Subjects -> EARTH SCIENCES (Total: 771 journals)
    - EARTH SCIENCES (527 journals)
    - GEOLOGY (94 journals)
    - GEOPHYSICS (33 journals)
    - HYDROLOGY (29 journals)
    - OCEANOGRAPHY (88 journals)

EARTH SCIENCES (527 journals)            First | 1 2 3     

Showing 401 - 371 of 371 Journals sorted alphabetically
Physical Geography     Hybrid Journal   (Followers: 8)
Physical Science International Journal     Open Access  
Physics in Medicine & Biology     Full-text available via subscription   (Followers: 15)
Physics of Life Reviews     Hybrid Journal   (Followers: 1)
Physics of Metals and Metallography     Hybrid Journal   (Followers: 18)
Physics of Plasmas     Hybrid Journal   (Followers: 10)
Physics of the Earth and Planetary Interiors     Hybrid Journal   (Followers: 34)
Physics of the Solid State     Hybrid Journal   (Followers: 4)
Physics of Wave Phenomena     Hybrid Journal  
Physics World     Full-text available via subscription   (Followers: 18)
Physik in unserer Zeit     Hybrid Journal   (Followers: 9)
Pirineos     Open Access  
Planet     Open Access   (Followers: 4)
Plasma Physics and Controlled Fusion     Hybrid Journal   (Followers: 7)
Plasma Physics Reports     Hybrid Journal   (Followers: 7)
Polar Record     Hybrid Journal   (Followers: 2)
Positioning     Open Access   (Followers: 4)
Pramana     Open Access   (Followers: 13)
Precambrian Research     Hybrid Journal   (Followers: 7)
Preview     Hybrid Journal  
Proceedings of the Geologists' Association     Full-text available via subscription   (Followers: 6)
Proceedings of the Linnean Society of New South Wales     Full-text available via subscription   (Followers: 2)
Proceedings of the Yorkshire Geological Society     Hybrid Journal   (Followers: 1)
Progress in Earth and Planetary Science     Open Access   (Followers: 15)
Pure and Applied Geophysics     Hybrid Journal   (Followers: 12)
Quarterly Journal of Engineering Geology and Hydrogeology     Hybrid Journal   (Followers: 4)
Quaternary     Open Access  
Quaternary Australasia     Full-text available via subscription  
Quaternary Geochronology     Hybrid Journal   (Followers: 8)
Quaternary International     Hybrid Journal   (Followers: 14)
Quaternary Research     Full-text available via subscription   (Followers: 19)
Quaternary Science Advances     Open Access  
Quaternary Science Reviews     Hybrid Journal   (Followers: 26)
Radiocarbon     Hybrid Journal   (Followers: 13)
Remote Sensing     Open Access   (Followers: 58)
Remote Sensing Applications : Society and Environment     Full-text available via subscription   (Followers: 9)
Remote Sensing in Earth Systems Sciences     Hybrid Journal   (Followers: 6)
Remote Sensing Letters     Hybrid Journal   (Followers: 46)
Remote Sensing Science     Open Access   (Followers: 30)
Rendiconti Lincei     Hybrid Journal  
Reports on Geodesy and Geoinformatics     Open Access   (Followers: 8)
Reports on Mathematical Physics     Full-text available via subscription   (Followers: 2)
Research & Reviews : Journal of Space Science & Technology     Full-text available via subscription   (Followers: 20)
Resource Geology     Hybrid Journal   (Followers: 6)
Resources, Environment and Sustainability     Open Access   (Followers: 2)
Results in Geochemistry     Open Access  
Results in Geophysical Sciences     Open Access  
Reviews in Mineralogy and Geochemistry     Hybrid Journal   (Followers: 4)
Reviews of Modern Physics     Full-text available via subscription   (Followers: 31)
Revista Cerrados     Open Access  
Revista de Ciências Exatas Aplicadas e Tecnológicas da Universidade de Passo Fundo : CIATEC-UPF     Open Access  
Revista de Ingenieria Sismica     Open Access  
Revista de Investigaciones en Energía, Medio Ambiente y Tecnología     Open Access  
Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales     Open Access  
Revista de Teledetección     Open Access  
Revista Geológica de Chile     Open Access  
