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A combination of experimental and numerical studies was carried out to understand the microstructure and formation mechanism of kink bands in α / β two-phase titanium alloys. A deformation kink band was introduced in a Ti-9Cr alloy after uniaxial compression test. The strength changes of the α and β phases inside and outside the kink band were evaluated by nanoindentation tests. A potential hardening effect was revealed in the α phase inside the kink band, while a possible softening effect was located in the β phase at the kink boundaries. Microstructural examination of the kink band was conducted by electron backscatter diffraction measurement. The crystal rotation axis was found to be perpendicular to both the (0001) basal plane of the α phase and one of the (110) planes of the β phase. The crystallographic features were characterized by transmission electron microscopy observation, revealing a prismatic 〈 a 〉 slip that occurred during the compression to accommodate the rotations around the c-axis. Nanoindentation tests were performed on an undeformed specimen to calibrate the crystal plasticity model. A crystal plasticity finite element model was developed and {110} β -rotation-type kink bands were reproduced in the simulation and confirmed the prismatic slip activity. • During the uniaxial compression test, kink deformation was revealed in the α/β titanium two-phase alloy Ti-9Cr. • EBSD measurements, nanoindentation tests, and TEM observations were carried out on the deformed grain. • The rotation axis was found normal to the (0001) basal plane and one of the common (110) β planes. • The kink deformation was initiated by an intragranular crystal rotation accommodated by prismatic dislocations. • In the CPFEM simulation, the deformation kink bands were reproduced and confirmed the prismatic slip activity. [ABSTRACT FROM AUTHOR]

Abstract: Nickel (Ni) nanoparticles with sizes of ∼35nm were deposited on the surface of silicon nanowires (SiNWs) by electroless plating technique. The magnetic properties of Ni/SiNWs were investigated. The blocking temperature (T B ) of 370K was obtained and confirmed by field-cooled (FC) and zero-field-cooled (ZFC) plots. The M–H hysteresis loops from 5K to 400K were measured. The saturation magnetization value was ∼4.5emu/g and the coercivity was ∼375.3Oe for the loop at 5K, respectively. While for the loop at 400K, these values were of ∼2.6emu/g and ∼33.3Oe, respectively. The temperature dependence of coercivity followed by the relation H C (T)= H C0[1−(T/T B )1/2], indicating a superparamagnetic behavior. The magnetization of superparamagnetic grains in a magnetic field H was better described by Langevin function at 400K. These novel magnetic properties of Ni/SiNWs were possibly attributed to the paramagnetic defects on the surface of SiNWs. [Copyright &y& Elsevier]