Subjects -> METALLURGY (Total: 58 journals)
Showing 1 - 10 of 10 Journals sorted alphabetically
Acta Metallurgica Slovaca     Open Access  
Advanced Device Materials     Open Access   (Followers: 3)
American Journal of Fluid Dynamics     Open Access   (Followers: 48)
Archives of Metallurgy and Materials     Open Access   (Followers: 9)
Asian Journal of Materials Science     Open Access   (Followers: 5)
Canadian Metallurgical Quarterly     Hybrid Journal   (Followers: 20)
Complex Metals     Open Access   (Followers: 2)
Corrosion Communications     Open Access  
Energy Materials : Materials Science and Engineering for Energy Systems     Hybrid Journal   (Followers: 19)
Handbook of Magnetic Materials     Full-text available via subscription   (Followers: 2)
Indian Journal of Engineering and Materials Sciences (IJEMS)     Open Access   (Followers: 10)
International Journal of Metallurgy and Alloys     Full-text available via subscription   (Followers: 3)
International Journal of Metals     Open Access   (Followers: 6)
International Journal of Minerals, Metallurgy, and Materials     Hybrid Journal   (Followers: 8)
International Journal of Mining and Geo-Engineering     Open Access  
Ironmaking & Steelmaking     Hybrid Journal   (Followers: 4)
ISIJ International - Iron and Steel Institute of Japan     Full-text available via subscription   (Followers: 23)
JOM Journal of the Minerals, Metals and Materials Society     Hybrid Journal   (Followers: 32)
Journal of Advanced Joining Processes     Open Access  
Journal of Central South University     Hybrid Journal   (Followers: 1)
Journal of Cluster Science     Hybrid Journal  
Journal of Iron and Steel Research International     Hybrid Journal   (Followers: 7)
Journal of Materials & Metallurgical Engineering     Full-text available via subscription   (Followers: 1)
Journal of Materials Processing Technology     Hybrid Journal   (Followers: 19)
Journal of Metallurgical Engineering     Open Access   (Followers: 2)
Journal of Sustainable Metallurgy     Hybrid Journal   (Followers: 3)
Materials Science and Metallurgy Engineering     Open Access   (Followers: 7)
Metallurgical and Materials Engineering     Open Access  
Metallurgical and Materials Transactions A     Hybrid Journal   (Followers: 41)
Metallurgical and Materials Transactions B     Hybrid Journal   (Followers: 30)
Metallurgical and Materials Transactions E     Full-text available via subscription   (Followers: 2)
Metallurgical Research & Technology     Full-text available via subscription  
Metallurgical Research and Technology     Full-text available via subscription   (Followers: 6)
Metallurgy and Foundry Engineering     Open Access   (Followers: 1)
Mining, Metallurgy & Exploration     Hybrid Journal  
Powder Diffraction     Full-text available via subscription   (Followers: 1)
Powder Metallurgy     Hybrid Journal   (Followers: 33)
Powder Metallurgy and Metal Ceramics     Hybrid Journal   (Followers: 7)
Powder Metallurgy Progress     Open Access   (Followers: 5)
Rare Metals     Hybrid Journal   (Followers: 2)
Revista de Metalurgia     Open Access  
Revista del Instituto de Investigación de la Facultad de Ingeniería Geológica, Minera, Metalurgica y Geográfica     Open Access  
Revista Remetallica     Open Access  
Russian Metallurgy (Metally)     Full-text available via subscription   (Followers: 4)
Science and Technology of Welding and Joining     Hybrid Journal   (Followers: 4)
Soldering & Surface Mount Technology     Hybrid Journal   (Followers: 1)
Stainless Steel World     Full-text available via subscription   (Followers: 17)
Transactions of the IMF     Hybrid Journal   (Followers: 14)
Transactions of the Indian Institute of Metals     Hybrid Journal   (Followers: 4)
Tungsten     Hybrid Journal  
Universal Journal of Materials Science     Open Access   (Followers: 1)
Welding in the World     Hybrid Journal   (Followers: 4)
Welding International     Hybrid Journal   (Followers: 7)
Вісник Приазовського Державного Технічного Університету. Серія: Технічні науки     Open Access  
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Metallurgical and Materials Transactions A
Journal Prestige (SJR): 1.093
Citation Impact (citeScore): 2
Number of Followers: 41  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1543-1940 - ISSN (Online) 1073-5623
Published by Springer-Verlag Homepage  [2469 journals]
  • Correction to: Transient Stress Relaxation Test to Identify Material
           Constants in Dislocation Density Model

