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1

Wpływ zawartości grafitu na właściwości mechaniczne warstw hybrydowych Ni-P/Si3N4/grafit osadzonych na stopie AW-7075 metodą redukcji chemicznej

Czapczyk Kazimierz

Przemysł Chemiczny

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2024

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T. 103, nr 1

86--92

PL

Przedstawiono wpływ obecności grafitu jako fazy dyspersyjnej na właściwości mechaniczne warstw hybrydowych Ni-P/Si₃N₄/grafit, które osadzono metodą redukcji chemicznej na stopie glinu AW-7075. Wykonano badania morfologii powierzchni warstw metodą mikroskopii świetlnej i skaningowej. Dalszą część pracy stanowiły badania mechaniczne, czyli pomiary mikrotwardości warstw oraz ich adhezji do aluminiowego podłoża, a także analizy wpływu obecności grafitu na podstawowe właściwości materiału powłokowego. Zbadano próbki ze stopu AW-7075, na których osadzono metodą bezprądową powłoki hybrydowe i porównawczo nanokompozytowe o różnym składzie chemicznym, modyfikowanym zawartością faz dyspersyjnych.

EN

The mech. and adhesive properties of Ni-P/Si₃N₄ and Ni-P/Si₃N₄/graphite coatings deposited using the electroless method on the AW-7075 Al alloy were compared. Coatings with different chem. compns., modified by the content of dispersion phases (Si₃N₄ and graphite), were used. Microhardness and adhesion of the layers to the Al substrate were measured. The impact of the presence of graphite on the basic properties of the coating material was analyzed. The surface morphol. of the layers was examined using light microscopy and SEM. The incorporation of Si₃N₄ and graphite into the coating material resulted in a several-fold increase in the microhardness of the surface layer compared to the Al alloy.

2

Mechanical behaviour and failure mechanism of resistance spot welded aluminium and copper joint used in the lightweight structures

Fakhri Marwah Sabah, Al-Mukhtar Ahmed, Mahmood Ibtihal A.

Diagnostyka

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2024

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Vol. 25, No. 2

art. no. 2024207

EN

Recently, dissimilar metals have found applications in the process of resistance spot welding (RSW), particularly within the electric vehicle industry. Notably, copper and aluminum have gained significant importance in these sectors due to their advantageous characteristics for the industry requirements. The mechanical behavior of these materials is essential to maintaining structural integrity. The study aims to estimate the mechanical behavior of dissimilar RSW joints and optimize welding parameters for Cu-Al joints. Hence, understanding the joining processes in the electric vehicle industry to design reliable components. Combining different types of materials, such as T2-grade commercially pure copper sheets and aluminum AA1050 with the same thickness of 1 mm has been welded. The determination of optimal welding conditions takes into account material thicknesses and types. Through tensile-shear testing, welding parameters that yield maximal joint strength were identified. Using Minitab 19 software, the Taguchi method helped achieve optimized welding parameters. The hardness, fracture characteristics, and weld strength have been investigated. Hardness measurements were conducted across the nugget thickness and surface, offering insights into potential failure modes. The welding process involves the transition to a liquid state for the aluminum components, resulting in the formation of intermetallic compounds. Consequently, crack initiation was observed within the aluminum segments, leading to a plug-out fracture mechanism. In contrast, copper exhibits superior strength and hardness compared to aluminum, where increased hardness correlates with heightened strength. The discrepancy in hardness, especially the lower values observed on the aluminum side, caused fractures to appear within the heat affected zone (HAZ). Subsequently, this fracture propagated until pull-out failure was realized. The study revealed that dissimilar joining of Cu and Al resulted in an ultimate tensile stress of 26 MPa, while similar joining of copper showcased a strength of 98 MPa. Additionally, the symmetric join in aluminum exhibited a strength of 93 MPa. The maximum tensile shear force is equal to 512 N at a maximum welding current of 14000 A. The pull-out failure mode occurs in the Cu-Al RSW joint. The maximum hardness was noted in the fusion zone (FZ). Relevant literature sources have supported and confirmed these outcomes.

