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The influence of high-pressure torsion (HPT) and annealing on microstructure, texture and thermal stability of an immiscible composite Cu43%Cr alloy was studied using electron backscatter diffraction, X-ray diffraction and microhardness measurements. As-received alloy samples were subjected to HPT and subsequent annealing treatment in the range of 210-850°C for 1 h in order to develop ultrafine-grained (UFG) microstructures and highlight their thermal stability. The Cu and Cr grains were refined to ~0.45 and ~0.39 µm, respectively and exhibited equiaxed morphology. The crystallographic texture was of shear type in both Cu and Cr with the domination of C and F orientations, respectively. The UFG microstructure and texture were retained in the Cu43%Cr alloy up to 850°C. The global results show that the immiscible composite Cu43%Cr alloy exhibits a high thermal stability up to 850°C. The evolution of the microstructure, texture and thermal stability of the UFG Cu43%Cr alloy was compared to published data and available models. [ABSTRACT FROM AUTHOR]

A Cu-1Cr-0.1Zr alloy has been subjected to ECAP processing via route Bc and aging at 250-800°C. Electron BackScatter diffraction (EBSD), Transmission Electron Microscopy (TEM) and X-Ray Diffraction Line Profile Analysis (XRDLPA) techniques have been used to unveil some peculiarities of the grain and subgrain structure with a special emphasis on the comparison of the grain size estimated by the three techniques. For the alloy ECAP processed and aged up to 16 passes, the grain size (from EBSD, 0.2 < d < 5 µm), subgrain size (from TEM, d ~ 0.75 µm) and "apparent" average crystallite size (from XRDLPA, d < 0.25 µm) are manifestly different. The results were compared to the published data and analyzed based on the fundamental aspects of these techniques. [ABSTRACT FROM AUTHOR]

The effect of annealing on the microstructure and the texture development was investigated in a particle containing AA3104 aluminium alloy. The samples were processed at room temperature by high-pressure torsion (HPT) up to ten turns. The nucleation of new grains was analyzed by a transmission electron microscope equipped with a system for local orientation measurements and a heating holder.

The review offers a comprehensive analysis of additive manufacturing (AM) processes in the application of high-entropy alloys (HEAs). HEAs have gained considerable attention in recent years due to their unique mechanical and physical properties. We provide the historical background and a clear definition of HEAs, outlining their development over time. The focus is concentrated on examining the utilization of AM processes in HEAs. Specifically, three prominent AM techniques are discussed: electron-beam processes, laser-processed HEAs, and wire-arc additive manufacturing. Each technique is explored in detail, including its advantages, restrictions, and current applications within the HEAs field. An attention is stressed on the significance of AM-process parameters during the fabrication of HEAs. Parameters such as laser power, scanning speed, and powder-feed rate are analysed for their influences on the microstructure and mechanical properties of the final product. The post-processing techniques for additive-manufactured HEAs are considered. The importance of steps such as heat treatment, surface finishing, and machining in achieving the desired material properties and dimensional accuracy in AMproduced HEA components is underlined. Overviewing the HEAs, their application in AM processes, the influence of process parameters, and post-processing considerations, this work can act as a useful source of information for researchers on the way to amendment of the understanding and implementation of AM in the HEAs. [ABSTRACT FROM AUTHOR]

The layers near the interface of explosively welded plates were investigated by means of microscopic observations with the use of transmission electron microscopy (TEM) equipped with energy dispersive spectrometry and scanning electron microscopy equipped with electron backscattered diffraction facility (SEM/EBSD). The metal compositions based on carbon or stainless steels (base plate) and Ti, Zr and Ta (flyer plate) were analyzed. The study was focused on the possible interdiffusion across the interface and the changes in the dislocation structure of bonded plates in the layers near-the-interface.

Laser cladding is an alternative method to other cladding techniques such as Plasma Transfer Arc (PTA) or blowtorch for surface treatment in the glass industry. It aims to produce dense, high-quality coatings on a non-planar surface without affecting its thermal and mechanical properties. In this study, Ni-based coatings were coated onto Cu-Ni-Al substrate using a 3 JET nozzle technique. During laser cladding, good metallurgical bonding is necessary to ensure the further surfacing process technique. A microstructural analysis was conducted, and the mechanical properties were then evaluated with microhardness analysis to link process parameters to coating bonding quality. A calculation of the power attenuation attempts to explain the impact of the powder distribution on the bonding. This work revealed that a chemical dilution zone exists between coating and substrate and is necessary for perfect metallurgical bonding. The heterogeneous bonding, observed through the section, along the curved interface coating/substrate, has been linked to the Gaussian distribution of the powder that attenuates the input power. The attenuated power was measured all along the interface. 35 Ref., 2 Tabl., 10 Fig. Лазерне наплавлення є альтернативним методом наплавлення до таких, як плазмово-дугове або паяння. Воно спрямовано на отримання щільних високоякісних наплавлень на неплоских поверхнях без впливу на їх механічні властивості. У цьому дослідженні наплавлення матеріалу на основі Ni були нанесені на підкладку Cu-Ni-Al за допомогою 3-струменевого сопла. Під час лазерного наплавлення необхідне хороше металургійне зчеплення для забезпечення подальшої техніки процесу наплавлення. Було проведено мікроструктурний аналіз, а також оцінено механічні властивості за допомогою аналізу мікротвердості, щоб зв’язати параметри процесу з якістю зчеплення покриття. Розрахунок ослаблення потужності дає змогу пояснити вплив розподілу порошку на зчеплення. Ця робота показала, що між наплавленням і підкладкою існує зона хімічного розчинення, яка необхідна для ідеального металургійного з’єднання. Гетерогенне зчеплення, що спостерігається через ділянку, вздовж вигнутої поверхні розділу покриття/підкладка, пов’язане з Гауссовим розподілом порошку, який послаблює вхідну потужність. Ослаблену потужність вимірювали по всьому інтерфейсу. Бібліогр. [ABSTRACT FROM AUTHOR]