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      PubDate: 2022-06-01
       
  • Thin Strip vs Direct Chill Casting: The Effects of Casting Cooling Rate on
           the As-cast Microstructure of AA6005 Al–Si–Mg Alloy

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      Abstract: Abstract Aluminum AA6005 sheet produced by Thin Strip (TS) casting was compared to the slabs produced by Direct Chill casting in the as-cast state. Higher cooling rates experienced before, during, and after the solidification for the TS cast sheet showed a finer grain size, smaller secondary dendritic arm spacing, improved solute supersaturation, and a lack of \(\hbox {Mg}_{{2}}\) Si constituents at the grain boundary. These findings showed the effects of cooling rate in the casting process on the as-cast microstructure and provided a basis for further heat-treatment optimization of the TS cast sheet.
      PubDate: 2022-06-01
       
  • Effect of Overheating Events on Microstructure and Low-Cycle Fatigue
           Properties of a Nickel-Based Single-Crystal Superalloy

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      Abstract: Abstract Micro-mechanical response to overheating events is an important factor when considering the serviceable life of aero-engine components. A key lifing consideration is the low-cycle fatigue (LCF) behavior of nickel-based single-crystal superalloy components. In this study, the LCF response was investigated at different overheating temperatures (1100 to 1300 °C) and times (30 to 120 min). The overheating events had an impact on the γ' phase content, which was observed to decrease with the increase in overheating temperature and time (fully dissolving at 1300 °C). Due to the dissolution of γ' precipitates, the average γ' size was shifted to larger values, however, the subsequent cooling post the overheating events resulted in the formation of tertiary γ' and a bimodal particle distribution. During the LCF tests, that were performed after the overheating exposure, either cyclic hardening or softening was observed. It could be concluded that overheating exposures had no significant effect on the fracture features. However, overheating events resulted in a decrease of LCF properties, which was correlated to the local dislocation response.
      PubDate: 2022-06-01
       
  • The Defining Role of Micro-fissures on the Mechanical Behavior of
           Laser-Welded Fully Austenitic Stainless Steel

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      Abstract: Abstract Laser-welded fully austenitic stainless steel (AISI 316LN) weldments revealed the presence of micro-fissures. They appeared at the grain boundaries, near the center of the welds. The grain boundaries, however, did not contain second phase or micro-segregation. The relative presence of micro-fissures decreased with increasing weld heat input. Spatial locations of the micro-fissures and their relative presence were associated with local misorientations and, in particular, with grain reference orientation deviation. Microstructural and microtextural studies indicated that solidification shrinkage was the origin of the micro-fissures in the laser welds. The use of sub-size tensile specimens (of 5- and 1-mm gauge length) with digital image correlation (DIC) related the presence of micro-fissures with mechanical property degradation by the appearance of strain localizations. This was further confirmed by analytical solutions and finite element analysis of critical flaw size and critical stress for fracture.
      PubDate: 2022-06-01
       
  • High-Speed Erichsen Testing of Grain-Refined 301LN Austenitic Stainless
           Steel Processed by Double-Reversion Annealing