Revue Française de Géotechnique     Hybrid Journal  
Rock Mechanics and Rock Engineering     Hybrid Journal   (Followers: 7)
Rocks & Minerals     Hybrid Journal   (Followers: 3)
Russian Geology and Geophysics     Hybrid Journal   (Followers: 2)
Russian Journal of Mathematical Physics     Full-text available via subscription  
Russian Journal of Pacific Geology     Hybrid Journal  
Russian Physics Journal     Hybrid Journal   (Followers: 1)
Science China Earth Sciences     Hybrid Journal   (Followers: 3)
Science News     Hybrid Journal   (Followers: 11)
Science of Remote Sensing     Open Access   (Followers: 7)
Scientific Annals of Stefan cel Mare University of Suceava. Geography Series     Open Access  
Scientific Journal of Earth Science     Open Access   (Followers: 1)
Scientific Reports     Open Access   (Followers: 87)
Sedimentary Geology     Hybrid Journal   (Followers: 19)
Sedimentology     Hybrid Journal   (Followers: 14)
Seismic Instruments     Hybrid Journal   (Followers: 1)
Seismological Research Letters     Full-text available via subscription   (Followers: 12)
Soil Dynamics and Earthquake Engineering     Hybrid Journal   (Followers: 14)
Soil Security     Open Access   (Followers: 4)
Solid Earth     Open Access   (Followers: 5)
Solid Earth Discussions     Open Access   (Followers: 1)
Solid Earth Sciences     Open Access   (Followers: 1)
South African Journal of Geomatics     Open Access   (Followers: 2)
Standort - Zeitschrift für angewandte Geographie     Hybrid Journal   (Followers: 3)
Stratigraphy and Geological Correlation     Full-text available via subscription   (Followers: 2)
Studia Geophysica et Geodaetica     Hybrid Journal   (Followers: 1)
Studia Geotechnica et Mechanica     Open Access  
Studia Universitatis Babes-Bolyai, Geologia     Open Access  
Survey Review     Hybrid Journal   (Followers: 6)
Surveys in Geophysics     Hybrid Journal   (Followers: 3)
Swiss Journal of Palaeontology     Hybrid Journal   (Followers: 4)
Tectonics     Full-text available via subscription   (Followers: 15)
Tectonophysics     Hybrid Journal   (Followers: 24)
Tellus A     Open Access   (Followers: 21)
Tellus B     Open Access   (Followers: 20)
Terra Latinoamericana     Open Access  
Terra Nova     Hybrid Journal   (Followers: 5)
The Compass : Earth Science Journal of Sigma Gamma Epsilon     Open Access  
The Holocene     Hybrid Journal   (Followers: 16)
The Leading Edge     Hybrid Journal   (Followers: 1)
Transportation Infrastructure Geotechnology     Hybrid Journal   (Followers: 8)
Turkish Journal of Earth Sciences     Open Access  
UD y la Geomática     Open Access  
Unconventional Resources     Open Access  
Underwater Technology: The International Journal of the Society for Underwater     Full-text available via subscription   (Followers: 1)
Universal Journal of Geoscience     Open Access  
Unoesc & Ciência - ACET     Open Access  
Vadose Zone Journal     Open Access   (Followers: 5)
Volcanica     Open Access  
Water     Open Access   (Followers: 10)
Water International     Hybrid Journal   (Followers: 19)
Water Resources     Hybrid Journal   (Followers: 21)
Water Resources Research     Full-text available via subscription   (Followers: 97)
Watershed Ecology and the Environment     Open Access  
Weather, Climate, and Society     Hybrid Journal   (Followers: 15)
Wiley Interdisciplinary Reviews - Climate Change     Hybrid Journal   (Followers: 33)
World Environment     Open Access   (Followers: 1)
Yearbook of the Association of Pacific Coast Geographers     Full-text available via subscription   (Followers: 2)
Yugra State University Bulletin     Open Access   (Followers: 1)
Zeitschrift der Deutschen Gesellschaft für Geowissenschaften     Full-text available via subscription   (Followers: 3)
Zeitschrift für Geomorphologie     Full-text available via subscription   (Followers: 5)
Zitteliana     Open Access   (Followers: 1)
Землеустрій, кадастр і моніторинг земель     Open Access   (Followers: 1)

