An exceptional combination of low Young's modulus (E ~68 GPa) and high flow strength (σf ~1 GPa) was achieved for a consolidated β-Ti-based metastable Ti-35Nb-7Zr-5Ta (TNZT) alloy subjected to room ...temperature high-pressure torsion (HPT). The mechanical properties of the alloy were studied by quasistatic nanoindentation tests at different strain rates, where a reduction in Young's modulus E ~73 GPa (NHPT10) and E ~68 GPa (NHPT40) is observed together with an increase in plastic deformability (or HPT rotations). The microstructure evolution with increasing shear strain has been investigated. The stabilized bcc β-Ti phase with homogeneous nanostructure distribution was observed leading to a low Young's modulus. Severe straining causes a uniform hardness distribution without any noticeable change in the strength of the material. This study may be useful for developing excellent removable implant materials.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
A novel crack-free Ti-modified Mo alloy with good mechanical properties was fabricated successfully by laser powder bed fusion (L-PBF). The micro-Ti particles dissolve homogeneously into the Mo ...matrix. The homogeneous mixture of Ti in Mo does not allow the formation of any new secondary phases. The presence of Ti increases the resistance to deformation within the grains and hence, eliminates the formation of hot-tearing cracks between Mo grains. The presence of high compressive properties (compressive yield strength (656 ± 9 MPa) and fracture strain (18.2 ± 1.9%)) in the L-PBF Tiμm/Mo alloy sample may be attributed to the presence of a high degree of geometrically necessary dislocations (GNDs). The doping of Ti in Mo not only helps in the successful fabrication of L-PBF Mo but also improves their mechanical properties, which paves the way for the fabrication of high-performance Mo-based alloys by L-PBF via innovative alloy design.
•Nearly full dense Tiμm/Mo alloy without cracks were fabricated by Laser powder bed fusion (L-PBF).•The alloy display nearly homogeneous microstructures and a single Mo phase.•The presence of Ti can increase geometrically necessary dislocations leading to the improvement of mechanical properties.•The alloy exhibits a high compressive yield strength (656 ± 9 MPa) and a good fracture strain (18.2 ± 1.9%).
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
In this work, Al-based composites reinforced with Mg-based metallic glass particles are synthesized by uniaxial hot pressing and their mechanical properties are analyzed. The composite powders were ...consolidated into highly dense bulk specimens at temperatures within the super-cooled liquid region of the metallic glass reinforcement. The uniform distribution of the glassy particles and the good reinforcement–matrix interface lead to a significant strength enhancement with respect to the unreinforced matrix along with good plastic deformation. The relationship between the mechanical properties and the structure is investigated and described by a modified shear lag model incorporating the matrix-strengthening mechanism. The calculations are in good agreement with the experimental results, revealing that the dislocation strengthening in the matrix due to the presence of the metallic glass particles plays a major role in determining the mechanical properties of the composites.
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IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
In this paper, we develop an optimal placement of solar-wind energy systems using restricted Boltzmann machine (RBM). The RBM considers various factors to scale the process of optimal placement and ...enables proper sizing and placement for attaining increased electricity production from both wind and solar systems. The multiobjective criterion from both solar and wind energy farms simulated on MATLAB simulator shows an increased number of accuracies with reduced mean average error and computation time during training and testing. The results show that the RBM achieves improved rate of finding the optimal placement with a lesser cost and computation time of lesser than 2 ms than other methods.
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FZAB, GIS, IJS, IZUM, KILJ, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBMB, UL, UM, UPUK
Nano-/ultrafine-grained carbon nanotube-reinforced titanium (CNT/Ti) composites were synthesized by ball milling and high pressure torsion (HPT) at room temperature. The effects of the number of HTP ...rotations and the weight fraction of CNTs on the microstructure, hardness and tensile properties of the CNT/Ti composites were investigated. Transmission electron microscopy (TEM) revealed that elongated grains with an average length of 100–250 nm parallel to the compression axis of HPT and a thickness of 10–25 nm are formed in CNT/Ti composites when CNT contents ranging from 0.3 wt% to 1.0 wt%. With increasing CNT contents, the grain size of Ti is refined, and the microhardness and tensile properties of the composites increase. Evaluating the mechanical properties of the CNT/Ti composites with 0.7 wt% CNTs after 20 rotations indicates a high tensile strength of 872 ± 5 MPa. Cs-corrected high resolution TEM of the interfaces between Ti and the CNTs after HPT reveals a gradual transition from the lattice planes of hexagonal Ti to those of the CNTs. The strengthening mechanisms are discussed from the aspects of matrix grain refinement, distribution of the CNTs and the CNT-Ti interfaces obtained during ball milling and HPT processing.