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      Abstract: Abstract Austenitic Cr–Ni stainless-type 301LN steel was subjected to a double-reversion annealing (DRA) treatment to develop bulk grain-refined microstructures. The tensile properties and formability of the DRA structures were determined by high-speed tensile and Erichsen cupping tests at a strain rate of 1.5 s−1 (50 mm s−1) and compared with those of coarse-grained steel. Detailed microstructural features of the DRA structures were characterized using the electron backscatter diffraction technique and X-ray diffraction analysis. The DRA structures achieved by annealing for 1 second at 800 °C and 900 °C exhibited a superior combination of yield (~ 950 and 770 MPa, respectively) and tensile (~ 1050 and 950 MPa, respectively) strengths and ductility (~ 35 and 40 pct, respectively, as well as reasonable Erichsen index values under high-speed biaxial strain. Due to adiabatic heating, the DRA structures had higher austenite stability during high-speed stretch forming, i.e., were less prone to strain-induced martensitic transformation. The finite-element method (FEM) was used to conduct coupled field thermomechanical analyses of the high-speed deformation processes for the coarse-grained and DRA structures. Comparison of the FEM analyses with the experimental results revealed a considerable influence (~ 20 pct) of martensitic transformation on the adiabatic temperature rise. The balance of the yield strength and Erichsen index value of the developed nanograined microstructure is comparable to that of coarse-grained commercial steel.
      PubDate: 2022-06-01
       
  • Twin Instability and Its Effect on the Dislocation Behavior of UFG
           Austenitic Steel Under Charpy Impact Test

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      Abstract: Twinning-induced plasticity (TWIP) steel offers high strength and ductility. However, in this study, deformation-induced detwinning was studied to prove that not all twins significantly benefit the mechanical properties. The quasi in situ observation results indicated that submicron-sized twins were unstable during Charpy impact loading. In contrast to the TWIP concept, analysis of the geometrically necessary dislocation evolution associated with detwinning revealed that unstable twins have negligible influence on the pile-ups of dislocations, offering a limited strengthening effect. Graphical
      PubDate: 2022-06-01
       
  • Phase-Field Simulation of D019-Co3W Precipitation in Co–Al–W
           Superalloys

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      Abstract: The γ′-Co3(Al, W) precipitates embedded in the γ matrix are a preferred morphology in Co–Al–W superalloys, while the stable χ (D019-Co3W) phase precipitates from the metastable γ′ phase or γ matrix during long-term aging at high temperature. The χ phase from precipitation to growth and coarsening in Co–10Al–10W at. pct alloy is studied by a phase-field model coupled with the sublattice free energy. The ordering of D019 is faster than the component occupation on the sublattice. The equilibrium partitioning ratios (PR) of elements show that W partitions into the χ phase. With increasing temperature from 1073 K to 1173 K, PR changes from 13.9 to 9.2, and Al partitions into the γ matrix with PR changing from 0.0086 to 0.0717. The diffusion potential explains the directional coalescence of the χ phase along the \([111]_{\gamma }\) direction, and indicates that the elastic contribution is dominant in W diffusion and that the chemical contribution is dominant in Al diffusion. The composition interface of the γ/χ phase is widened during Ostwald ripening of the strip-shaped χ phase. The straightforward view of χ phase precipitation helps in understanding the complex phase structural transformation in Co-based superalloys. Graphical
      PubDate: 2022-06-01
       
  • Tensile Deformation Modeling of a Homogenized Cast Alloy 625: Effects of
           Large Grain Size