  First | 1 2 3     

Similar Journals
Journal Cover
Physics of Metals and Metallography
Journal Prestige (SJR): 0.427
Citation Impact (citeScore): 1
Number of Followers: 18  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 0031-918X - ISSN (Online) 1555-6190
Published by Springer-Verlag Homepage  [2467 journals]
  • Oxidation and Hot Corrosion Behaviour of Ni-Based Superalloy 825 and AISI
           321 Dissimilar Laser Weldment in K2SO4–60% NaCl Molten Salt Environment
           at 650°C

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      Abstract: In waste incinerators and petrochemical plants, one encounters dissimilar weld joints of superalloys and special steels. The operating conditions are such that weld joints are exposed to high temperatures and deposition of salts takes place on the weld joints. In addition, experience shows that many failures take place at the weld joints. Hence it becomes imperative that hot corrosion behaviour of such weldments is studied and underlying mechanisms understood, so that suitable remedial measures can be identified. The present study addresses air oxidation and hot corrosion behaviour of dissimilar laser welded joints of Ni–Fe-based superalloy 825 and AISI 321 under K2SO4 + 60% NaCl at 650°C. The result analysis for reaction products, phase changes the distribution of alloying elements in the corrosion product(s) and the underlying substrate of the hot corroded samples were discussed in detail from the results obtained from cross sectional OM, SEM and XRD, X-ray mapping and EDS point analysis. Corrosion kinetics of the weldment is obtained by thermo-gravimetric technique. Sulphide and dichromate phases form additionally during hot corrosion; the latter, with low relatively low boiling points, may be contributing to loss of Cr from the surface and weight loss.
      PubDate: 2022-11-10
       
  • Thermodynamic Properties Prediction of Fe–Al–Ti Alloys Based on Atom
           and Molecule Coexistence Theory

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      Abstract: The thermodynamic properties for the full composition range of liquid Fe–Ti alloys were determined using the atom and molecule coexistence theory (AMCT). The thermodynamic model was also established to calculate the mass action concentration (activity) of the structural units in the above-mentioned binary alloy system. The temperature dependence of the activity coefficients \(\gamma _{i}^{\theta }\) of Ti dissolved in molten iron to form dilute solutions ( \(0 \leqslant {{x}_{i}} \leqslant 0.01\) ) relative to pure liquid, were also estimated. Simultaneously, the standard Gibbs free energy changes \({{\Delta }_{{{\text{sol}}}}}G_{{{\text{m,}}i}}^{{{\theta }}}\) of dissolving Ti in the iron of liquid Fe–Ti were also studied. The excess molar mixing enthalpy \({{\Delta }_{{{\text{mix}}}}}H_{{{\text{m, Fe}} - {\text{Ti}}}}^{{{\text{ex}}}}\) , the excess molar mixing entropy \({{\Delta }_{{{\text{mix}}}}}S_{{{\text{m, Fe}} - {\text{Ti}}}}^{{{\text{ex}}}}\) , and the excess molar mixing Gibbs free energy \({{\Delta }_{{{\text{mix}}}}}G_{{{\text{m, Fe}} - {\text{Ti}}}}^{{{\text{ex}}}}\) were also studied from 1873 to 2073 K. Meanwhile, the thermodynamic properties of activities and the excess Gibbs free energy of mixing were predicted in the Fe–Al–Ti ternary melts at 1873 K under conditions of various Fe/Al ratios.
      PubDate: 2022-11-10
       
  • Study of the Mechanical Properties of NiTi Modified by Carbon Plasma
           Immersion Ion Implantation Using Nano-Indentation Test and Finite Element
           Method Simulation

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      Abstract: Plasma immersion ion implantation is one of the common methods to enhance the corrosion resistance, mechanical properties, and biological characteristics of NiTi alloys. Herein, the nano-mechanical behavior and distribution of compressive and tensile stress of NiTi alloy samples modified by carbon plasma immersion ion implantation (C-PIII) are analyzed by atomic force microscopy (AFM), nano-indentation test, and finite element method (FEM) simulation. C-PIII produces a modified layer with a thickness of 48 nm. The average surface roughness decreases from 34.023 to 25.180 nm and the hardness and Young’s modulus increase to 80.7 and 21.8%, respectively, after C-PIII. FEM simulation reveals that elastic and plastic deformation similar to that observed experimentally arises from the increase in strength and changes in the surface phases stemming from C-PIII. The larger Young’s modulus and hardness of the C-PIII sample reduces the penetration depth and plastic strain during nano-indentation resulting in a decrease of the compressive residual stress by 46% from –0.619 to –0.313 GPa at the tip of the indenter. Our results show that the durability and service lifetime of NiTi alloys can be improved by C-PIII thus boding well for biomedical applications in harsh environments such as blood vessel stents and bone joints.
      PubDate: 2022-11-10
       
