokiego wytłaczania. Próbki w postaci pasów blachy przeciągano pomiędzy przeciwpróbkami o zaokrąglonej powierzchni (R = 200 mm) z prędkością 2,5 mm/s. Olej przekładniowy oraz kwas oleinowy zapewniły najmniejszą wartość współczynnika tarcia w całym zakresie analizowanych nacisków nominalnych. Najmniejszą efektywność zmniejszania współczynnika tarcia wykazały olej hydrauliczny, oliwa z oliwek oraz olej maszynowy. Najkorzystniejszy efekt zmniejszenia wartości współczynnika tarcia wynikający z dodatku nanocząstek SiO2 jest widoczny dla kwasu oleinowego przy zawartości nanocząstek 0,5% (wagowo). Wysoka zawartość nanocząstek TiO2 (0,5-0,9% wagowo) jest korzystna podczas procesu tarcia z udziałem kwasu oleinowego.