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      Abstract: Abstract In the present study, tensile deformation behavior of a coarse-grained (> 1 mm) cast alloy 625 has been investigated by applying empirical and physics-based models. The experimental stress-strain data of the alloy at different deformation temperatures are acquired from uniaxial tensile testing up to 700 °C. The plastic strain region of the alloy’s flow stress (σ) curve shows a significant deviation from the traditional Holloman equation. Parallelly, a distinctive hump in the strain-hardening (θ) curve is also observed after the initial steep drop. Dislocation density-based phenomenological modeling is adopted to ascertain the mechanisms governing plastic deformation of the alloy. The hump in strain-hardening curve is related to the combined effects of low-stacking fault energy of the material and large size grains, which led to deform the material with a smooth transition from restricted single slip at onset of plastic deformation to duplex slip and finally to multiple slips at later stages. As the deformation progresses, this transition results in a smooth exponential drop in the dislocation mean-free path. Transition in slip activity is confirmed through SEM and TEM studies. Further, when the deformation temperature increases, there is an increase in the rate of dynamic recovery and the rate at which single- → multiple-slip transition attains. The microstructural studies of the tensile-fractured samples indicate that the carbide/matrix and carbide/grain boundary interfaces play a crucial role in crack nucleation and propagation during the deformation. Notch tensile testing revealed that introducing a stress raiser would localize the strain and can cause dislocations to glide with a lowered initial mean-free path on multiple-slip systems from the very beginning of plastic deformation.
      PubDate: 2022-06-01
       
  • 3-D Mathematical Modeling of the Effect of Shunt Plate Hole Distribution
           and Magnetic Field on Transport Phenomena Within DC Casting of Magnesium
           Alloy Slab

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      Abstract: Abstract Due to the nonaxisymmetric feature of slabs, the macrotransport phenomena during direct chill (DC) casting are more complex than the macrotransport phenomena of round billets and are tightly associated with their dimensions, width-thickness ratio and even the structure of the shunt plate used to feed the melt to the slab edge. In the present research, aiming to find the desirable structure of the shunt plate and clarify how the form of the magnetic field (MF) affects the transport phenomena, a 3-D coupled mathematical model was set up and used to study the fluid flow, heat transfer and solidification characteristics during electromagnetic DC casting of a magnesium alloy slab with dimensions of 1200 mm (width) × 400 mm (thickness). The effects of the hole distribution of the shunt plate under MF or no MF and different forms of MF on the corresponding physical fields were studied systematically. The predicted results, including the Lorentz force distribution, macro-flow and temperature fields, cooling curve and sump depth, were presented and compared. The results indicated that reducing the holes facing the wide surface was helpful for obtaining desirable variations, such as more homogeneous melt flow and temperature fields, shallower sump depth and faster cooling rate. Using a specific out-of-phase pulsed magnetic field also promoted the above variations more than other forms of magnetic field.
      PubDate: 2022-06-01
       
  • Transient Stress Relaxation Test to Identify Material Constants in
           Dislocation Density Model

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      Abstract: Abstract The constitutive behavior of metallic materials in terms of dislocation kinetics can be successfully described using a dislocation density-based model. Although the kinetics of thermally activated plastic deformation is well described by such models, the number of material constants associated with the model leads to non-unique solution set. In the present work, transient stress relaxation test is used to identify rate-dependent material parameters. The stress relaxation test, when used in conjunction with stress–strain curve can reduce the uncertainty associated with parameter identification. The proposed methodology is demonstrated using aluminum alloys subjected to severe plastic deformation processes such as cryorolling and constrained groove pressing. Kocks–Mecking–Estrin (KME) dislocation density model is implemented as a user subroutine in commercial finite element analysis software. The parameter identification procedure is validated by comparing the experimental results of monotonic tensile and limiting dome height tests. Using dislocation density model, it is shown that unlike the general understanding, the limiting strain is not related to the strain hardening exponent. The limiting strain correlates only with the extent of dynamic recovery, a component of strain hardening.
      PubDate: 2022-06-01
       
  • A Novel In Situ (Al3Ni + Al3Ti)/Al Composite Inoculant and Its Effects on
           the Microstructure, Damping and Mechanical Properties of Zn–Al Eutectoid
           Alloy