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IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK, ZRSKP
•Tensile property of Fe49.9Co35.1Nb7.7B4.5Si2.8 glassy particles reinforced Al-based 2024 AA matrix composites.•Fe49.9Co35.1Nb7.7B4.5Si2.8 has high crystallization temperature and is held amorphous ...after hot consolidation.•Improved tensile property for the glass reinforced composite.
The mechanical properties of Al-based composites reinforced with different volume fractions of Fe49.9Co35.1Nb7.7B4.5Si2.8 glassy particles are investigated under tensile loading. The results reveal a significant strengthening of the composites with respect to the unreinforced Al-based matrix. The comparison of the mechanical data with those regarding other Al-based composites reinforced with glassy particles indicates that metallic glasses are not only effective reinforcements under compression but also under tensile loading.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UL, UM, UPCLJ, UPUK
Abstract In this work, we report the development of ZnO NPs by using environmentally friendly SCS using Mimosa pudica (MP) leaves. The obtained ZnO-MP-NPs were subjected to extensive characterization ...techniques such as PXRD, BET, SEM, & TEM. Further, ZnO-MP-NPs were evaluated for their antioxidant ability by DPPH method. Their anticancer capability was assessed by MTT assay on human breast cancer cell ine MCF-7. The results indicated the potential applications of ZnO-MP-NPs both as antioxidant and anticancer agents.
Tungsten heavy alloy composite was developed by using novel CoCrFeMnNi high-entropy alloy as the binder/reinforcement phase. Elemental tungsten (W) powder and mechanically alloyed CoCrFeMnNi ...high-entropy alloy were mixed gently in high energy ball mill and consolidated using different sintering process with varying heating rate (in trend of conventional sintering < microwave sintering < spark plasma sintering). Mechanically alloyed CoCrFeMnNi high-entropy alloy have shown a predominant face-centered cubic (fcc) phase with minor Cr-rich σ-phase. Consolidated tungsten heavy high-entropy alloys (WHHEA) composites reveal the presence of Cr–Mn-rich oxide phase in addition to W-grains and high-entropy alloys (HEA) phase. An increase in heating rate restricts the tungsten grain growth with reduces the volume fraction of the Cr–Mn-rich phase. Finally, spark plasma sintering with a higher heating rate and shorter sintering time has revealed higher compressive strength (~2041 MPa) than the other two competitors (microwave sintering: ~1962 MPa and conventional sintering: ~1758 MPa), which may be attributed to finer W-grains and reduced fraction of Cr–Mn rich oxide phase.
Sustainable TiC-Fe-based cermets have been fabricated by adopting an Additive Manufacturing route based on laser powder bed fusion technology (L-PBF). The objective is to produce crack-free cermet ...components by employing novel multiple laser scanning techniques with variations in laser process parameters. Electron backscatter diffraction analysis (EBSD) was used to study the microstructure and microtexture evolution with variations in laser process parameters. The investigation revealed that adjusting the preheating scan speed (PHS) and melting scan speed (MS) influenced the growth and nucleation of TiC phases. Lowering these speeds resulted in grain coarsening, while higher scan speeds led to grain refinement with larger sub-grain boundaries. Moreover, a high scanning speed increases the degree of dislocation density and internal stress in the fabricated cermet parts. Notably, it is revealed that decreasing the laser scan speed enhanced the proportion of high-angle grain boundaries in the cermet components, signifying an increase in material ductility.
•EBSD and SEM techniques were applied to investigate “green” TiC-based cermets.•Influence of multiple laser scan speed on cermets microstructure.•Significant grain refinement with increasing laser scan speed.•Lower laser scan speed decreases TiC bimodal morphology.•Subtle change in dislocation density as a function of laser scan speed.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
The evolution of microstructure and texture during selective laser melting (SLM) of silver alloy—sterling silver 925 (AM Ag925) has been investigated and analyzed
vis-à-vis
cast sterling silver (AC ...Ag925). The microstructure of AM Ag925 was characterized by a single-phase silver-rich face-centered cubic solid solution with dendritic morphology, along with some locally distributed micro-segregated copper–germanium (Cu–Ge)-rich regions. Each adjacent dendritic feature consists of Ag–Cu-rich and Ag–Ge-rich regions and appears as alternate dark and bright regions. On the other hand, the as-cast AC Ag925 microstructure comprises Ag and Cu phases. Specific heat treatment was employed, which led to an equiaxed microstructure in AM Ag925 with Cu distributing along grain boundaries while the microstructure of AC Ag925 had Cu precipitates inside the matrix. Bulk texture studies revealed that the solidified textures were very weak for AM Ag925, and a random texture is observed. On the other hand, for the AC Ag925 specimens, a typical fiber texture is observed. Both AC Ag925 and AM Ag925 showed significant deviation from
100
solidification texture and influences the mechanical properties.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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