3

The influence of carbide reinforcement on the properties of sintered aluminium alloy matrix composites

Szewczyk-Nykiel Aneta

Technical Transactions

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2023

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Vol. 120, iss. 1

art. no. e2023005

EN

Based on the commercial aluminium alloy powder blend (Alumix 431D) metal matrix composites reinforced with particles of SiC as well as TiC were produced by conventional powder metallurgy technology and the effect of the type and amounts of reinforced particles on the selected properties and microstructure of sintered composites were investigated. In particular, the densification behaviour, the wear resistance and the corrosion resistance in 3.5% NaCl solution were identified. It was stated that both the type and the weight fraction of carbide used as particulate reinforcement have a great impact on the properties of aluminium alloy matrix composites. It was shown that the introduction of titanium carbide has a more favourable effect on the properties of sintered Alumix 431D matrix composites in comparison to silicon carbide and the optimum content of TiC in composite is 4 wt. % due to the highest hardness, wear resistance (wear rate of 2.865·10 ̄ ³ mm³/m) and simultaneously the best corrosion resistance (corrosion rate of 0.005 mm/year).

4

Influence of aluminum alloys surface treatment on the durability of glued joints

Kowalik Joanna, Tworek Magdalena, Smaruj Michał

Polimery

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2023

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Vol. 68, nr 10

523--529

EN

The aim of the work was to analyze the method of preparing the aluminum surface in terms of the functional properties of glued joints with the use of one-component polyurethane adhesive. Six methods of surface treatment of EN AW-5251 aluminum alloy were tested. In addition, changes in the shear strength of adhesive joints after environmental exposure were determined. The best surface preparation processes were atmospheric plasma and anodizing.

PL

Celem pracy była analiza sposobu przygotowania powierzchni aluminium pod kątem właściwości użytkowych połączeń klejonych z zastosowaniem jednoskładnikowego kleju poliuretanowego. Zbadano sześć metod obróbki powierzchni stopu aluminium EN AW-5251. Ponadto określono zmiany wytrzymałości połączeń klejonych na ścinanie po ekspozycji środowiskowej. Najlepszym sposobem przygotowania powierzchni była plazma atmosferyczna i anodowanie.

5

Assessment of eggshell and CaCO3 reinforced recycled aluminium green metal matrix

Hasan L. M., Ali A. M.

Journal of Achievements in Materials and Manufacturing Engineering

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2023

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Vol. 118, nr 2

57--61

EN

Purpose: In this study, an environmentally friendly metal matrix was prepared, and the influence of eggshell powder and CaCO3 particles on the tensile strength and hardness of recycled aluminium were assessed. Design/methodology/approach: A matrix made of recycled aluminium was employed. Calcium carbonate and eggshells served as the study's reinforcing materials. Separately, weight percentages of 2, 4, and 8% of eggshell and calcium carbonate were used. The samples were made by sand-casting. Findings: The results showed that both eggshell and calcium carbonate positively affect the hardness, yield, and ultimate tensile strength of recycled aluminium. The hardness values were improved as the percentage of the eggshell increased. The maximum hardness was achieved at 2% calcium carbonate. Similarly, the highest improvement of yield strength was for 2% CaCO3 addition, while the highest tensile strength was obtained at 8% eggshell addition. Research limitations/implications: To get better results, it would be desirable to use finer eggshells than those utilized in this study. Practical implications: Composites made with an aluminium matrix exhibit exceptional mechanical and physical characteristics. The most challenging obstacle to overcome is the cost of metal matrix composites. Eggshells are a by-product that could be employed as a lightweight, affordable form of reinforcement. One way to get rid of this by-product, improve composite characteristics, and lower the cost of aluminium composite is to use eggshells. Originality/value: A comparative investigation was carried out to determine the effects of adding agricultural by-product eggshell, and commercial CaCO3 reinforcement material on the characteristics of recycled aluminium matrix integrated 425 µm sized eggshell and CaCO3 separately as a reinforcement material to create a metal matrix that is beneficial to the environment.

