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The AlN/Y nanocomposite and nanomultilayered films with different Y contents were fabricated by the magnetron sputtering technique. The microstructures and mechanical properties of the AlN/Y nanocomposite and nanomultilayered films were characterized and measured, respectively. The AlN/Y nanocomposite film is composed of equiaxed AlN nanocrystallites encapsulated by the Y interfaces. When the Y:Al ratio is 2:23, Y interfaces can exist as the crystallized state and keep the epitaxial growth with the adjacent AlN nanocrystallites. Accordingly, the crystallization degree and mechanical properties are improved. The AlN/Y nanomultilayered film consists of the evident multilayered structure with distinct interfaces. When the Y-layer thickness is no more than 0.7 nm, Y layers are inclined to grow epitaxially with the adjacent AlN layers, leading to the improvement of crystallization degrees and mechanical properties. The interfacial evolutions and mechanical properties variations between AlN/Y nanocomposite and nanomultilayered films have the common feature as the Y content grows. It has been experimentally and theoretically verified that the AlN/Y nanocomposite and nanomultilayered films have the same coherent-interface strengthening mechanism. [ABSTRACT FROM AUTHOR]

Highlights: [•] The non-equilibrium microstructures of Fe40Ni40B20 alloy were obtained. [•] The duplex structure were obtained by futher heat treatment. [•] The mechanical properties of the samples with duplex structure were largely enhanced. [•] We provide an effective method to improve the properties of eutectic alloy. [Copyright &y& Elsevier]

The microstructure and properties of Cu-0.42Cr (wt.%) and Cu-0.45Cr-0.14Ti (wt.%) alloy subjected to cold rolling and aging treatment are investigated through tensile testing, electrical conductivity measurement, scanning electron microscopy, and transmission electron microscopy. Results show that the tensile strength of Cu-0.45Cr-0.14Ti (wt.%) alloy enhances as the degree of deformation increases, but the degree of deformation slightly influences electrical conductivity. When deformation is changed, electrical conductivity is basically unchanged. The good combination of strength and electrical conductivity, which reach 610 MPa and 55.4% IACS, respectively, can be obtained in the Cu-0.45Cr-0.14Ti (wt.%) alloy after 80% cold rolling and aging at 450 °C for 15 min. Ti inhibits the growth of the Cr precipitation phase and enhances the precipitation strengthening effect. Ti mainly exists in the matrix in the form of solute atoms, which do not form a separate lattice structure after aging treatment. • The alloy material is prepared by a process method combining solid solution aging treatment and deformation treatment. • Ti element enhances the effect of age hardening and significantly improves the mechanical properties of the alloy. • Titanium atoms segregate around the Cr phase to slow down the rate of precipitation coarsening. • Ti atoms have never formed a separate lattice structure in the Cu-0.45Cr-0.14Ti (wt.%) alloy. [ABSTRACT FROM AUTHOR]

This paper aims to investigate the effects of stress aging treatment on the microstructure, mechanical properties and corrosion behavior of Al-Zn-Mg-Cu alloy. The alloys were subjected to SAT and stress-free aging treatment (SFAT) at 175 °C under different aging stress and aging time conditions. Various analytical techniques, including scanning electron microscopy (SEM), electron back-scatter diffraction (EBSD), transmission electron microscopy (TEM), slow strain rate tensile, X-ray Diffraction (XRD) and potentiodynamic polarization, were employed to obtain results. The findings demonstrate heightened strength, improved corrosion resistance under SAT conditions in contrast to SFAT. The alloys subjected to SAT exhibit higher strength compared to SFAT, attributed to the diffusion of stress-induced dislocations and extensive nucleation of matrix precipitates. Furthermore, the presence of large-sized and discontinuous grain boundary precipitates impedes the anodic dissolution of grain boundaries and the expansion of stress corrosion, contributing to the enhanced corrosion resistance of the alloy. • The strength of the alloys showed an increasing and then decreasing trend with increasing applied stress, the correct application of SAT can improve the strength of alloys. • SAT results in lower I corr values compared to SFAT. S100 exhibits a larger capacitance arc in the Nyquist plots, indicative of superior corrosion resistance. • SAT improves the mechanical properties of the alloy. Applied stress facilitates dislocation diffusion and aggregation, creating additional nucleation sites that promote the nucleation and growth of precipitated phases. • SAT improves the corrosion resistance of the alloy. Applying aging stress beyond a specific threshold and extending the aging time both facilitated Gbps growth and widened the PFZ. Thereby enhancing the alloy's corrosion resistance. [ABSTRACT FROM AUTHOR]