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      Abstract: A novel in situ (Al3Ni + Al3Ti)/Al composite inoculant was fabricated, and its effects on the microstructure, damping and mechanical properties of the Zn–Al eutectoid alloy (ZA22) were systematically studied. It was found that due to the unique combined effect of Al3Ni and Al3Ti particles, the novel inoculant had an efficient refining effect on the ZA22 alloy. When 0.6 wt pct inoculant was added, the best refining effect was achieved, and the average size of the α phase in the ZA22 alloy could be reduced to 10 μm (0.1 times that of the original ZA22 alloy). Compared with the original ZA22 alloy, the tensile strength, elongation, Vickers hardness and damping at high temperatures of the inoculated ZA22 alloy with the best refining effect were increased by 19, 264, 27 and 80 pct, respectively, whereas the damping at low temperatures was reduced by 50 pct. Based on in depth microscopic observation, correlated mechanisms were discussed in detail. This study can provide ideas and theoretical basis for the design of novel inoculants and the fabrication of high damping alloys with excellent mechanical properties. Graphical
      PubDate: 2022-06-01
       
  • Evidence of Homogeneous Microstructures in Ti6Al4V Alloy During Shear
           Deformation

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      Abstract: Abstract Free-end torsion tests were conducted for Ti6Al4V (Ti64) alloy at temperatures of 298 K, 673 K, and 873 K for different strains ranging from 0.22 to 0.99. The microstructure and texture evolution as a function of torsional deformation have been investigated in the present study. A near-equiaxed homogeneous microstructure was observed after deformation at all temperatures. However, the grains were observed to be aligned along the direction of shear stress at larger deformation strains. Dynamically recrystallized (DRX) grains were observed in the samples at higher deformation temperatures, and these were found to be significant at 873 K for strains > 0.66. Dynamic transformation of α → β was also observed during deformation at a temperature of 873 K. The initial fiber texture got rotated toward the ideal B fiber orientation, and reached at the ideal C2 fiber orientation after deformation for a maximum strain of 0.99. The deformation texture was further simulated through the Visco plastic self-consistent (VPSC) method, and it was found that the basal slip was the dominant deformation mode followed by prismatic and both pyramidal <c+a> I and II slip systems. The flow stress decreased with increase in the temperature of deformation, and a significant flow softening was observed during deformation at 873 K.
      PubDate: 2022-06-01
       
  • A Dual-Phase Press-Hardening Steel with Improved Mechanical Properties and
           Superior Oxidation Resistance

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      Abstract: Abstract A dual-phase steel (martensite and ferrite) was designed and manufactured for the hot-forming application in automobile. When the quenching from an intercritical temperature of 825 °C produced about 19 pct fraction of ferrite grains and 80 pct martensite in this steel, such a dual-phase microstructure could ensure that both uniform and post-uniform elongations are decent sufficiently without deteriorating strength, i.e., achieving the best mechanical combination of 1762 MPa ultimate tensile strength (UTS) and 11.2 pct total elongation (TE), which is far better than 22MnB5. The straining behavior of ferrite and martensite during deformation is then discussed on the basis of microstructural parameters. Moreover, much thinner oxide layer, less than 1.6 μm thickness, was formed on the steel after the hot forming than that on 22MnB5, because much lower soaking temperature was employed to produce the dual phase in this steel and the denser/thicker Si/Cr-rich oxide band formed at the bottom of layer, both could greatly reduce the oxidization during hot forming.
      PubDate: 2022-06-01
       
  • Microstructure and Crystallography of a Carbide-Free Bainite Steel Under
           the Effect of Stress

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      Abstract: Abstract Stress-affected bainite transformations were conducted on a Gleeble 3800 simulator, and the effects of different stress states (compressive, tensile, elastic, and plastic stresses) on the microstructural evolution and crystallography of a carbide-free bainite steel were investigated by optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM), and electron backscattering diffraction (EBSD). The results show that both compressive and tensile elastic stresses increase the thickness of bainite plates due to the additional mechanical driving force induced by the applied stress, and there is no significant difference between the effects of the two types of stress. Although prior deformation was reported to refine the bainite plates, the plastic stress, which induced prior deformation, coarsens the bainite plates because the effect of mechanical driving is more significant. The size of blocky martensite is refined and the length of bainite sheaves increases under the effect of stress, while the size of blocky RA is almost unaffected. In addition, EBSD results show that the orientation relationship between austenite and bainite ferrite is closer to the Nishiyama–Wassermann (N–W) relationship than to the Kurdjumov–Sachs (K–S) relationship for the stress-affected specimens. Strong variant selection occurs when a stress is applied during bainite transformation. Moreover, the elastic stress slightly decreases the hardness, while the plastic stress increased the hardness.
      PubDate: 2022-06-01
       