6

Separation technology of components of waste pharmaceutical blisters

Miękoś Ewa, Zieliński Marek, Sroczyński Dariusz, Fenyk Anna

Ecological Chemistry and Engineering. S

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2023

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Vol. 30, nr 3

429--442

EN

In this paper, the separation technology of components of waste pharmaceutical blisters and its adaptation to the industrial scale are described. It involved, among others, taking advantage of the phenomenon of difference in the density of the individual phases that were contained in the separation tank, i.e., the separating mixture, PVC plastics, and aluminium. As a result, the directions of movement of the separated blister components were opposite. All components of the separating mixture feature a similar surface tension (γ > 20 mN/m) which facilitates the penetration of the liquid between the blister component layers. After separation, the full-value products, i.e. polyvinyl chloride (PVC) and aluminium are obtained. The resulting products can be further processed and the entire technological process is a waste-free. PVC can be melted and processed into other products e.g. plastic components for the construction industry. Pure aluminium is a metal sought after and widely used in industry due to its low specific weight. An additional element supplementing the technology is the separation tank of our design in which the separation process of the blister components takes place. The advantage of the separation tank is that the separation process can be repeated many times with the same separating mixture until it is exhausted. Both separated blister components are directed to filtering followed by air drying without a mixing PVC plastic with aluminium.

7

Research on the post-weld explosive hardening of AA7075-T651 friction stir welded butt joints

Kosturek Robert, Lewczuk Rafał, Torzewski Janusz, Wachowski Marcin, Słabik Piotr, Maranda Andrzej

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2023

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Vol. 71, nr 4

art. no. e145685

EN

In this paper, the post-weld explosive hardening of a 5 mm AA7075-T651 plate welded via FSW was performed. To investigate the possibility of increasing FSW joint mechanical properties, the welded plate was explosively treated with four various explosive materials (ammonal, emulsion explosive, FOX-7, and PBX) in two different hardening systems. As part of the investigation, the observations of the surface and macrostructure of the treated plates were described. The obtained microhardness distribution allowed us to register the increase in hardness of the SZ up to 6%, but no increase in hardness of the LHZ was reported. In most cases, the influence of explosive treatment on the mechanical properties of the welded joint was disadvantageous as ultimate tensile strength and ductility were reduced. The only positive effect which was observed is the increase in the value of yield strength up to 27% corresponding to 77 MPa, achieved by explosive materials with detonation velocity below 3000 m/s.

8

Comparison of Tensile Properties of Nb Grain Refined A206 Alloy by Gravity and Tilt Casting

Palamutcu Nuri, Dizdar Kerem Can, Sahin Hayati, Dispinar Derya

Archives of Foundry Engineering

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2023

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Vol. 23, iss. 4

49--53

EN

Turbulent filling of a mould is one of the ways to introduce extrinsic defects into the cast part that could deteriorate many properties of any casting. The turbulence can be easily eliminated by counter gravity casting. In gravity casting, tapered downsprue, tapered runner is needed such that the mould cavity is filled counter-gravity from the bottom which is the only best way to eliminate turbulence during filling. Tilt casting method also exists which has the potential to quiescently transfer the liquid into the mould cavity. In this work, gravity and tilt casting methods were used to evaluate the tensile properties of Nb grain refined 206 alloy. Three different Nb contents were investigated: 0.025, 0.05 and 0.1 wt% ratios and it was found that 0.05 wt% revealed the highest tensile properties. On the other hand, when the intrusion of surface folded oxides was eliminated during filling, it was found that mechanical properties were increased significantly, and particularly, the toughness was increased by two folds when tilt casting was applied compared to gravity casting.

9

Deformation behavior and mechanical properties of 5052-O aluminum alloy joints formed by high-speed clinching

Huang Changqing, Ji Yanan, Cui Xiaohui, Sun Xiaoming, Wang Shu, Yang Huan

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 3

art. no. e152, 2023

EN

In this paper, the high-speed clinching named electromagnetic-driven clinching (EMDC) method was adopted and analyzed by experiment, numerical simulation and theoretical calculation. The deformation behavior and mechanical properties of 5052-O EMDC joints have been investigated. The result showed that the punch speed can reach 3 m/s, The maximum strain rate of the EMDC process can reach 6000 s−1. The EMDC process can be divided into deep drawing, interlocking, and unloading stages. The neck thickness tN changes mainly in deep drawing stage. The interlock value tU changes mainly in interlocking stage. The discharge voltage level can precisely control the formation of the joint. With the increase of the discharge voltage, the tN did not change significantly, while the tU increased and mechanical properties of the joint gradually improved. When the discharge voltage was 3.4 kV, the shear and tensile joint strength were 1571 N and 746 N, respectively. The simulation results and the theoretical calculations were in good agreement with the experimental results.

