Two transformation-induced plasticity (TRIP) assisted duplex stainless steels, with three different stabilities of the austenite phase, were investigated by synchrotron X-ray diffraction characterization during in situ uniaxial tensile loading. The micromechanics and the deformation-induced martensitic transformation (DIMT) in the bulk of the steels were investigated in situ. Furthermore, scanning electron microscopy supplemented the in situ analysis by providing information about the microstructure of annealed and deformed specimens. The dependence of deformation structure on austenite stability is similar to that of single-phase austenitic steels where shear bands and bcc-martensite (α') are generally observed, and blocky α' is only frequent when the austenite stability is low. These microstructural features, i.e. defect structure and deformation-induced martensite, are correlated with the micro-and macro-mechanics of the steels with elastoplastic load transfer from the weaker phases to the stronger α', in particular this occurs close to the point of maximum rate of α' formation. A clear strain-hardening effect from α' is seen in the most unstable austenite leading to a pronounced TRIP effect.

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Inspired by the effect of angle between feather shaft and the feather vane on strength enhancement of feather structure, carbon fiber reinforced epoxy resin composites with eagle feather structure were prepared successfully. Based on liquid-phase oxidation, wettability of carbon fiber was improved, which enhanced bonding strength between reinforcement and matrix and built material base for mechanical strength of bionic composite. With the increase of carbon fiber content (0.1 wt.%, 0.2 wt.%, 0.3 wt.% and 0.4 wt.%), tensile strength and impact toughness of carbon fiber reinforced epoxy resin composites increased first and then decreased. Composites with 0.2 wt.% carbon fiber exhibited optimal mechanical properties, which was used for preparation of bionic composite. Compared with carbon fiber reinforced epoxy resin composite with the traditional vertically arranged structure, the composite material with the bionic structure owned higher tensile strength and impact toughness. The fracture and drawing out of carbon fiber and crack deflection were mechanical mechanism of bionic composite, which provided a new design and preparation method for carbon fiber reinforced epoxy resin composite.

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