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Exploring novel materials with large magnetocaloric effect and excellent mechanical properties near room temperature (RT) are highly desired for Ni-Mn based Heusler alloys. In this work, the martensitic transformation, magnetic properties, and mechanical properties of Ni50-xCoxMn50-yTiy (x = 13–15, y = 13–16) alloys were systematically investigated by tuning Co or Ti contents. The magnetism of austenite was enhanced with an increase in Co or Ti content. 5M and 6M martensites were observed in Ni-Co-Mn-Ti alloys by transmission electron microscopy. The Ni36Co14Mn35Ti15 alloy with a large magnetocaloric effect was found near room temperature by tuning composition. The largest magnetization change (ΔM) and magnetic entropy change (ΔSm) in the Ni36Co14Mn35Ti15 non-textured polycrystalline alloy obtained during martensitic transformation under the magnetic field of 5 T were about 106 emu/g and 19.3 J kg−1 K−1, respectively. Furthermore, the maximum compressive strength and ductility for the Ni36Co14Mn35Ti15 as-cast alloy can exceed 1220 MPa and 15%, respectively. The fracture mechanism and bonding interaction were analyzed by a scanning electron microscope and first-principles calculations. [ABSTRACT FROM AUTHOR]

Tensile ductility of the Ti-based composites, which consist of a β-Ti phase surrounded by ultrafine structured intermetallics, is tunable through the control of intermetallics. The two Ti-based alloys studied exhibit similar compressive yield strength (about 1000MPa) and strain (about 35%-40%) but show a distinct difference in their tensile plasticity. The alloy Ti71.8Nb14.1Ni7.4Al6.7 fractures at the yield stress while the alloy Ti71.8Nb14.1Co7.4Al6.7 exhibits about 4.5% of tensile plastic deformation. To clarify the effect of microstructure on the deformation behavior of these alloys, tensile tests were carried out in the scanning electron microscope. It is shown that the distribution as well as the type of intermetallics affects the tensile ductility of the alloys. [ABSTRACT FROM AUTHOR]

A facile method was utilized for the construction of the bioinspired superhydrophobic Mg–Li alloy surfaces with peonylike micronanoscale hierarchical structures. The resultant materials were characterized by scanning electron microscope, x-ray photoelectron spectroscopy, and water contact angle measurements. The obtained Mg–Li alloy surfaces presented the dramatically improved corrosion resistance and long-term stable superhydrophobic properties with a static water contact angle of about 160° and a small sliding angle of less than 5°, which may extend the practical application of Mg–Li alloys in industrial and high-technology fields. [ABSTRACT FROM AUTHOR]