10

Plasma welding of aluminum in an oxygen-free argon atmosphere

Klett Jan, Bongartz Benedict, Wolf Thomas, Hao Chentong, Maier Hans Jürgen, Hassel Thomas

Advances in Materials Science

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2023

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Vol. 23, nr 1(75)

5--18

EN

Plasma welding is characterized by a high concentration of energy, which allows for high welding speed and leads to less distortion and residual stresses compared to conventional welding processes. Due to the local and controlled heat input, the process is suitable for sheet metal from ≈ 0.1 mm (micro plasma) up to ≈ 10 mm. In the case of aluminum and its alloys, the natural aluminum oxide layer on the metal surface limits the productivity of the plasma welding process. The electrically isolating and thermally insulating Al2O3 layer has a significantly higher melting point compared to the aluminum (Tm(Al2O3) = 2072 °C vs. Tm(Al) = 660 °C). The oxide layer hinders the formation of a stable arc and can even impede the joining formation. In order to remove the oxide layer and to produce quality welds with a DC process, it is necessary to weld with reverse polarity to use the principle of cathodic surface cleaning. However, this leads to increased electrode wear and increased penetration depth, which is not always desirable. In the study presented, the use of silane to reduce the oxygen content in the welding atmosphere as well as to remove the natural aluminum oxide layer on the metal surface was investigated. As previous studies have shown that the use of silane-doped plasma-gases is suitable for removing the superficial oxide layer on aluminum components, high-quality welded joints were expected. Quality welds with sufficient dilution were achieved using a transferred arc silane-doped helium plasma. In contrast, welding with an argon-silane mixture led to excessive pores formation. Additionally challenges to stabilize the arc process were identified and ramifications with respect to process optimization are discussed.

11

Najnowsza japońska „architektura materiałów”: szkło oraz aluminium, metal i ceramika

Kido Ewa Maria, Cywiński Zbigniew

Świat Szkła

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2022

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R. 27, nr 6

18--23, 33

12

Aluminium i metale nieżelazne w 2021 roku. Historyczne rekordy cen, zachowanie się rynku i wstępne przewidywania na 2022 rok

Grifone Massimo

Przegląd Odlewnictwa

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2022

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Vol. 72, nr 3-4

190--193

PL

Rok 2021 był rokiem wyjątkowym dla surowców, a ceny metali nieżelaznych notowanych na LME nie były wyjątkiem i wzrosły o 35%. Ceny miedzi i cyny osiągnęły najwyższy poziom w historii, podczas gdy ceny aluminium i cynku osiągnęły najwyższy poziom od 14 lat. W szczególności aluminium uzyskało drugie miejsce wśród głownych metali przemysłowych, co łatwo zrozumieć, patrząc na wydarzenia, jakie miały miejsce w Chinach, największym producencie i konsumencie aluminium.

EN

2021 was an exceptional year for raw materials, and prices of non-ferrous metals listed on the LME were no exception, gaining 35%. Copper and tin prices reached an all-time high, while aluminium and zinc prices reached their highest levels in 14 years. Aluminium in particular had the second best performance among the major industrial metals, a fact easily understood when looking at what happened in China, the largest producer and consumer of aluminium.

13

The role of the chemical composition of trivalent passivation bath for aluminum 5005A series in shaping the morphology of conversion coating and corrosion resistance

Gralak Eryk, Hoffman Adrianna, Winiarski Juliusz

Ochrona przed Korozją

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2022

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nr 6

177--181

EN

5005A series aluminum samples were passivated to obtain a conversion coating based on Cr(III) compounds. It was shown that the corrosion resistance of galvanized aluminum in a bath containing both zirconium and cobalt compounds, measured in a 0.05 M NaCl solution, slightly increased compared to the corrosion resistance of aluminum as delivered, i.e. without conversion coating. In the case of galvanic treatment of aluminum in baths containing separately cobalt or zirconium compounds, a significant increase in corrosion resistance was achieved in relation to aluminum in the delivered condition. SEM analysis showed that in the presence of the simultaneous addition of zirconium and cobalt compounds, the most developed surface was created compared to the addition of only zirconium, where bright spheroidal precipitates occur locally. EDS analysis showed the presence of : C, O, Mg, Al and Si, small amounts of Cr, Zr, F on the surface of the aluminum covered with the Cr + Zr + HF conversion coating. During measurements with the use of the linear polarization resistance (LPR) technique, the best anti-corrosion properties were demonstrated by the samples that were passivated in a Cr(III) solution with the addition of Zr compound and HF and in a Cr(III) solution with the addition of Co compound and HF.