  • The Impact of Rolling at Temperature on Conductivity and Texture in
           Nanolamellar Cu/Nb Bimetallic Composites

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      Abstract: Abstract Warm rolling is used to identify whether reductions in dislocation content would provide a significant impact on conductivity in accumulatively roll-bonded Cu-Nb nanolaminates. In addition, the impact of temperature on mechanical properties and interfacial texture is also quantified. Although temperature has a strong effect on dislocation content and mechanical properties, it is shown that length scale and volume fraction are most critical to defining the conductivity of the nanolaminate. Rolling at temperature reduced the flow stress of the material while maintaining the interfacial and layer structure, indicating that warm rolling can increase the ability to process the nanolaminates without reducing conductivity.
      PubDate: 2022-06-01
       
  • Electrochemical Behavior of SLM Ti–6Al–4V Alloy After Long Time of
           Immersion in Lactic Acid Environment

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      Abstract: Abstract The corrosion behavior of selective laser melted Ti–6Al–4V alloy (SLM Ti–6Al–4V) was assessed in 0.1 M lactic acid + 0.1 M NaCl environment (pH 2.5) after 1150 hours of immersion at 37 °C and was compared with that of wrought Ti–6Al–4V alloy. Corrosion potential Ecor (Ecor = 0.083 ± 0.02 V) and corrosion current icor (icor = 0.145 ± 0.05 μA cm−2) of SLM Ti–6Al–4V alloy, estimated from anodic polarization tests, are under minimum recommended values for biomaterial surgical applications. Based on open-circuit potential (OCP) investigations, one may infer that this good corrosion resistance is due to the formation of a fast and stable protective oxide layer. According to X-ray photoelectron spectroscopy (XPS) results, this protective oxide layer is mainly formed from TiO2. From electrochemical impedance spectroscopy (EIS) investigations, a slightly lower corrosion resistance was observed at SLM Ti–6Al–4V alloy compared to the wrought one. Thus, the R1 associated with barrier film resistance of SLM Ti–6Al–4V is 339.1 kΩ cm2 whereas that one of wrought Ti–6Al–4V is 780.1 kΩ cm2. These results are conspicuous ones because they point out that SLM technique, which allows obtaining easily customized implants without expensive costs, is a valid alternative for obtaining new alloys for medical applications.
      PubDate: 2022-06-01
       
  • Influences of High-Basicity High-Alumina Refining Slags on the Cleanliness
           and Control of Non-metallic Inclusions in Inconel 625 Superalloy

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      Abstract: Abstract Inconel 625 is a corrosion and oxidation-resistant nickel-based alloy with potential applications in boilers and pressure vessel. However, its corrosion resistance and mechanical properties are related to its purity. Unfortunately, fabrication of Inconel 625 alloy with high cleanliness and competitive cost remains a research and engineering challenge. With that, we report a new study on high-basicity slag-smelting technique used to improve the purity of Inconel 625. More specifically, the effect of slag basicity and reaction time on the cleanliness and the control of oxide inclusions in Inconel 625 alloy were thoroughly investigated. The results showed that slag B with higher basicity possesses stronger ability in improving cleanliness and removing inclusions. Moreover, the inclusions in Inconel 625 alloy refining using slag A mainly and consistently composed of MgO-Al2O3. In the case of refining using slag B, however, three different types of impurity inclusions were formed, including MgO, binary MgO-Al2O3, and ternary CaO-MgO-Al2O3 in the refined Inconel 625 alloy. A more detailed analysis based on thermodynamic calculations revealed that MgO-Al2O3 can be spontaneously formed in the alloys during the smelting using both slag systems. However, the content of MgO in slag B is closer to saturation, which contributed significantly to the formation of MgO-based inclusions.
      PubDate: 2022-06-01
       
