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Structural Characterization and Properties of Al/Fe Multi-Layer Composites Produced by Hot Pressing

Kowalski Wojciech, Paul Henryk, Mania Izabela, Petrzak Paweł, Czaja Paweł, Chulist Robert, Góral Anna, Szlezynger Maciej

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 1

137--144

EN

This study aimed to develop Fe/Al multilayered metallic/intermetallic composites produced by hot pressing under an air atmosphere. Analyses were carried out on the composite plates made up of alternatively situated sheets of AA1050 aluminum alloy and DN04 low carbon steel, which were annealed at 903 K for 2, 5, and 10 h. Annealing was performed to obtain reaction layers of distinct thickness. The samples were examined using X-Ray diffraction and scanning and transmission electron microscope equipped with an energy-dispersive X-Ray spectrometer. To correlate the structural changes with mechanical properties, microhardness measurements in near-the-interface layers were performed. All the reaction layers grew with parabolic kinetics with η-Al5Fe2 intermetallic phase as the dominant component. After annealing for 5 and 10 hours, a thin sublayer of θ-Al13Fe4 phase was also detected.

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Crystal Lattice Rotations Induced by Shear Banding in fcc Metals Deformed at High Strain Rates

Mania Izabela, Paul Henryk, Chulist Robert, Petrzak Paweł, Miszczyk Magdalena, Prażmowski Mariusz

Archives of Metallurgy and Materials

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2023

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Vol. 68, iss. 1

319--329

EN

In this paper, the microstructural and texture changes in polycrystalline CuZn30 alloy, copper, and AA1050 aluminium alloy have been studied to describe the crystal lattice rotation during shear bands formation. The hat-shaped specimens were deformed using a drop-hammer at the strain rate of 560 s-1. Microstructure evolution was investigated using optical microscopy, whereas texture changes were examined with the use of a scanning electron microscope equipped with the EBSD facility. The microstructural observations were correlated with nanohardness measurements to evaluate the mechanical properties of the sheared regions. The analyses demonstrate the gradual nature of the shear banding process, which can be described as a mechanism of the bands nucleation and then successive growth rather than as an abrupt instability. It was found that regardless of the initial orientation of the grains inside the sheared region, a well-defined tendency of the crystal lattice rotation is observed. This rotation mechanism leads to the formation of specific texture components of the sheared region, different from the one observed in a weakly or non-deformed matrix. During the process of rotation, one of the {111} planes in each grain of the sheared region ‘tends’ to overlap with the plane of maximum shear stresses and one of the <110> or <112> directions align with the shear direction. This allows slip propagation through the boundaries between adjacent grains without apparent change in the shear direction. Finally, in order to trace the rotation path, transforming the matrix texture components into shear band, rotation axis and angles were identified.

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Microstructure-related properties of explosively welded multi-layer Ti/Al composites after rolling and annealing

Solecka Monika, Mróz Sebastian, Petrzak Paweł, Mania Izabela, Szota Piotr, Stefanik Andrzej, Garstka Tomasz, Paul Henryk

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 1

art. no. e39, 2023

EN

The processes of rolling and annealing of explosively welded multi-layered plates significantly affect the functional properties of the composite. In current research, fifteen-layered composite plates were fabricated using a single-shot explosive welding technique. The composites were then rolled up to 72% to reduce layer thickness, followed by annealing at 625 °C for varying times up to 100 h. Microstructure evolution and chemical composition changes were investigated using scanning electron microscopy equipped with energy-dispersive spectroscopy. The mechanical properties of the composite were evaluated by tensile testing, while the strengths of individual layers near the interface were evaluated by micro-hardness measurements. After explosive welding, the wavy interfaces were always formed between the top layers of the composite and the wave parameters decreasing as the bottom layers approach. Due to the rolling process, the thickness of Ti and Al layers decreases, and the waviness of top interfaces disappeared. Simultaneously, the necking and fracture of some Ti layers were observed. During annealing, the thickness of layers with chemical composition corresponding to the Al3Ti phase increased with annealing time. A study of growth kinetic shows that growth is controlled by chemical reaction and diffusion. The results of micro-hardness tests showed that after annealing, a fourfold increase of hardness can be observed in the reaction layers in relation to the Ti, while in relation to Al, the increase of hardness is even 15 times greater.

