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Abstract: The effect of Ge addition on the microstructure, transformation temperatures and mechanical properties of (Ni56.5Fe17Ga26.5)100−x Ge x ferromagnetic shape memory alloys was investigated. With the increase of Ge content in these alloys the martensitic transformation temperatures decrease almost linearly from higher than 100°C down to −70°C or even lower that is attributed to the change of the electron concentrations of the Ni–Fe–Ga(Ge) alloys. The addition of Ge also significantly enhances the compression strength and the ductility of the alloys. The determined relationships between transformation temperatures and the mechanical properties and the Ge content will be useful for designing a suitable Ni–Fe–Ga(Ge) alloy device with a required martensitic transformation temperature and optimized mechanical property. [Copyright &y& Elsevier]

Abstract: The effect of Ge addition on the microstructure and martensitic transformation of polycrystalline Ni56.5Fe17Ga26.5 shape memory alloy was investigated using optical metallography technique, X-ray diffraction and differential scanning calorimeter. The results showed that the martensitic transformation temperatures decrease monotonously with the increase of fraction of Ge substitution for Ni. The decrease of the transformation temperatures should be related to the change of the electron concentration after the addition of Ge in NiFeGa alloys. [Copyright &y& Elsevier]

Abstract: A systematical study of substitution of Ge for Ni, Fe, and Ga in the non-stoichiometric NiFeGa alloys was performed in this work. The effect of Ge addition on the structure and martensitic transformation in NiFeGa alloys was investigated by an optical microscope, X-ray diffraction, and differential scanning calorimeters. The results show that the transformation temperatures decrease almost linearly with increasing Ge content in all the three types from higher than 100 down to −90°C and even lower. The decreases in rate of the martensitic transformation temperatures are different for the three cases. It is large for Ni substituted by Ge, slow for Ga and intermediate for Fe. The determined relationship will be significant for designing a suitable NiFeGa alloy with a required martensitic transformation temperature for application at specific temperature. [Copyright &y& Elsevier]

A series of Al–Fe–Mo–Si alloys with and without additions of Ti and Zr for elevated temperature applications have been produced by rapid solidification. These alloys are mainly strengthened by Al12(Fe,Mo)3Si dispersoids, exhibiting superior elevated temperature strengths and better damping capacity than conventional aluminum alloys. [Copyright &y& Elsevier]

Single-crystalline Li 2 Ti 6 O 13 nanobelts have been prepared from Na 2 Ti 6 O 13 nanobelts as the precursor templates via sodium/lithium ion-exchange in molten LiNO 3 at 400 °C for 10 h for the first time. Both Na 2 Ti 6 O 13 and Li 2 Ti 6 O 13 nanobelts are also characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and high-resolution transmission electron microscopy (HRTEM). Our experiments show that Na 2 Ti 6 O 13 and Li 2 Ti 6 O 13 nanobelts exhibit higher photocatalytic efficiency than their bulk counterparts for the degradation of Rhodamine B (RhB) under ultraviolet light (UV) irradiation. In comparison to Na 2 Ti 6 O 13 nanobelts, Li 2 Ti 6 O 13 nanobelts exhibit lower photocatalytic efficiency, which may result from the expansion of tunnel space in Li 2 Ti 6 O 13 . However, the electrochemical Li insertion–extraction experiments reveal that the stable reversible discharge capacity of Li 2 Ti 6 O 13 nanobelts is higher than that of Na 2 Ti 6 O 13 nanobelts. Moreover, our results also indicate that the reversible discharge capacities of Na 2 Ti 6 O 13 and Li 2 Ti 6 O 13 nanobelts are slightly less than that of their bulk counterparts. [ABSTRACT FROM AUTHOR]

Highlights: [•] Microstructures of two Co modified NiAl coatings have been studied. [•] The addition of Co improves the corrosion resistance in sulfate salts at 700°C. [•] For the sulfide and its eutectic of Co are more stable than those of Ni. [•] In chloride salts coating with medium Co content has best corrosion resistance. [ABSTRACT FROM AUTHOR]

[Display omitted] To improve the bioactivity of titanium alloy (Ti-6Al-4V), CaO-SiO 2 coatings on titanium alloys were fabricated using laser cladding method. The effect of Na 2 O and ZnO on the microstructure and properties of the prepared coatings was discussed. The microstructure of the CaO-SiO 2 coatings consists of cellular grains and cellular dendrites. The mutual diffusion of elements occurs between the coating and substrate. The base CaO-SiO 2 coating is composed of different phases including CaTiO 3 , α-Ca 2 (SiO 4), SiO 2 , TiO 2 and CaO. The formation of CaTiO 3 in the ceramic layer was analyzed through thermodynamics. Na 2 O has little influence on the microstructure, average hardness and wear resistance. When ZnO is added to the precursor, the microstructure turns to cell dendrite, and ZnO and Zn 2 SiO 4 appear in the corresponding coating. The addition of ZnO reduces the average hardness and wear resistance of the ceramic layer. The in vitro soaking in SBF shows that the laser cladding coating has the ability to form an apatite layer. [ABSTRACT FROM AUTHOR]

• The mechanism of the apatite formation on the cladding layer is discussed. • The main phase that induces apatite formation is the compound containing Si. • The biocompatibility of the cladding layer is evaluated. • MgO refines the structure and slightly reduces the average hardness of ceramic layer. • The wear resistance of the ceramic layer decreases with the increase of MgO content. To improve the bioactivity of titanium alloy (Ti-6Al-4V), laser cladding derived CaO-SiO 2 -MgO system ceramic coatings were successfully fabricated on the surface of titanium alloy. The effect of MgO content on microstructure, mechanical and biological properties of laser cladding coatings was analyzed. The mechanism of the formation of apatite on the cladding layer in simulated body fluid (SBF) was discussed. The laser cladding derived CaO-SiO 2 ceramic layer is mainly composed of CaTiO 3 , CaO, α-Ca 2 (SiO 4), SiO 2 and TiO 2. The main phases of the ceramic layer contained different MgO content are all CaTiO 3. MgO refines the microstructure of the ceramic layer, and slightly reduces the average hardness of the ceramic layer. The wear resistance decreases with the increase of MgO content. The compounds containing Si in the cladding layer are the main components that induced apatite formation. After soaking in simulated body fluid (SBF) for 21 days, the apatite layer is formed on the coating surface. The hemolysis test, in vitro cytotoxicity test and systemic toxicity test demonstrate that the cladding coating not cause hemolysis reaction, and have no toxicity to cell and living animal, which shows the cladding coating has good biocompatibility. [ABSTRACT FROM AUTHOR]