  • Permanent Strength of Metals: A Case Study on FCC Metals Processed by
           Severe Plastic Deformation

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      Abstract: Abstract The present study emphasizes the importance of the direct evaluation of the athermal strength of structural materials, which is the time-independent material strength that corresponds to the basic capability to bear stresses caused by external forces permanently, and we call it the “permanent strength.” The present experimental study, taking FCC metals processed by severe plastic deformation (SPD), shows that the permanent strength is unexpectedly much lower than the flow stress temporally observed in a standard tensile test. More than half of the observed flow stress corresponds to the time-dependent thermal strength. Furthermore, the grain refinement associated with SPD processing never contributes to the augmentation of the permanent strength, i.e., the Hall–Petch relation is not applicable to as-SPDed materials. In contrast to aluminum, for copper, the low permanent strength produced by SPD is never revived by subsequent annealing. These observations elicit the general view that we should know the permanent strength of structural materials, not limited to SPD-processed metals, because we must confirm that the permanent strength is higher than the allowable stress in structural design to ensure the use of the structure within its elastic range in normal environments.
      PubDate: 2022-06-01
       
  • Segregation Neutralised Steels: Microstructural Banding Elimination from
           

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      Abstract: Abstract Banding in commercial dual-phase steels, such as banded ferrite and pearlite or ferrite and martensite microstructures, is inherited from segregation during solidification in continuously cast material, predominantly from Mn segregation, and subsequent rolling. The banded microstructures lead to anisotropic mechanical properties which is generally undesirable. This paper presents an alloy design approach (termed “segregation neutralised” steels) to remove banding of the second phase by utilising co-segregation of both austenite and ferrite stabilisers to reduce local variability in second phase stability. The new composition proposed also considers achieving the same strength levels through maintaining the same second phase fraction, grain size and solid solution strengthening increments. Phase field modelling has been used to predict the segregation and phase transformation behaviours for a commercial composition dual-phase steel and the new composition segregation neutralised steel. A 5 kg laboratory alloy production route (casting, hot rolling and coiling simulation, cold rolling and annealing) has shown that the banded structure seen in commercial dual-phase steels is accurately reproduced and that banding has been reduced dramatically in both the hot rolled condition as well as after cold rolling and annealing in the new segregation neutralised steel. Chemical analysis has shown that in the segregation neutralised alloy the second phase distribution shows no correlation to the segregation bands, due to the achieved balance in austenite and ferrite stabilisers.
      PubDate: 2022-06-01
       
  • Atomic Ordering at the Interfaces Between Liquid Aluminum and Polar AlN{0
           0 0 1} Substrates

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      Abstract: Abstract AlN particles are formed in liquid Al metals/alloys during liquid-dealing and casting. They may act as potential nucleation sites during solidification. Along its [0 0 0 1] axis, AlN consists of Al3+N3- dipolar double-atom layers in the ionic model. Thus, the AlN{0 0 0 1} substrates are terminated by either an Al3+ or a N3- layer, being polar. Here we investigate the atomic ordering at the interfaces between liquid-aluminum and AlN{0 0 0 1} using an ab initio molecular dynamics technique. We have observed a rich variety of interfacial chemistry and identified an ordered Al layer terminating the substrates. The newly formed terminating Al atoms are positively charged. The liquid Al adjacent to the interfaces exhibit strong layering but weak in-plane ordering. The obtained information helps get insight into the role of aluminum nitride as potential nucleation sites in solidification of Al-metals, and further enriches our knowledge about nucleation
      PubDate: 2022-06-01
       
 
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