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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

Manufacturing errors analysis of welded aluminum structures

Kubicki Krzysztof

Materiały Budowlane

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2025

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nr 10

208--213

EN

Welding of aluminum alloy elements is more demanding than those made of steel. This causes a greater number of welding imperfections and defects. The aim of the work was to identify the causes of manufacturing errors in welded aluminum structures. Based on example joints with welding imperfections, an analysis of the causes of these errors was presented. Manufacturing recommendations for welds in aluminum alloy structures were given.

PL

Spawanie elementów ze stopów aluminium jest bardziej wymagające niż wykonanych ze stali. Powoduje to powstawanie większej liczby niezgodności i wad spawalniczych. Celem pracy prezentowanej w artykule była identyfikacja przyczyn powstawania błędów wykonawczych spawanych konstrukcji aluminiowych. Na podstawie przykładowych połączeń z niezgodnościami spawalniczymi przedstawiono analizę przyczyn powstawania tych błędów. Podano zalecenia wykonawcze dotyczące spoin konstrukcji ze stopów aluminium.

3

Strain-controlled uniaxial fatigue of an AA2519 aluminium alloy sheet

Pejkowski Łukasz, Kotyk Maciej

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2025

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Vol. 73, nr 4

art. no. e154271

EN

This study provides a comprehensive investigation of the uniaxial, strain-controlled fatigue behaviour of an AA2519 aluminium-copper alloy. The alloy was characterized in the as-fabricated state. Three orientations relative to the rolling direction were used to determine the mechanical properties. The quasi-static strength and cyclic stress-strain response of the AA2519 aluminium alloy for the examined cases were similar regardless of the rolling direction, although slight differences between them were noticeable. Similarly, the fatigue life was not strongly affected by the specimen orientation. The investigation also included fractographic analysis of the fracture surfaces, revealing differences between strain amplitude levels and specimen orientations. The experimental results obtained provide a good basis for engineering applications of the analyzed AA2519 alloy and offer a solid foundation for further research into the effect of heat treatment on the fatigue strength of the investigated alloy.

4

Analysis of the Deflection of Aluminum Profiles for Special Applications Using FEM

Bajor Teresa, Kułakowska A., Szkudelski S.

Archives of Foundry Engineering

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2025

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Vol. 25, iss. 1

5--10

EN

The study presents a numerical analysis and experimental verification of deflection of the elements of the band that forms the superstructure of a medium-sized fire-fighting and rescue vehicle. The conducted tests were aimed at the selection of the FEM numerical model enabling the identification of the strain of the structure and the determination of the state of deformation under operational loads. The numerical tool used for the analysis was the Ansys software. Based on the conducted tests, it was possible to identify the key areas of the band in which the occurrence of the highest loads is predicted. The use of a numerical solution allows for determining the safe performance level of the designed element before putting it into production. It allows, among other things, to estimate the maximum deflection of a cross-section of a given length loaded perpendicularly and parallel to the direction of extrusion. The cases analyzed in the work are important from the point of view of their application in the construction of a medium rescue and firefighting vehicle.

5

Microstructure and strengthening mechanism of a 316 stainless steel coating prepared by high-speed laser cladding on an aluminum alloy plate

Zhang Hengyuan, Cheng Wangjun, Yin Yuandong, Sun Yaoning, Li Xiao

Archives of Civil and Mechanical Engineering

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2025

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Vol. 25, no. 1

art. no. e15, 2025

EN

Aluminum alloy plates show great potential in energy storage and transportation applications. Nevertheless, the low surface strength of aluminum alloy plates negatively impacts their performance and safety. Aluminum alloys exhibit characteristics such as a low melting point, high reflectivity, and a rapid dilution rate, posing significant challenges for laser cladding coatings. This paper presented the surface modification mechanism of aluminum alloy plates. A stainless steel coating was successfully prepared on the surface of aluminum alloy substrates by using high-speed laser cladding technology. The microstructure, microscopic morphology, and microhardness of the coatings were conducted. The surface and sides of coatings were analyzed by XRD, SEM, EBSD, and microhardness testing, respectively. It is found that larger cellular crystals and carbides predominate at the junction of the substrate and the coating. The middle part of the 0.5-mm coating from the connection and the heat-affected zone are mainly dendritic crystals. The top of the 1-mm coating from the connection is mainly fine crystals. This means that local grain refinement occurs in the stainless steel coating via high-speed laser cladding. There is a transformation of FCC to BCC in the coating. Moreover, the cross-section of the coating exhibits a relatively high microhardness, ranging from 517 to 679 HV. The microhardness at the substrate is measured at 67 HV. The maximum microhardness of the coating is ten times that of the substrate. The bottom of the coating maintains a relatively high microhardness due to the presence of a large amount of carbides. The microhardness of the coating gradually increases from the middle to the surface of the coating. This is primarily attributed to solid solution strengthening and fine grain strengthening mechanisms. Columnar crystals at the metallurgical bond between the substrate and the coating transform into fine grains at the top, leading to a gradual refinement of the microstructure. High-speed laser cladding technology facilitates the enhancement of surface properties and the improvement of surface strength in traditional aluminum alloys.