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Impact of the interface on the fatigue life of steel-based explosively welded heterostructured plates

Derda Szymon, Korolczuk Aleksander, Robak Grzegorz, Prażmowski Mariusz, Paul Henryk, Łagoda Tadeusz, Gupta Munish Kumar

Archives of Civil and Mechanical Engineering

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2023

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Vol. 23, no. 3

art. no. e191, 2023

EN

Melted zones, microcracks, shear bands, and elastic incompatibility of explosively welded materials are features that may initialize cracks at the interface and reduce fatigue strength. This study aims to determine the effect of interfacial defect-like structures on the fatigue strength of explosively welded corrosion-resistant plates. Cyclic axial loading was applied to seven distinct layer-by-layer compositions of Ti Gr 1, Zr 700 alloys, and carbon steels. The interfacial wave height as a metric of potential fatigue life influencing factors along with measured strain amplitude was applied as the input quantities for the Machine Learning based model, i.e. the Gaussian process for regression (GPR). This is a novel and successful application of GPR to estimate the effect of interfacial wave height on the fatigue life of explosively welded plates. For the first time, the effect of the interface feature on fatigue life was estimated quantitatively. The Digital Image Correlation technique was applied to measure the field of cyclic strain for the purpose of verifying if a single strain amplitude is representative of a heterostructured plate. It was found that interfacial wave height is an important feature and its increase by 100 µm reduces the fatigue life of analysed plates by 36%. Additionally, to validate the applicability of explosively welded plates to engineering structures under cyclic loading, the experimental fatigue lives were compared with the design curve of the American Society of Mechanical Engineers (ASME) code.

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Influence of Hot Pressing on the Microstructure of Multi-Layered Ti/Al Composites

Kowalski Wojciech, Paul Henryk, Petrzak Paweł, Maj Łukasz, Mania Izabela, Faryna Marek

Archives of Metallurgy and Materials

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2021

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Vol. 66, iss. 4

1149--1156

EN

Metal-intermetallic layered (MIL) composites attract considerable attention due to their remarkable structural and ballistic performance. This study aimed to develop a Ti/Al-based multilayered MIL material by adding ceramic powders, since they can improve the composite’s impact resistance. To this end, an experiment was conducted which a stack of alternating Ti and al sheets bonded by hot pressing; Ti/Al multilayers containing additional layers of Al2O3 and SiC powders were also produced. The samples obtained were examined using electron microscopy techniques. The clads’ mechanical properties were investigated using a Charpy hammer. In the reaction zone, only one intermetallic phase occurred: the Al3Ti phase. The model with an additional Al2O3 layer showed the highest impact energy. none of the Ti/Al clads broke during the Charpy impact test, a result proving their high ductility.

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Experimental investigations of the bonding zone in the explosive welding of a differently structured steel-zirconium platers

Prazmowski Mariusz, Paul Henryk

Journal of Machine Engineering

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2019

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Vol. 19, No. 2

99--110

EN

In this work the results of trials aimed at selecting optimal settings of the explosion welding process of 10 mm thick zirconium (Zr 700 grade) plates with carbon steel (P265GH grade) are presented. A bimetal Zr-steel and trimetal Zr-Ti-steel and Zr-Zr-steel where: 2 mm Ti and 3 mm Zr were used as a technological intermediate layer facilitating the bonding. The research was carried out for as-bonded joints, i.e. immediately following explosion welding. Structural analyses in leyers near the interface were focused on the characteristic of the joint interface. Mechanical properties of the obtained clads were measured with shearing, peel and lateral bending tests. Systematic measurements of microhardness distribution enabled analyzing the strain-hardening of the material resulting from explosion welding both at the bond interface zone and throughout the whole section of the clad. It was established that during explosion welding with 10 mm Zr 700 the application of the 2 mm or 3 mm thick interlayers of Zr70 or Ti grade 1, respectively, allows obtaining a joint with good mechanical properties and optimal characteristic of the interface.