Showing papers in "Scripta Materialia in 2009"

TL;DR: In this article, an ingot metallurgy process with hot extrusion followed by aging has been used to produce an extraordinary high-strength Mg-1.8Gd−1.7Zn−0.2Zr alloy with ultimate tensile strength of 542 MPa, proof stress of 473 MPa and elongation to failure of 8.0%.

TL;DR: In this paper, the dependence of the martensite-start temperature on the austenite grain size has been investigated and a theory based on the ability to detect transformation as a function of the grain size was proposed.

TL;DR: In this article, the postweld properties of dissimilar friction stir welds of mild steel/A7075-T6 aluminum alloy were investigated and the joint strength increased with reduction in thickness of the intermetallic compound at the weld interface.

TL;DR: In this article, the authors present mechanical and microstructure results on precipitation-hardened ductile high-strength martensitic and austenitic-martensitic steels with good ductility.

TL;DR: In this article, a branched morphology of the TiB whisker was fabricated by reaction hot pressing, and the resulting TiBw/Ti-6Al-4V composite exhibits a significantly higher tensile strength than that of the monolithic Ti−6Al−4V alloy.

TL;DR: In this paper, electron channeling contrast imaging (ECCI) was used to image dislocation cells and mechanical twins under controlled diffraction conditions in a deformed Fe −22Mn −0.6C twinning-induced plasticity (TWIP) steel.

TL;DR: This experimental study and subsequent discussion advocates the absence of plasma during SPS, a remarkable method for synthesizing and consolidating a large variety of both novel and traditional materials.

TL;DR: In this paper, electron backscatter diffraction was used to investigate the microstructural evolution of nickel powder particles during the high-velocity impact in the cold spray process, and the formation of these nanometer-sized grains was interpreted in terms of dynamic recrystallization by lattice and subgrain rotation.

TL;DR: In this paper, the microstructure of the interface between Al alloy and Mg alloy joined by friction stir welding is characterized using electron microscopy, and the intermetallic compound reaction layer has a thickness of about 1μm and consists mainly of fine-grained Al12Mg17 phase.

TL;DR: The high-temperature dielectric property and evolutionary behavior of multilayer carbon nanotube/silica nanocomposite from 30 to 600°C in the range 8.2 to 12.4 GHz were investigated in this paper.

TL;DR: In this paper, the first success of obtaining Al-rich (86 at.% Al) bulk metallic glasses (BMGs), based on an alloy composition designed from the preferable internal glass structure, was reported.

TL;DR: In this paper, the atomic structures of the nucleus of a (1 0 1 ¯ 1 ] (1 ¯ 0 1 2 ) twin in Mg were studied by atomistic simulations using density function theory and an empirical potential.

TL;DR: In this article, the effects of processing conditions and material parameters on nanoscale twinning were analyzed, including fragmentation of T/M lamellae, formation of secondary twins, twin intersection and shear banding.

TL;DR: In this paper, a method to determine the orientation relationship between martensite and bainite with the parent austenite is developed based on electron backscatter diffraction analysis.

TL;DR: In this paper, the authors reported the computed strains and strain rates during friction stir welding (FSW) of AA2524 from a three-dimensional coupled viscoplastic flow and heat transfer model.

TL;DR: In this paper, a new explanation for the stress-strain behavior of austenitic TWIP steels (or other low stacking-fault alloys deforming by twinning) is presented, emphasizing the key contribution of the reinforcement of the thin (nanometric) deformation twins both to the macroscopic strain hardening and to the development of forward and backward internal stresses in respectively twin and matrix regions.

TL;DR: In this paper, the torque, power requirement and stir zone geometry during friction stir welding of AA2524 aluminum alloy were modeled by solving the equations of conservation of mass, momentum and energy.

TL;DR: In this paper, a new severe plastic deformation (SPD) process is proposed that is suitable for deforming cylindrical tubes to extremely large strains without changing their dimensions, which can be used for future industrial applications.

TL;DR: In this article, the long-period 14H structure was characterized using atomic-resolution high-angle annular dark-field scanning transmission electron microscopy (ANNEM) and the relationship between this structural unit and other long period structures such as 18R was discussed.

TL;DR: Zhang et al. as mentioned in this paper proposed a Chinese Academics, Inst Met Res, Shenyang National Lab Mat Sci, 72 Wenhua Rd., Shenyang 110016, Peoples R China.

TL;DR: The deformation-induced martensitic transformation is believed to cause the strong work hardening and contribute to the large compressive deformability with plastic strains up to 15%.

TL;DR: The quenching and partitioning (QP) extension of this methodology to include carbon partitioning kinetics is developed in this paper, where the final austenite fraction is less sensitive to quench temperature than previously predicted, in agreement with experimental results.

TL;DR: In this article, the Mg-6Al-1Zn magnesium alloy sheets were rolled at high temperatures of 723-793 K using differential speed rolling and the Erichsen value remarkably increases about 1.5 times due to the weakened basal texture regardless of the coarser grains with increasing the rolling temperature from 723 to 793 K.

TL;DR: In this article, uniaxial compression experiments on 3 mu m diameter micropillars of a Zr-based bulk metallic glass in as-cast, shot-peened and structurally relaxed conditions were conducted.

TL;DR: In this paper, a novel method of fabricating age-hardenable magnesium alloys with high strength and high ductility was developed using high-ratio differential speed rolling combined with low-temperature aging.

TL;DR: In this paper, a slip-independent and slip-assisted twin growth mechanism for hexagonal close-packed (hcp) metals was proposed. But the model was applied to Mg single crystals and the results showed that twin thickening proceeds independently of slip.

TL;DR: In this paper, a linear relationship between stretch formability and the work-hardening capacity was shown, represented by the inverse of the yield ratio, and the randomization of texture and the increase in grain size increased the workhardening exponent.

TL;DR: In this article, the hydrogen storage properties and structure of Mg3Pr and Mg-3PrNi0.1 alloys were investigated by X-ray diffraction and pressure-composition-isotherm measurement.

TL;DR: The mechanical properties of several B-free and B-doped Co-Al-W superalloys with different volume fractions of the Co3(Al,W)-γ′ phase were examined by mechanical tests at various temperatures up to 980°C as mentioned in this paper.

TL;DR: In this paper, the authors show that the yield strength of sub-micron single-crystal metal pillars and wires increases with decreasing pillar diameter, and show that σ rss / μ = A ( d / b ) m for face-centred cubic (fcc) metals.