  • Intermetallic Compounds and Mechanical Properties of Mg/Al Dissimilar
           Joints by Friction Stir Welding

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      Abstract: The amount and shape of intermetallic compounds (IMCs) may influence the properties of the Al–Mg dissimilar welded joints. In this paper, friction stir welding with stir tool offset to the Al side was carried out to reduce IMC. The microstructure of joints was observed by OM and SEM. XRD and TEM were applied to do further study on the IMC phases. The result showed that the offset of the stirring tool affected the welding thermal cycle and element diffusion. Intermetallic compounds layer consisting of Al3Mg2 and Al12Mg17 formed in the Al/Mg interface and resulted in the fracture of the joint. Maximum hardness (102HV) appeared in the weld nugget area and the hardness value of the welded joints presented an uneven distribution.
      PubDate: 2022-11-10
       
  • Effect of Mono and Hybrid Reinforcement on Microhardness and Wear Behavior
           of Al–Mn Alloy Based Surface Composites Produced by Friction Stir
           Processing

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      Abstract: In this paper, the wear resistance and microhardness of the hybrid and mono surface composite with Al–Mg–Mn alloy (AA5083) as the matrix material and SiC, Al2O3, Gr, and CNT as the reinforcement material was investigated experimentally. The surface composite was fabricated by friction stir processing (FSP). The microstructure of the prepared specimens was observed using optical microscopy. Mono reinforced surface composite and hybrid reinforced surface composite were tested for their microhardness and wear resistance before and after FSP and the results were compared. The surface composites showed uniform dispersion and finer grain size after FSP in comparison with the as-received AA5083. FSP aided the hybrid reinforced surface composite to increase the maximum microhardness value to 107.5 HV in SiC/Gr reinforcement as compared to the 89.11 HV in mono Gr reinforced surface composite and 75.15 HV in as-received AA5083. The hybrid surface composite also provided enhanced wear resistance in comparison with the mono reinforced surface composite and the base material.
      PubDate: 2022-11-10
       
  • Investigation of Thermal and Antimicrobial Properties of NiTiX (X = Ta,
           Ag, and Nb) Shape Memory Alloys

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      Abstract: In this study, the Ni30Ti50Ta20, Ni30Ti50Ag20 and Ni29Ti50Nb21 shape memory alloys SMAs were produced through the arc-melting method under a high vacuum. The thermal properties and antimicrobial potential for these alloys were investigated. The thermal properties were determined by DSC at different heating rates. According to the DSC results, the austenite phase transformation temperature of Ni30Ti50Ta20 alloy is higher than Ni30Ti50Ag20 and Ni29Ti50Nb21 alloys. The thermal activation energy calculated by Kissinger and Ozawa methods were found as follows: Ea = 156.138 kJ/mol and Ea = 154.37 kJ/mol for Ni30Ti50Ta20 alloy, Ea = 124 kJ/mol and Ea = 123.74 kJ/mol for Ni30Ti50Ag20 alloy, and Ea = 89.43 kJ/mol and Ea = 90.6 kJ/mol for Ni29Ti50Nb21 alloy, respectively. In this study each of alloys exhibited a very strong antifungal ability. When compared by the antibacterial activities; the Ni30Ti50Ta20 alloy was showed higher activity than Ni30Ti50Ag20 and Ni29Ti50Nb21 alloys. It was seen from the Vickers hardness results of the samples that Ni30Ti50Ta20 SMA has the highest value. Optical microscope images of the alloys were taken at three different temperatures. Martesite plates were not found in any of the alloys. In addition, no structural changes were observed with the temperature difference. Based on the obtained results, it is suggested that the alloys have a high potential for biomedical applications to prevent bacterial based infections.
      PubDate: 2022-11-10
       
  • On the Resolution in Strain/Stress Measurements on Bulk Polycrystalline
           Samples by 3-Axis Neutron Diffractometer

