A CoCrCuFeNi high-entropy alloy was successfully welded in this study using fiber laser welding. The effects of the welding parameters on the microstructure and mechanical properties were studied. Three zones were formed: the fusion zone, partial melting zone, and base metal. The base metal exhibited a typical dendrite structure, and the Cu element segregated in the interdendrite. The fusion zone consisted of fine equiaxed crystals and columnar crystals with the same crystalline structure as the base metal. The fusion zone exhibited minimal compositional microsegregation after laser welding. Electron backscatter diffraction results showed that the low-angle grain boundary fraction in the fusion zone increased. Furthermore, some dislocations and dislocation pile-ups were present in the fusion zone, and the densities of the dislocations and dislocation pile-ups were higher than those of the base metal. The hardness of the fusion zone was considerably higher than that of the base metal, while the ultimate tensile strength and elongation values were lower than those of the base metal for all conditions. The ultimate tensile strength and the elongation increased gradually and then decreased with increasing laser power. The maximum ultimate tensile strength exceeded that of the base metal by 90%.
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http://dx.doi.org/10.3390/ma15248777 | DOI Listing |
J Fluoresc
January 2025
Department of Chemistry, College of Science, University of Sulaimani, Qlyasan Street, Sulaymaniyah, Kurdistan Regional Government, 46002, Iraq.
This study highlights the importance of developing sensitive and selective sensors for use in pharmaceutical applications for the first time. A novel iron(III)-complex, constructed from unsymmetrical tetradentate NNN'O type Schiff base ligand (E)-3-((6-aminopyridin-2-yl)imino)-1-phenyl butane-1-one (LH) and its structure of it characterized by using various spectroscopic techniques such as FT-IR, UV-Vis, elemental analysis, conductivity, magnetic susceptibility measurements and the TGA method. The correlation of all results revealed that the coordination of the (LH) with the metal ion in a molar ratio of 1:1 leads to the formation of an octahedral geometry around the metal ions.
View Article and Find Full Text PDFNano Lett
January 2025
Shanghai Frontiers Science Research Base of Intelligent Optoelectronics and Perception, Institute of Optoelectronics, Department of Materials Science, Fudan University, Shanghai 200433, China.
Achieving high mobility while minimizing off-current and static power consumption is critical for applications of two-dimensional field-effect transistors. Herein, a selenium (Se) sacrificial layer is introduced between the rhenium sulfide (ReS) semiconductor and source/drain electrode. With the Se layer and postannealing process, the ReS transistor significantly decreases the off-state current with a substantial increase in the on-state current density.
View Article and Find Full Text PDFJ Am Chem Soc
January 2025
Center for Nanomedicine, Institute for Basic Science (IBS), Seoul 03722, Republic of Korea.
Perpendicular nanochannel creation of two-dimensional (2D) nanostructures requires highly controlled anisotropic drilling processes of the entire structure via void formation. However, chemical approaches for the creation of porosity and defects of 2D nanostructures have been challenging due to the strong basal plane chemical stability and the use of harsh reactants, tending to give randomly corroded 2D structures. In this study, we introduce Lewis acid-base conjugates (LABCs) as molecular drillers with attenuated chemical reactivity which results in the well-defined perpendicular nanochannel formation of 2D TiS nanoplates.
View Article and Find Full Text PDFChem Sci
December 2024
Department of Physics & Chemistry, DGIST Daegu 42988 Korea
Metal-organic frameworks (MOFs), characterized by dynamic metal-ligand coordination bonding, have pivotal roles in catalysis, gas storage, and separation processes, owing to their open metal sites (OMSs). These sites, however, are frequently occupied by Lewis-base solvent molecules, necessitating activation to expose the OMSs for practical applications. Traditional thermal activation methods involve harsh conditions, risking structural integrity.
View Article and Find Full Text PDFHeliyon
December 2024
Department of Mechanics, Electrical Power and Computer, Science and Research Branch, Islamic Azad University, Tehran, Iran.
Dissimilar laser welding of martensitic AISI 1060 carbon steel and Duplex Stainless Steel 2205 was performed based on an experimental and numerical study. The experiments were then conducted based on central composite design experiments (CCD) and analyzed via the response surface methodology (RSM) by considering the effect of laser welding process parameters (incident laser power, speed of welding, nozzle distance and deviation of laser beam) on the weld joint characterization. The experimental results showed that the laser power had a remarkable effect on the melt pool depth.
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