ZrN and TiNiN nanolayers are alternately deposited on silicon substrate by magnetron sputtering. A series of ZrN/TiNiN nano-multilayer films with different Ni contents are prepared by varying the Ni:Ti volume ratio of the targets. The effects of Ni content on the microstructures and mechanical properties of ZrN/TiNiN nano-multilayer films are studied by X-ray diffractometer (XRD), scanning electron microscopy (SEM), high resolution transmission electron microscopy (HRTEM) and nanoindentation instrument. The results show that with the increase of Ni content, the crystallization degree of ZrN phase first increases and then decreases. Besides, the hardness, elastic modulus and toughness of the films also increase first and then decrease with Ni content increasing. When Ni:Ti= 1:24, the ZrN/TiNiN nano-multilayer films obtain the highest hardness, elastic modulus and fracture toughness, which are 23.2 GPa, 317.8 GPa and 2.29 MPa·m1/2, respectively. This is mainly attributed to the best columnar crystal growth of the ZrN/TiNiN nano-multilayer film. The TiNiN layer changes into face centered cubic structure under the template of ZrN layer, and grows in coherent epitaxy with ZrN layer. ● A series of ZrN/TiNiN nano-multilayer films with different Ni contents are prepared by magnetron sputtering. ● When Ni:Ti= 1:24, the ZrN/TiNiN nano-multilayer films simultaneously obtain the highest hardness and fracture toughness. ● The high hardness and toughness are due to that the TiNiN layer grows in coherent epitaxy under the ZrN layer template. [ABSTRACT FROM AUTHOR]

In this work, Ti matrix composite reinforced with 5 vol % TiC ceramic was prepared using in situ technologies, then various microstructures of the composite were obtained after it was treated with thermo-mechanical treatments applied in different temperature ranges with different deformation amplitudes. Widmanstatten, bimodal or fined α laths microstructure was obtained after it was treated by thermo-mechanical treatment performed in β phase field, in α+β phase field or in upper α phase field, respectively. The measured β transfuse temperature of the composite rises about 100 K compared to that of the monolithic matrix alloy, which resulted from the carbon solid solution of the matrix. The results of tensile tests showed that the composite strength was increased after the thermo-mechanical treatment, and the increase may be attributed to the effects of the load transfer from matrix to TiC particles and the refinement of the matrix microstructure. The TEM observation shows that the size of α colonies takes an important role to the equivalent grain size of the matrix, but the size of the thickness of α plates has minor effect on it. [ABSTRACT FROM AUTHOR]

A series of TiN/Ni nanocomposite films with different Ni content were synthesized by reactive magnetron sputtering. The microstructural evolution, mechanical properties and strengthening mechanism of TiN/Ni nanocomposite film were studied. When Ni:Ti ratio is less than 1:24, the small amount of Ni can be dissolved in the TiN matrix, leading to the slight decrease of the hardness and elastic modulus. When Ni:Ti ratio rises to 4:21, Ni inclines to separate from TiN due to the thermodynamic incompatibility as an interfacial phase and grow coherently with adjacent TiN crystallites. As a result, the TiN/Ni film was remarkably strengthened with the maximal hardness and elastic modulus of 33.3 GPa and 373 GPa. As Ni:Ti ratio further increases to 5:20, Ni interface transforms into amorphous state, leading to the destruction of the epitaxial growth structure and the rapid decrease of hardness and elastic modulus. The strengthening effect of TiN/Ni nanocomposite film can be attributed to the coherent interface between Ni interfacial layers and TiN crystallites. [ABSTRACT FROM AUTHOR]