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      Abstract: Important resolution properties of the high-resolution 3-axis neutron diffraction set-up were investigated in the frame of feasibility of its use for strain/stress measurements on bulk polycrystalline samples. The strain analysis was carried out by rocking the BPC-analyzer and the neutron signal registered by a point detector. The so-called rocking curve then provided a sample diffraction profile and could reflect the lattice or structural changes. In comparison with a conventional 2-axis set-up, this instrument alternative could be successfully applied, namely, in the strain/stress measurements in bulk samples exposed to an external load, e.g. in tension/compression rig, in aging machine etc. and provide average strain values over a large irradiated volume of the sample.
      PubDate: 2022-11-10
       
  • Effect of Grain Size and Processing Parameters on Critical Strain for
           Austenite Dynamic Recrystallization

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      Abstract: Effect of primary austenite grain size and processing parameters on the critical strain of dynamic recrystallization (DRX) during finishing has been investigated and modeled in the present paper. The stress-strain curves were achieved based on the hot compression experiments in the condition of different temperatures and strain rates with different primary austenite grain size. The deformation temperature and strain rate were normalized as Zener–Hollomon (Z) parameter. The experimental results illustrated that the critical strain for DRX was significantly influenced by the primary austenite grain size but peak strain was not, which has been interpreted based on the nucleation and growth of DRX grains. The modeling parameters have been established based on Sellars’ model, with which the effect of grain size and processing parameters on the critical strain for austenite DRX could be quantitatively calculated, which is helpful to design rolling schedule for promote DRX in order to refine grain size. A seven-passes rolling schedule was designed in the case of only 1.5 reduction ratio. The experimental results confirmed that the grain size was significantly refined by promoting austenite DRX, which are good agreement with modeling calculation.
      PubDate: 2022-11-10
       
  • Influence of La Addition on Order–Disorder Transformation and
           Deformation Softening Behavior of Fe–6.5 wt % Si Alloy

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      Abstract: Because of the existence of B2 and DO3 ordered phases with high hardness and brittleness, the poor plasticity at room temperature brings some difficulties for the industrial production of high silicon steels. The influence of La as a microalloying element on order–disorder transformation and deformation softening behavior of Fe–6.5 wt % Si alloy was studied during warm rolling. The solid drag effect of La reduced the ability of Fe and Si atoms to diffuse to neighboring vacancies in ordered structures, and hindered the nucleation and growth of the B2 ordered phase, resulting in a decrease in the content of B2 phase and size of its particles. Moreover, DSC results indicated that the disappearance of DO3 ordered phase was attributable to the change in order-disorder transformation temperature. The values of nano-hardness decreased from 11.2 GPa for non-La-doped alloy to 5.3 GPa for La-doped alloy, which indicated that the deformation softening ability of Fe–6.5 wt % Si alloy was significantly improved by adding rare earth La.
      PubDate: 2022-11-10
       
  • Microstructure Evolution Characteristic and Control of Iron-Rich Phase in
           Hypereutectic Al–Si Alloy with Co, Mn and P

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      Abstract: In this paper, the microstructure evolutions and control of iron-rich phases in hypereutectic Al‒Si with the composite addition of Co, Mn and P were studied. Firstly, it was observed that Fe-rich compounds in series of Al–20Si–2Fe–xCo alloys (x = 1, 2, 3, and 4 wt %) were effectively promoted to transform from long needle-like β-Al5FeSi and coarse plate–like δ-Al4(Fe,Co)Si2 phases to dendritic α‑Al(Fe,Co,Mn)Si phases. The aspect ratio of Fe-rich particles has been reduced from 22.5 to 12.5 with the addition of Co was 3 wt %. Through the complex modification of Co and Mn, the precipitation of α-Al(Fe,Co,Mn)Si phases in types of Al–20Si–2Fe–3Co–yMn samples was further improved. Cooperating with the effective modification of Co and Mn on Fe-rich particles and the refinement of P element on primary Si, the microstructure of experimental alloys was further optimized. In comparison with basic alloy, the Brinell hardness of Al–20Si–2Fe–3Co–2Mn–0.03P alloy was significantly improved as high as 131 HB, reaching by 61.7%.
      PubDate: 2022-11-10
       
  • On Vitrification Driving Force as a Perspective Glass-Forming Ability
           Criterion for Metallic Glasses

