A method has been developed that allows measurement of stress-strain curves for sheet metal being deformed in multiaxial tension. The strain state is imposed using a modification of the Marciniak in-plane biaxial stretching test. Resulting stresses are measured using a modified Xray diffraction (XRD) residual stress measurement system. This system is flexible enough to allow spatial mapping of in-plane stress and measurement of stresses at specific locations of interest on the sample, such as developing localizations. Results are presented correlating measurements on a thin strip of AA5182 with data from standard uniaxial tension test. Also presented are experimentally determined curves for this material in balanced biaxial tension in both the rolling and transverse directions.

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Self-assembled InAs quantum dots (QDs), which have long hole-spin coherence times and are amenable to optical control schemes, have long been explored as building blocks for qubit architectures. One such design consists of vertically stacking two QDs to create a quantum dot molecule (QDM) and using the spin-mixing properties of "molecule-like" coupled hole states for all-optical qubit manipulation. In this paper, the first of two papers, we introduce the incorporation of dilute GaBixAs1−x alloys in the barrier region between the two dots. GaBixAs1−x is expected to increase the spin-mixing of the molecular states needed for qubit operations by raising the barrier valence band edge and spin-orbit splitting. Using an atomistic tight-binding model, we compute the properties of GaBixAs1−x and the modification of hole states that arise when the alloy is used in the barrier of an InAs QDM. An atomistic treatment is necessary to correctly capture non-traditional alloy effects such as the band-anticrossing valence band. It also allows for the study of configurational variances and clustering effects of the alloy. We find that in InAs QDMs with a GaBiAs interdot barrier, electron states are not strongly affected by the inclusion of Bi. However, hole states are much more sensitive to the presence and configuration of Bi in the barriers. By independently studying the alloy-induced strain and electronic scattering off Bi and As orbitals, we conclude that an initial increase in QDM hole state energy at low Bi concentration is caused by the alloy-induced strain. We further find that the decrease in QDM hole energy at higher Bi concentrations can only be explained when both alloy strain and orbital effects are considered. In our second paper, we use the understanding developed here to discuss how the alloyed barriers contribute to enhancement in hole spin-mixing and the implications for QDM qubit architectures. arXiv:1810.09483v2 [cond-mat.mes-hall]

Abstract.Titanium diaphragm discdeformation problem is researched by theoretical analysis and finite element analytical in cutting process. Titanium diaphragm disc deformation finite element analysis model is established by different ways. The influence of workpiece machining accuracy is analyzed by different clamping ways. It can provide theoretical basis for titanium alloy plate membrane equipment design.