Through introducing the CrAlSiN modulation layers consisted of CrAlN and SiN x phases, a series of TiN/CrAlSiN nanomultilayered films with different Si content were synthesized by reactive magnetron sputtering. The effect of Si content on microstructural evolution and superhardness effect of TiN/CrAlSiN nanomultilayered film was investigated by XRD, HRTEM and nanoindentation techniques. When inserted by CrAlSiN nano-layers with Si:CrAl ratio less than 4:21, TiN layers can force CrAlSiN layers to transform into fcc structure and grow epitaxially with them, leading to appearance of the superhardness effect. The columnar crystal structure of TiN/CrAlSiN nanomultilayered film can be effectively refined by insertion of the CrAlSiN layers due to thermodynamic incompatibility of CrAlN and SiN x . As the Si content further increases, the amount of amorphous SiN x phase increases, which makes the CrAlSiN layers present amorphous feature and blocks the epitaxial growth structure within the TiN/CrAlSiN nanomultilayered film, resulting in the decrease of hardness and elastic modulus. [ABSTRACT FROM AUTHOR]

The NiCr/Al nanomultilayered films with different Al thicknesses (t Al) were prepared by magnetron sputtering. The structural evolution of the Al nanolayer with the increase in t Al was investigated. When the Al layer thickness changed from 1.2 nm to 2.4 nm, the Al layer could keep the co-epitaxial growth with the adjacent NiCr layer. Accordingly, the crystallization degree improved. When the Al layer thickness changed from 2.4 nm to 3.0 nm, the transformation from the coherent to incoherent interfaces took place between the NiCr and Al layers. Meanwhile, the co-epitaxial growth with the adjacent NiCr nanocrystallites was destroyed, the crystallinity and the grain size decreased, leading to the increase of the resistivity under the combined effects of the grain boundary scattering and interface scattering. The interfacial evolution of NiCr/Al nanomultilayered films was closely related to the changes of electrical properties. When the Al layer thickness changed from 3.0 nm to 3.6 nm, the surface quality of the film was improved, which effectively reduced the scattering of defects and vacancies during the electron transport, resulting in the decrease of the resistivity of the NiCr/Al nanomultilayered film. [Display omitted] • Al films inserted NiCr nanolayers with different thickness were synthesized. • The microstructure structure of NiCr was damaged with insertion of Al nanolayers. • The resistivity was renewedly increased with the change of interface structure. • The resistivity later deteriorates with the improvement of the surface quality. [ABSTRACT FROM AUTHOR]

The (AlCrTiZrHf)N high-entropy alloy nitride films were synthesized by reactive magnetron sputtering. The effects of different N 2 flow rates on the microstructures and mechanical properties of (AlCrTiZrHf)N films were studied by the X-ray diffraction (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), nanoindentation, coating friction and wear tester. The results show that the AlCrTiZrHf high-entropy alloy film presents an amorphous state. With the increase of the N 2 flow rate, the (AlCrTiZrHf)N high-entropy alloy nitride films transform to a face-centered-cubic (FCC) structure. When the N 2 :Ar ratio is 5:4, the hardness and elastic modulus of the films reach 33.1 GPa and 347.3 GPa, respectively. The strengthening effect is mainly attributed to the formation of saturated metal-nitride phases and the solid-solution strengthening of various elements. Meanwhile, the (AlCrTiZrHf)N film exhibits the low friction coefficient and superior wear resistance. Based on the excellent properties of high-entropy alloy nitride films, the (AlCrTiZrHf)N film presents a potential application in protective coating. Image 1 • The (AlCrTiZrHf)N high-entropy alloy nitride films with different nitrogen content were produced. • The (AlCrTiZrHf)N films transform to a face-centered-cubic (FCC) structure with the increase of the N 2 flow rate. • When the N 2 :Ar ratio is 5:4, the hardness and elastic modulus of the film reach the maximum of 33.1 GPa and 347. • GPa.4.The friction coefficient was 0.5. [ABSTRACT FROM AUTHOR]