PL

Próbki aluminium serii 5005A poddano procesowi pasywacji z wytworzeniem powłoki konwersyjnej na bazie związków Cr(III). Wykazano, że odporność korozyjna aluminium poddanego obróbce galwanicznej w kąpieli zawierającej jednocześnie związki cyrkonu i kobaltu, mierzona w 0,05 M roztworze NaCl, nieznacznie wzrosła w stosunku do odporności korozyjnej aluminium w stanie dostarczenia, tzn. bez powłoki konwersyjnej. W przypadku obróbki galwanicznej aluminium w kąpielach, które zawierały osobno związki kobaltu lub cyrkonu, uzyskano wyraźny wzrost odporności korozyjnej w stosunku do aluminium w stanie dostarczenia. Analiza SEM wykazała, że w obecności jednocześnie dodatku cyrkonu i kobaltu powstała najbardziej rozwinięta powierzchnia. W przypadku zastosowania tylko dodatku cyrkonu jasne wytrącenia sferoidalne występują lokalnie. Analiza EDS wykazała obecność C, O, Mg, Al i Si, niewielkich ilości Cr, Zr, F na powierzchni aluminium pokrytego powłoką konwersyjną Cr + Zr + HF. Podczas pomiarów techniką liniowego oporu polaryzacji (LPR) najlepsze właściwości antykorozyjne wykazały próbki poddane pasywacji w roztworze Cr(III) z dodatkiem związków Zr i HF oraz w roztworze Cr(III) z dodatkiem związków Co i HF.

14

Application of the EBSD method on explosively welded joins of Al ‒ austenitic CrNi steel bimetal

Lokaj Jan, Sahul Miroslav, Sahul Martin, Čaplovic Lubomir

Materiały Wysokoenergetyczne

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2022

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T. 14(S)

146--153

EN

Electron Backscatter Diffraction (EBSD) is a scanning electron microscope (SEM) based technique, which enables a sample’s microstructure to be analysed, visualised and quantified. The EBSD method together with associated techniques provides useful information how to interpret the obtained results. Microstructure is the internal structure of a material investigated on the microscopic scale. It is of interest because a material’s internal features (i.e. structure) influences its properties and behaviour. The EBSD method has become the primary tool for characterising microstructures in most metals, alloys, composites and ceramics. The range of applications is numerous, from rapid measurement of grain size and texture in metal sheets, welded joints etc. Many of these materials are relatively simple to analyse using EBSD, but advanced tools such as high-resolution pattern correlation approaches can be applied to improve our understanding of these materials [1]. This method has been applied to investigace the structure of Al ‒ austenitic CrNi steel. Only partial results as for the EBSD method will be given here.

PL

Detektor EBSD (dyfrakcja elektronów wstecznie rozproszonych) zainstalowany w skaningowym mikroskopie elektronowym (SEM) umożliwia analizę, wizualizację i ocenę ilościową mikrostruktury próbki. Metoda EBSD wraz z powiązanymi technikami dostarcza przydatnych informacji, umożliwiających interpretację wyników. Mikrostruktura to wewnętrzna struktura materiału badana w skali mikroskopowej. Jest ona interesująca, ponieważ wewnętrzne cechy materiału (tj. struktura) determinują jego właściwości. Metoda EBSD stała się podstawowym narzędziem do charakteryzowania mikrostruktur w większości metali, stopów, kompozytów i ceramiki. Zakres zastosowań jest szeroki, obejmujący m.in. szybki pomiaru wielkości ziarna i tekstury w blachach, złączach spawanych itp. Wiele z tych materiałów można stosunkowołatwo poddać analizie EBSD, ale zaawansowane narzędzia, takie jak metody operate o analizę obrazu, można zastosować w celu lepszego poznania struktury tych materiałów [1]. Metodę tę zastosowano do badania struktury bimetalu typu aluminium-stal austenityczna CrNi. W tym miejscu omówione jedynie częściowe wyniki analizy EBSD.