6

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.

7

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.

8

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.

9

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.

10

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.

11

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.

12

Effect of the chemical composition of aluminium alloy EN AW-2024 on the strengthening state after T6 and T6I6 treatment

Staszczyk A., Lipa S., Adamczyk-Cieślak B., Sawicki J.

Archives of Materials Science and Engineering

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2024

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Vol. 129, nr 1

5--16

EN

Purpose: The work focuses on comparing three EN AW-2024 aluminium alloys with different chemical compositions within the standard limits to understand the influence of the chemical composition on the mechanical properties obtained. The study discusses the correlations between intermittent ageing processes and the improved strength, hardness, and fatigue resistance of some alloys compared to traditional aging processes. Design/methodology/approach: To understand how the chemical composition affects the mechanical properties, each alloy underwent T6I6 treatment (intermittent ageing with a weekly break) compared to traditional T6 treatment. The study involved SEM and TEM microscopic observations, as well as EDS tests to analyse the chemical composition, hardness, and uniaxial tensile testing. Findings: In the research conducted, both SEM and TEM microscopic observations revealed a similar percentage of intermetallic phase particles in the alloys. However, there were significant differences in the size and distribution of the particles. The alloy with the maximum Fe and Si content showed the highest particle refinement. Despite the observed differences in microstructure, the tests for Young's modulus, yield strength, and strength were found to be the same or very similar and were not influenced by the alloy processing process. The only notable difference in the strength parameters was the parameter marked as elongation in the direction of tension, with its lowest value observed in the alloy with the highest Si content. Research limitations/implications: The issue that arose during the analysis is accurately evaluating the alloy's morphology, particularly defining the three-dimensionality of the resulting phases using TEM. To conduct a more comprehensive analysis, additional tests need to be performed for statistical significance. In the future, SEM and TEM analyses and real-time tensile tests on specially prepared samples under the microscope would be beneficial. Practical implications: The work presented addresses whether the chemical composition of the standard area plays a crucial role in achieving consistent mechanical properties of the aluminium alloy after the ageing processes. Despite the observed structural differences, the material's mechanical properties remained unchanged. This information is valuable for process design. Originality/value: Comparison of mechanical properties, morphology, and phases formed after the ageing process of alloys of the same grade with minor differences in chemical composition.

13

Research into the Structure and Adhesion of WCCoCr Coatings Plasma-Sprayed onto Castings of AlSi Alloy Plates

Radoń M., Opiekun Z., Kupiec B.

Archives of Foundry Engineering

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2024

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Vol. 24, iss. 3

76--80

EN

The article presents structural investigations and mechanical properties of hard coatings deposited by spraying WCCoCr powder in an argon hydrogen plasma jet onto the surfaces of AlSi10Mg alloy casting plates. Two variants (A and B) of processing parameters of the powder spraying process onto the surface of silumin plates were applied, resulting in different coating thickness. The coating applied according to variant A was done with 12 passes, and its thickness was approximately 150 µm. The coating applied according to variant B was done with 20 passes, and its thickness was about 320 µm. The microstructures of these coatings are similar, consisting of wavy, alternately deposited phases of solid solutions with varying concentrations of elements, and fine spherical phases, irregularly dispersed carbides. A qualitative analysis of the distribution of microstructure components was performed based on surface mapping. Precipitates differing in their degree of grayness and shape were identified based on microanalysis of their chemical composition. The porosity assessment of coatings performed in five randomly selected areas amounts to an average of 9%. The applied coatings exhibit good adhesion to the substrate, as evidenced by the absence of delamination during scratching tests using a diamond Rockwell indenter loaded with a force of 10 N. The coating hardness averaged 1180HV0.2. The test results indicate the high quality of the WCCoCr coatings, regardless of their thickness.

14

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.

15

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.

16

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.

17

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.

18

Understanding the microstructural evolution and fatigue behavior of aluminum 2319 fabricated by wire arc additive manufacturing

Kannan A. Rajesh, Pramod R., Prakash K. Sanjeevi, Shanmugam N. Siva, Yoon Jonghun, Oliveira J. P.