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      Abstract: In this theoretical contribution, authors propose a new glass-forming ability criterion: the vitrification driving force for metallic glasses (VDFMGs) based on the phenomenological discussion of crystallization driving force (CDF). The VDFMGs mathematical expression is the inverse one of CDF (Vitrification and crystallization being opposite phenomena).
      Authors suggest confine its calculation in the temperature interval ΔTl–g = (Tl – Tg) where the crystallization vs. vitrification competition takes place. A case study on various metallic glasses systems revealed high statistical correlations with the cooling rate Rc, Trg, γ, γm, and k (selected as most efficient GFA indicators) and demonstrates its obvious accurate aptitude to quantify the GFAMGs.
      PubDate: 2022-11-10
       
  • Mathematical Modelling for Understanding the Effect of Stress State on
           Relative Slip Activity in HCP Titanium

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      Abstract: In the present work, the effect of applied stress tensor on relative slip activity as a function of crystallographic orientation on the HCP α-titanium is studied. In this statistical model, a discrete set of thousand uniformly distributed orientations are used to calculate the relative contribution of slip activity for the dominant slip systems in terms of Von Mises strain. The total plastic strain is plotted on the standard IPF triangle as a colour contours map, which enables the predictions of the dominant contribution of activity among several slip systems. The model further concludes that statistically the basal and prismatic slip systems are principal slip systems Furthermore, the relative contribution to total strain from prismatic slip system activity is high as compared to basal slip system activity. This behavior can be explained by the lowest critical resolve shear stress of the prismatic slip system for completely random textured HCP titanium.
      PubDate: 2022-11-10
       
  • Multiple Bragg Reflections Are Not Always Negligible and Spurious

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      Abstract: In our contribution we present some important results of an exhaustive neutron diffraction studies of multiple Bragg reflections (MBR) accompanying an allowed as well as forbidden reflections. The MBR-observations were carried out, namely, in the frame of Bragg diffraction optics experiments on cylindrically bent perfect single crystals. It has been found that depending on the thickness and curvature of the crystal slabs and the diffraction geometry (reflection, transmission) many strong multiple reflections can be excited which also could be used as a source of highly monochromatic and highly collimated beams for further high-resolution neutron scattering or radiography experiments.
      PubDate: 2022-11-10
       
  • Study of Structural, Elastic and Thermodynamic Properties of Metal
           Carbides MC (M = Ir, Rh and Ru) Using First-Principles Calculations

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      Abstract: DFT calculations of the metal carbides MC (M = Ir, Rh and Ru) compounds in the rock-salt RS (B1) and Zinc Blende ZB (B3) phases were performed over the structural, elastic and thermodynamic properties. The exchange-correlation functional employed is the generalized gradient approximation of Wu and Cohen (GGA-WC). The structural parameters such as lattice constants (a0), bulk moduli (B0) and its pressure derivative ( \(B_{0}^{'}\) ) were calculated, and the values obtained are in excellent agreement with the experimental and theoretical results. The elastic constants (C11, C12 and C44), Shear modulus (G) and Young’s modulus (E) have also been computed and then compared with the theoretical data reported in the literature. The thermodynamic properties of these compounds were estimated, and the effects of temperature and pressure upon the heat capacities, expansion coefficients and bulk modulus. The longitudinal, transverse and average sound velocities and Debye temperature of these compounds have also been calculated and analyzed.
      PubDate: 2022-11-10
       
  • Microstructure and Tribological Behaviour of NiWCrBSi Coating Produced by
           Flame Spraying

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      Abstract: The application of hard and resistant coatings is a possibility to increase the lifetime of parts exposed to heavy loads and harsh environments. This work is focused on the investigation of mechanical properties of flame sprayed NiWCrBSi coatings, addressing in particular coating microstructure, hardness, friction behaviour and wear mechanisms. Microstructure and phase composition of coatings were characterized by optical microscopy, scanning electron microscopy coupled with energy dispersive X-ray spectroscopy and X-ray diffraction analysis. Microhardness of coated and uncoated samples was measured and their tribological properties were evaluated by ball-on-disk tests under dry conditions at room temperature. The morphology of the worn scar at different sliding conditions was investigated using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy and the corresponding wear profile by 3D profilometry. The coatings presented mainly a heterogeneous lamellar structure, containing inhomogeneities, such as unmelted particles, micro-cracks, oxides and various types of pores. The coatings underwent severe wear at low sliding speeds, where the predominating wear mechanism was identified as massive exfoliation. However, when increasing the sliding speed and the sliding distance, a transition in the predominant wear mechanism was observed, passing from the combination of oxidative/soft abrasive mechanism to fatigue delamination. These results indicate the importance of controlling coating microstructure through process parameters to optimize its tribological behaviour.
      PubDate: 2022-11-10
       