15

An Analysis of the Features of Cast Composite Materials Based on Light Alloys Reinforced by Particles

Dan Olena

Journal of Casting & Materials Engineering

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2022

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Vol. 6, no. 1

8--13

EN

Light alloys are widely used in industry and everyday life due to their high physical and mechanical properties, wear and corrosion resistance, as well as low cost. In this regard, the use of light alloys as a basis for composite materials is both justified and expedient. The potential of these materials has not been fully used to this day, despite the growing interest in metal matrix composites and extensive investigations aimed at the development of production technology and the introduction of advanced systems based on light matrices. The article presents a short review of the analysis of the main components of the technology of cast composite materials based on light alloys of aluminum and magnesium reinforced by particles. Particular attention is paid to the choice of the matrix alloy, the type, size and amount of reinforcing particles introduced into it, as well as the thermal-time and kinetic parameters of the process.

16

Analysis of the influence of the blanking clearance size to the burr development on the sheet of mild steel, brass and aluminium in blanking process

Kamarul Adnan A. A., Azinee S. N., Norsilawati N., Izzul K. A. M.

Journal of Achievements in Materials and Manufacturing Engineering

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2022

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Vol. 111, nr 1

26--32

EN

Purpose: This research aims to analyse the influence of blanking clearance size on the burr development for mild steel sheet, brass and aluminium. The main reason for this research is estimating the burr size on blank parts. It is still significant since the quality of the products is determined by evaluating the amount of allowable burr in the parts. Design/methodology/approach: For the blanking process on the 3.00 mm thick sheets, various sizes of blanking clearance for a 20 mm diameter of the die opening are employed, as is the technique for obtaining the parts. Then the height of the burr on each product was measured using a micrometre and toolmaker microscope. The height of burr for each size of blanking clearance have been recorded and compared using a graph. Comparison made to identify which measure of blanking clearance and which type of material will produce a small size of burr. Findings: For mild steel, brass, and aluminium, blanking clearance 0.15 mm produced burr heights of 0.088 mm, 0.015 mm, and 0.024 mm, and blanking clearance 0.13 mm produced bur heights of 0.192 mm, 0.055 mm, and 0.046 mm, respectively. The brass had a lower burr height than mild steel and aluminium, according to the results. More significant blanking clearance (0.15 mm) produced a smaller size of burr compared to a smaller blanking clearance (0.13 mm). Practical implications: This study focuses on burr height rather than the wear of the punch and die cutting edge; burr height can affect punch and die sharpness. It also can guide practitioners in estimating blanking clearance and the burr height of mild steel, brass and aluminium. Originality/value: This paper demonstrates that the gap between the punch and die influences the burr height. The material strength also affects the burr height, with a high tensile strength resulting in a larger burr.

17

Joining of carbon steel AISI 1006 to aluminum alloy AA6061-T6 via friction spot joining technique

Ridha Munaf Hashim, Saad Mursal Luaibi, Abdullah Isam Tareq, Barrak Osamah Sabah, Hussein Sabah Khammass, Hussein Abbas Khammas

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 4

1--12

EN

This work aims to join sheets of carbon steel to aluminum alloy AA6061. A lap joint arrangement was used with a joint lap area of dimensions *25 25 mm . The joining procedure was carried out using a rotating tool of 10 mm shoulder diameter. Three process parameters, with three levels for each parameter, were selected to investigate their effects on joints quality. The parameter’s levels for each experiment were designed using the design of the experiment method (DOE). The results indicated that the two materials were joined by a mechanical interlock at an interface line, without formation of intermetallic compounds. The shear force of the joint reached an ultimate value of .4 82kN . The shear force of the joint improved by increasing plunging depth of the tool. Samples of minimum shear force value failed by a pull-outing aluminum metal from the carbon steel specimen. Samples of higher shear force value exhibited a shear mode of fracture. Increasing the rotating speed and decreasing pre-heating increased the process temperature.

