We identify the role of deformation twinning and twin–twin intersections on the strain hardening behavior of Hadfield steel single crystals using strain field measurements. In situ and ex situ strain field measurements resolved at micrometer length scales are obtained using digital image correlation. Ex situ measurements reveal that macroscopic twin-bands, which are composed of a mixture of fin...

An experimental test was carried out to explosively clad solution annealed Inconel 718 superalloy on quench-tempered AISI H13 hot tool steel. A wavy with vortices interface geometry was obtained from this experiment. A gradual change in the wavelength along the direction of welding was observed which was due to a change in the impact angle, following the plate contacts. In this paper, the exper...

The roles of grain boundaries and twin boundaries in mechanical properties are well understood for metals and alloys. However, for covalent solids, their roles in deformation response to applied stress are not established. Here we characterize the nanotwins in boron suboxide (B6O) with twin boundaries along the {0111} planes using both scanning transmission electron microscopy and quantum mecha...

in order to investigate deformation history preserved in the calcite twins in the hinterland of zagros, several samples have been collected from calcschists of the paleozoic sargaz complex in the faryab area, se iran. these samples are related to f1-recumbent folding and thrust shear zones. the twin width is about 1 and 3.8 µm (thin-twin regime); the twin strain amounts 5 and 10%; twin intensit...

In order to investigate deformation history preserved in the calcite twins in the hinterland of Zagros, several samples have been collected from calcschists of the Paleozoic Sargaz complex in the Faryab area, SE Iran. These samples are related to F1-recumbent folding and thrust shear zones. The twin width is about 1 and 3.8 µm (thin-twin regime); the twin strain amounts 5 and 10%; twin intensit...

Evaluation of the interaction between a new and the existing underground structures is one of the important problems in urban tunneling. In this work, using FLAC3D, four numerical models of single- and twin-tube tunnels in urban areas are developed, where the horizontal distance between the single- and twin-tube tunnels are varied. The aim is to analyze the effects of the horizontal dista...

Nanocrystalline (nc) materials can be defined as solids with grain sizes in the range of 1–100 nm. Contrary to coarse-grained metals, which become more difficult to twin with decreasing grain size, nanocrystalline face-centered-cubic (fcc) metals become easier to twin with decreasing grain size, reaching a maximum twinning probability, and then become more difficult to twin when the grain size ...

Combinations of high strength and ductility are hard to attain in metals. Exceptions include materials exhibiting twinning-induced plasticity. To understand how the strength-ductility trade-off can be defeated, we apply in situ, and aberration-corrected scanning, transmission electron microscopy to examine deformation mechanisms in the medium-entropy alloy CrCoNi that exhibits one of the highes...

We give error estimates for the approximation of a laminated microstructure which minimizes the energy R (rv(x))dx for a rotationally invariant, double well energy density (A). We present error estimates for the convergence of the deformation in L; the convergence of directional derivatives of the deformation in the \twin planes," the weak convergence of the deformation gradient, the convergenc...

Anisotropic plastic deformation in columnar-grained copper in which preferentially oriented nanoscale twins are embedded is studied by experimental testing, crystal plasticity modeling and molecular dynamics simulations. The dominant deformation mechanism can be effectively switched among three dislocation modes, namely dislocation glide in between the twins, dislocation transfer across twin bo...