  • Structural Configuration and Phase Stability in Heusler Alloys Mn2YSb (Y =
           Os, Pt)

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      Abstract: The configurations of L21 and XA for Heusler alloys Mn2OsSb and Mn2PtSb were studied and the corresponding cubic phase equilibrium lattice constants were determined. The results show that the XA-type Mn2OsSb and L21-type Mn2PtSb are their cubic ground states, repectively. The calculated elastic constants and drawn three-dimensional Young’s modulus indicate these cubic phase has stable mechanical properties and elastic anisotropy. When the tetragonal deformation is considered, it is found that the tetragonal L21-type structure of Mn2PtSb can further reduce the total energy with respect to the cubic phase, while XA-type structure of Mn2OsSb is still the most stable configuration. The electronic structures show that the cubic XA configuration of Mn2OsSb of present half-metallic characteristics, and the total magnetic moment per molecular unit meets the Slater–Pauling rule.
      PubDate: 2022-11-10
       
  • Temperature Dependences of the High-Frequency Electrical Impedance of
           Cobalt-Based Amorphous Wires with an Inhomogeneous Magnetic Structure

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      Abstract: The effect of a constant axial magnetic field on the temperature dependences of the high-frequency electrical impedance of amorphous cylindrical wires of Co66Fe4Nb2.5Si12.5B15 is studied and discussed. In the region of the ferromagnetic phase transition, the action of an axial magnetic field leads to a significant change in the temperature dependence of the impedance measured at frequencies below 10 MHz. The revealed features are explained by the presence of two magnetic phases with different Curie temperatures and different distributions in the bulk of the wire.
      PubDate: 2022-09-01
       
  • Modeling and an Experimental Study of the Frequency Dependences of the
           Impedance of Composite Wires

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      Abstract: Some results are presented for the computer-aided modeling of the frequency dependences of the impedance of a composite highly conductive weakly magnetic strand thin magnetic coating wire. Modeling was performed within a range of alternating current frequencies from 0.01 to 100 MHz in a broad interval of strand and coating specific electroconductivities and coating magnetic permeabilities. Two characteristic frequencies associated with the existence of two areas with different electrical and magnetic parameters, i.e., the strand and the coating were revealed. A convenient method of determining these frequencies is proposed. Modeling results were compared with the experimental frequency dependences of the impedance of a CuBe/FeCoNi composite wire.
      PubDate: 2022-09-01
       
  • The Effect of Electropulsing-Assisted Ultrasonic Impact Treatment on the
           Microstructure, Phase Composition, and Microhardness of
           Electron-Beam-Welded 3D Printed Ti–6Al–4V Alloy

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      Abstract: X-ray diffraction analysis and transmission electron microscopy have shown the formation of a gradient structure in surface layers during electropulsing-assisted ultrasonic impact treatment (EAUIT) of a weld in Ti–6Al–4V alloy samples prepared by the electron-beam wire additive technology. In particular, nanocrystalline titanium and titanium–iron oxides, and amorphous and nanocrystalline α-phase structures form at a depth of 1–2 µm; a nanocrystalline structure in layers with β + α" and α + β-phases forms at a depth of 2 to 10 µm; and submicro and microcrystalline α-phase structures, at a depth of more than 10 µm. EAUIT of the metal in the weld zone causes iron alloying of 1–2 µm surface layers and increases the microhardness due to an increase in the grain boundary contribution to the hardening due to nanocrystalline and submicro and microcrystalline structure formation in α- and β-phases during processing and hardening due to the precipitation of nanocrystalline titanium–iron oxide and α"-phases.
      PubDate: 2022-09-01
       
  • Structural Hardening of High-Speed Steel

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      Abstract: The hardening (and, correspondingly, fine structure and properties) of high-speed steels as a result of their additional doping with cobalt, thermomechanical treatment, or high-temperature stagewise tempering is compared. It is shown that stagewise short-term high-temperature tempering within a temperature range of 610–630°C, which is not equivalent to standard tempering at 560°C two times for an hour, creates an optimal structural state of steel and is less prolonged, laborious, and energy-consuming.
      PubDate: 2022-09-01
       
 
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