18

Influence of welding parameters of resistance spot welding on joining aluminum with copper

Sar Mohammed Helan, Ridha Munaf Hashim, Husain Imad M., Barrak Osamah Sabah, Hussein Sabah Khammass

International Journal of Applied Mechanics and Engineering

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2022

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Vol. 27, no. 2

217--225

EN

The resistance spot welding (RSW) method was used to join aluminum alloy AA 1050 and copper alloy UNS C50100 sheets. Mechanical properties of the joints were examined. The influence of welding process parameters on tensile shear force of the joints was discussed. The design of experiments (DOE) method was used to analyze the influence of welding parameters on the mechanical properties of the joints. Three RSW parameters were used: welding current, squeeze time, and welding time. The results showed that the joint shear stress increased with increasing the welding current until a value of 12000 Amp. Then the shear stress decreased. The tensile shear stress increased with increasing the welding and squeeze time. As a consequence, it can be possible to weld copper with aluminum by RSW.

19

Manufacturing and properties of al-al alloy bimetallic composites obtained from powders by hot extrusion

Wojtaszek Marek, Zyguła Krystian

Composites Theory and Practice

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2022

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R. 22, nr 4

211--218

EN

This paper presents the process of manufacturing bimetallic composites in the shell-core system. Al17Si5Fe3Cu1.1Mg0.6Zr alloy powder was used for the shell. Pure aluminum was used as the core of the composite, respectively, in the form of a cast and then rolled rod, and in the form of a semi finished product obtained from aluminum powder. The semi-finished powders were produced by means of the uniaxial hot pressing method. From the components prepared in this way, an extrusion chargé was made by machining in an alloy shell-core system. Permanent bonding of the components and forming the required shape of the composites was carried out using direct hot extrusion under isothermal conditions. It was confirmed that the application of powder metallurgy technology for the production of one or both component materials makes it possible to conduct the extrusion of the components with significantly different plasticity without violating the cohesion of the layers. This approach made it possible to produce layered composites with high-strength properties of the outer layer and with a ductile core. The microstructural state of the components was evaluated, focusing on the continuity of the transition zone between the components. Observations of the separation lines between the layers revealed that the zone between the components was continuous, which was found for both composites, regardless of the examined cross-section. On this basis, it was concluded that the direct hot extrusion process, carried out under the adopted parameters, made it possible to combine the components very well. Selected properties of the layered composites were also determined. It was shown that the proposed method, combining powder metallurgy and hot forming technologies, makes it possible to obtain a continuous connection of components and produce products with properties significantly differentiating in the core and shell zones. These properties can be controlled by appropriate selection of the components, as well as by the method of manufacturing the core. Potential applications of the studied materials include the manufacture of bimetallic components for operation in conditions where significantly different properties of the outer zone and the core are required.

20

Extended friction stir welding applications and the use of an innovative FSW head

Nowak Mirosław, Szostek Paweł, Nowak Marcin

Biuletyn Instytutu Spawalnictwa w Gliwicach

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2022

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Vol. 66, No. 5

61--72

EN

The article presents general information about friction stir welding process (FSW) as a welding method involving the stirring of the weld material, discusses the course of the welding process itself, describes the structure of the FSW joint, presents advantages and disadvantages of the method as well as discusses factors affecting the quality of FSW joints. In addition, the article describes an innovative FSW head (designed by Stirweld (France) and installed on CNC machines) as well as illustrates the operation of the head and enumerates the advantages resulting from the use of the head in comparison with those characteristic of “conventional” friction stir welding machines.

PL

W artykule przedstawiono ogólne informacje na temat metody zgrzewania z mieszaniem materiału zgrzeiny FSW (Friction Stir Welding). Scharakteryzowano przebieg procesu zgrzewania, opisano budowę złącza, przedstawiono i omówiono wady oraz zalety metody, a także czynniki wpływające na jakość połączeń. W publikacji opisano innowacyjną głowicę do zgrzewania FSW firmy Stirweld (Francja), instalowaną na frezarkach CNC. Zilustrowano proces działania głowicy oraz omówiono korzyści wynikające z jej zastosowania w porównaniu ze zgrzewarkami FSW.