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 2

art. no. e110, 2024

EN

Aluminum alloys have received substantial interest for the fabrication of complex and large size components for the aerospace industry via additive manufacturing processes. This work explores the fatigue performance of aluminum alloy 2319 fabricated by wire-based Directed Energy Deposition (DED) with Cold Metal Transfer (CMT) process, i.e., wire arc additive manufacturing (WAAM) technology. The as-deposited 2319 wall microstructure was composed by both columnar dendrites and equiaxed grains along the build direction (BD). Also, fine and coarse θ and θ′ precipitates were noticed in the WAAM printed 2319 wall due to repeated thermal cycles while fine precipitates were observed in wrought alloy. The microhardness measurements revealed a gradual decrease from the bottom to the top layers and varied between 65 and 86 HV. Tensile properties (yield strength, ultimate tensile strength, and elongation) measured in the horizontal and vertical directions were 99 ± 4 MPa, 268 ± 11 MPa 14.8 ± 1.5% and 96 ± 3 MPa, 257 ± 9 MPa, and 15.6 ± 2%, respectively. The WAAM 2319 fabricated in this work retained 72% of the strength of their AA2219-T62 wrought counterparts, which can be attributed to the large columnar grains that developed during the additive manufacturing process. The fatigue strength of WAAM 2319 specimen was 67 MPa, corresponding to 65% of the fatigue strength of AA2219-T62. Fracture surface analysis revealed the presence of small and large dimples, secondary micro-cracks, broken intermetallics, and inclusions. This work will provide novel insights and guidance for manufacturing near-net shape aluminum alloys by wire-based DED with improved tensile and fatigue properties.

19

Mechanical and tribological properties of Ti1-xZrxB2 coatings deposited by magnetron sputtering on hot work steel

Cieniek Łukasz, Kopia Agnieszka, Kot Marcin, Cempura Grzegorz, Gruszczyński Adam, Kopyściański Mateusz, Smolik Jerzy, Kacprzyńska-Gołacka Joanna

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 3

art. no. e166, 2024

EN

Low fracture toughness is a common problem encountered by many researchers in the application of pure TiB2 coatings. To improve their properties, a convenient and useful method is the use of doping, so this study proposes the deposition of TiB2 enriched with Zr on a steel substrate. The objective of the research was to investigate the impact of Zr addition to TiB2 coatings on both their mechanical and tribological properties. Four coatings with varying compositions (pure TiB2; TiB2 doped with 3, 6, and 10 at.% Zr) were deposited using magnetron sputtering from TiB2 and Zr targets. The coating structures were analyzed by means of X-ray diffraction (XRD), transmission electron microscopy (TEM), and atomic force microscopy (AFM). Nanoindentation, scratch test, and ball-on-disk test were used to determine the mechanical and tribological properties. In most cases, only two factors have a significant impact on the mechanical and tribological properties of the Zr-doped coating. Firstly, a change in the preferred orientation of the coating from (102)(111) to (100) results in increased hardness and wear resistance. Secondly, a reduction in crystallite and column size enhances ductility and fracture toughness by impeding or altering the direction of crack propagation. Based on the study, one can conclude that the optimal Ti1-xZrxB2 properties were obtained for 6 at.% Zr content.

20

Latest advances in extrusion processes of light metals

Leśniak Dariusz, Zasadziński Józef, Libura Wojciech, Gronostajski Zbigniew, Śliwa Romana, Leszczyńska-Madej Beata, Kaszuba Marcin, Woźnicki Antoni, Płonka Bartłomiej, Widomski Paweł, Madura Jacek

Archives of Civil and Mechanical Engineering

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2024

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Vol. 24, no. 3

art. no. e184, 2024

EN

The paper presents a review of the literature and authors’ research on the current achievements in the field of extrusion of aluminium alloys, magnesium alloys, powders and aluminium-based composites in particular. The microstructure transformations taking place during homogenisation of billets from the medium- and high-strength heat-treatable aluminium alloys are still an object of interest of researchers. The recently published papers are related to dissolution of soluble phases formed during solidification and elimination of microsegregation, precipitation of the dispersoids, insoluble phases’ transformation as well as particles re-precipitation during cooling. The novelties in the extrusion of magnesium alloys and aluminium-based composites are shortly reported. Specifics of the extrusion dies design and their working conditions, which limit the products quality and working life of the tools, are extensively reported. The computer-aided designing (CAD) and finite-element method (FEM) and 3D optical scanning were used in analysis aimed at dimensional deviations of the dies and the extruded products. The surface engineering techniques such as welding techniques, diffusion layers and protective coatings such as produced by physical vapour deposition (PVD), plasma-enhanced physical vapour deposition (PAPVD), chemical vapour deposition (CVD) and plasma-enhanced chemical vapour deposition (PECVD) are described. Various original methods of extrusion including the severe plastic deformation processes (SPD), such as cyclic extrusion compression (CEC), equal-channel angular pressing (ECAP) and hydrostatic extrusion (HE) are discussed. The above techniques as well as the new KOBO extrusion process with oscillating die movement generate significant refining of the microstructure of metals and alloys and enable consolidation of the powdered materials. The application of the rapid solidification process connected with the hot extrusion permits production of beneficial microstructure and above-standard mechanical properties of the extruded products. Finally, the opportunities and directions of development of the extrusion process of metals and alloys are indicated.