Showing papers in "Acta Materialia in 2014"

TL;DR: In this article, the relationship between precipitation phenomena, grain size and mechanical behavior in a complex precipitation-strengthened alloy system, Al 7075 alloy, a commonly used aluminum alloy, was selected as a model system in the present study.

TL;DR: A series of six-component (FeCoNiCrMn)100−xAlx (x = 0−20 ǫ) high-entropy alloys was synthesized to investigate the alloying effect of Al on the structure and tensile properties as mentioned in this paper.

TL;DR: Grain boundary complexion transitions are the root cause of a wide variety of materials phenomena such as abnormal grain growth, grain boundary embrittlement and activated sintering as discussed by the authors, which have defied mechanistic explanation for years.

TL;DR: In this paper, the microstructure, phase composition and mechanical properties of the AlMo 0.5 NbTa 0.4 Hf 0.6 nbTaTiZr high-entropy alloys are reported.

TL;DR: In this paper, the results of selective laser melting (SLM) processing of in situ Ti-TiB composites from optimally milled titanium diboride (TiB 2 ) powder were presented.

TL;DR: In this paper, the authors present a simple, yet instructive and demonstrative treatment of the theory of ECC of lattice defects based on Bloch wave theory using a two-beam approach.

TL;DR: In this paper, the authors used selective laser melting (SLM) for additive manufacturing process in which functional, complex parts are produced by selectively melting consecutive layers of powder with a laser beam, which enables the exploration of a wide spectrum of possibilities in creating novel alloys or even metal-metal composites with unique microstructures.

TL;DR: In this paper, an Nb25Mo25Ta25W25 refractory high-entropy alloys (HEA) was synthesized by arc melting and well homogenized at 1800°C.

TL;DR: In this article, a high-resolution scanning electron microscopy-based damage quantification technique has been employed to identify strain regimes where damage nucleation and damage growth take place, both with and without hydrogen precharging.

TL;DR: In this paper, the influence of changes in crystallographic texture on the Hall-Petch (H-P) relationship for an Mg alloy was investigated, and the texture variations were facilitated by changing the uniaxial tensile loading orientation with respect to the normal direction of the rolled Mg plate.

TL;DR: The stacking fault and interfacial energies of three transformation-and twinning-induced plasticity steels (TRIP/TWIP) (Fe 22/25/ 28Mn-3Al-3Si wt.%) were determined by experimental and theoretical methods as mentioned in this paper.

TL;DR: In this paper, an experimental-numerical methodology is introduced to strengthen the integrated understanding of microstructure and mechanical properties of multiphase alloys, enabling joint analyses of deformation-induced evolution of the micro-structure, and the strain and stress distribution therein, down to sub-micron resolution.

TL;DR: In this paper, a multi-scale model that combines the finite element method and stochastic analysis is developed to simulate the evolution of the microstructure of an Nb-bearing nickel-based superalloy during laser additive manufacturing solidification.

TL;DR: In this article, the effects of the initial microstructure of martensite on the microstructural evolution during intercritical annealing and the tensile properties of annealed specimens were investigated for Fe-9Mn-0.05C (wt.%) steel.

TL;DR: In this article, a thermodynamic approach to the formation of solid solutions in multicomponent systems is proposed using the regular solution and computing the temperature at which the free energy hypersurface changes curvature at spinodal points.

TL;DR: In this article, nanoindentation and uniaxial compression of focused ion beam-milled cylindrical micropillars (1-2 μm diameter) were conducted on as-received and pre-strained specimens.

TL;DR: The interaction between slip bands and grain boundaries in commercial-purity titanium was examined using cross-correlation-based electron backscatter diffraction in this article, where three types of interactions were observed: blocked slip band with stress concentration, slip transfer, and no stress concentration.

TL;DR: In this article, extensive molecular dynamics simulations were carried out to monitor the development of icosahedral order in Cu64Zr34 liquid and metallic glass (MG), and the results for this model liquid/glass address five questions regarding the ordering of Cu-centered coordination polyhedral towards full icosahedra, including: (i) its evolution and extent during prolonged structural relaxation; (ii) the resulting reduction in potential energy and slowing-down of dynamics; (iii) the accompanying preference of a particular type of Zr-centered Kasper coordination polyhedra; and

TL;DR: In this article, the influence of various fillers on the physical properties of triple and multifilled n-type skutterudites with the nominal composition (R 0.33 Ba 0.50 ) 0.35 Co 4 Sb 12.3 ) was investigated.

TL;DR: In this paper, the I1 intrinsic stacking fault energy (I1 SFE) is used as an alloy design parameter for ductilizing Mg alloys, and the effect of this effect on ductility of Mg15X solid-solution crystals is investigated.

TL;DR: In this article, the formation process of the bainitic microstructure as well as martensite and retained austenite was revealed by conducting dilatometry, X-ray diffraction, scanning electron microscopy, electron backscatter diffraction and transmission electron microscope (TEM).

TL;DR: In this article, the authors studied twin-twin interactions by combining experimental observations and theoretical analysis, and classified twin-two interactions into Type I and Type II for two twin variants sharing the same zone axis and two twins with different zone axes, respectively.

TL;DR: In this paper, the structural water molecules are distributed in the interlayer region and determine the mechanical performance of C-S-H gel, which can greatly weaken the stiffness and cohesive force by replacing the ionic-covalent bond with unstable H-bond connections.

TL;DR: In this paper, a model of the TRIP-maraging steel microstructure was designed with support from diffusion simulations (using DICTRA software) to investigate size effects on cRN transformation independent of other factors that can influence austenite stability.

TL;DR: In this article, two Mg alloys, Mg −1Zn−1Ce and Mg−1Zr−0.6Zr, were subjected to large strain hot rolling treatment, followed by annealing at different temperatures.

TL;DR: In this paper, a detailed study of deformation-induced segregation and precipitation mechanisms in an aluminum alloy containing 5.8% Mg subjected to severe plastic deformation (SPD) is presented.

TL;DR: In this article, the time-resolved strain and temperature profiles of magnetron-sputtered pseudoelastic TiNi films of 20μm thickness were investigated during tensile stress cycling for different strain rates.

TL;DR: In this article, the authors present and justify a concise hypothesis on the topography of the functional space of interface energies and, based on this hypothesis, construct a closed-form function that quantitatively describes energy variations in the 5-space of macroscopic parameters defining grain boundary geometry.

TL;DR: In this paper, a cost-effective aluminum alloys for high-temperature applications, using micro-hardness, electrical conductivity and atom-probe tomography measurements, were studied.