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The effect of spraying power on the microstructure and wear resistance of Ni-10 wt. %Al coating plasma sprayed with a 500 Hz sound vibration has been investigated. With the application of sound vibration, the compactness, cohesive bonding strength, and wear resistance of the coatings are all much higher. Meanwhile, with the increase of spraying power, the enhancement degree of the compactness, cohesive bonding strength, and wear resistance of the coatings are all increased. The sound vibration effects, which contain sound pressure, acoustic streaming, and heat effect, on the molten droplets are increased for their increasing melting induced by increasing spraying power. The wetting, flowing, and solidification of the molten droplets are all affected. Better wetting and flowing of the molten droplets promote their bonding on the surface of substrates and the solidified molten droplets, and their filling in the gaps of the solidified droplets. [ABSTRACT FROM AUTHOR]

In this paper, a new nanoscale metal Ti particle-reinforced Mg-3Al-1Zn matrix composite was successfully designed and prepared, which is mainly characterized by the fact that in addition to the "light" advantages of magnesium matrix composite, it also realizes bidirectional improvement of strength and ductility of the composite, and can be used as an alternative material for military light vehicle armor and individual armor. The SEM test shows that the nano-Ti particles are uniformly distributed at the grain boundary under the extruded state, which nails the grain boundary, inhibits the grain growth, and significantly refines the grain. XRD tests show that the addition of nano-Ti particles increases the crystallinity of the composite, which is consistent with the SEM test results. In addition, the EBSD test shows that the weakening of the texture of Ti/Mg-3Al-1Zn matrix composites and the increase in the starting probability of slip system are the main reasons for the improvement in ductility. Mechanical tests show that the yield strength, tensile strength, and elongation of the 0.5 wt% Ti/Mg-3Al-1Zn matrix composites exceed the peak values of ASTM B107/B107M-13 by 38.6%, 26.7%, and 20%, respectively. [ABSTRACT FROM AUTHOR]

The copper-clad magnesium composite wire with a diameter of 3.12 mm and good interface bonding was prepared by cold rotary swaging. The effects of cold rotary swaging and annealing temperature on microstructure and properties of the wire were studied by electron backscatter diffraction, transmission electron microscopy, as well as mechanical and electrical properties tests. The results show that the multi-pass cold rotary swaging composite has a great effect on grain refinement, microstructure recovery and structural unit reorientation, and can also make the wire obtain good interfacial bonding quality, improve mechanical properties, and the tensile strength can reach 289 MPa. The width of the interface layer widened with the increase of temperature, and the increase improved significantly at annealing temperatures of 450 °C and 500 °C, and the intermetallic compounds Mg2Cu and MgCu2 were found in the longitudinal section of the wire, respectively. After a reasonable annealing process of 400 °C/1 h, the interface layer did not thicken significantly, and the ductility and conductivity of the wire were the best, and the elongation after fracture and conductivity could reach 17% and 81.1% IACS, which increased by 15.2% and 3.8% compared with before annealing, respectively. [ABSTRACT FROM AUTHOR]

In this work, an ultrafine-grained Cu-1wt.%Al2O3 composite was prepared by a high-pressure torsion (HPT) technique using Cu and nano-Al2O3 powder. The effect of temperature on the microstructures and mechanical properties was investigated. Compared with consolidation at room temperature, both the tensile strength and plasticity were improved when the Cu-1wt.%Al2O3 composite was consolidated at elevated temperature, and an amazing 1077.8±40.9 MPa tensile strength was obtained if Cu-1wt.%Al2O3 composites were first HPT consolidated at room temperature followed by consolidation at elevated temperature. [ABSTRACT FROM AUTHOR]

To meet the increasing demand and stringent requirements of automotive structural steels, intercritically annealed quenching and partitioning (QP) steels are attracting significant attention owing to their excellent strength–plasticity balance. However, to date, limited reports have focused on the correlation between the microstructure and strength of intercritically annealed QP. In this study, the mechanical behaviors of QP steels with different Si contents were investigated by developing a physical-based mechanical model based on microstructural characterizations. In situ neutron diffraction was used to analyze the evolution of the phase constitution. Si content influenced the phase transformation behavior of the test steel. In the early stages of deformation, Si-strengthened steel exhibited lower retained austenite (RA) stability and faster transformation kinetics. The variation in the RA volume fraction with the deformation was fitted using a segmented exponential function. Based on the microstructure and strengthening mechanisms, a mechanical model considering grain refinement during phase transformation was proposed. The model was validated using intercritically annealed QP steels with different Si contents. The transformation-induced plasticity effect, that is, the contribution of RA to the strength, was discussed from two perspectives. Deformation-induced martensite (DIM) exhibited a significant work-hardening rate owing to the high solid solution strengthening by carbon and the high dislocation density. The residual RA after the DIM transformation exhibited a non-negligible stress distribution. Particularly, the grain boundary density and dislocations increased with strain, strengthening the remaining RA. [ABSTRACT FROM AUTHOR]

The development of advanced high-strength steel has become the research focus of steel in order to meet low emission requirements. Different annealing temperatures from 600 °C to 900 °C were applied to 1200 MPa Grade 13Mn TRIP steels with (30B steel) or without B (0B steel). The effects of B addition on microstructure and mechanical properties with different annealing temperatures were investigated. Except for M2B in 30B steel, both steels annealed at 600 °C or 700 °C contained only austenite. When annealed at 800 °C or 900 °C, ε-martensite and α′-martensite were observed whereas 30B steel had less of them. 30B steel had higher yield strength (YS) and tensile strength (TS) regardless of the annealing temperature. Total elongation (TE) of 30B steel was smaller when annealed at 600 °C or 700 °C but larger at 800 °C or 900 °C. B addition refined austenite grains, and therefore depressed phase transformation to ε-martensite and α′-martensite during annealing. B addition enhanced YS and TS by refining grains, hindering dislocation movement and promoting phase transformation, but changed the fracture mechanism. The best TS × TE (53.62 GPa%) for 30B steel was reached when annealed at 800 °C. The more sufficiently triggered TRIP effect in high-temperature-annealed 30B steel accounts for its scarcely decreased TS and high TE. [ABSTRACT FROM AUTHOR]

We investigated the microstructure and wear performance of Ni-10wt.%Al coatings deposited by plasma spraying on a Ni-based superalloy loaded with a 100-Hz sound field. Applying the sound field greatly increased both the compactness and bonding strength of the coating. The coatings sprayed with and without a sound field both showed a lamellar structure. Electron backscattering diffraction analysis showed that the sound field helped to align the long axis of the γ-Ni grain perpendicular to the substrate rather than along the fine equiaxed crystal, as present in the coating sprayed without the sound field. Additionally, spraying with the sound field produced a γ-Ni phase with strong 〈001〉 orientation. The wear performance of the Ni-10 wt.%Al coating sprayed with the sound field was much better than that sprayed without the sound field. We attributed the microstructure transformation, preferred orientation, and performance enhancement of the coating to the application of the sound field during plasma spraying. Sound pressure and acoustic streaming enhanced the wettability of molten droplets on the substrate as well as the filling ability of molten droplets in the gaps between solidified particles. Applying the sound field enhanced the heat loss of molten droplets close to the substrate, causing a temperature gradient during solidification. • A 100 Hz sound field was loaded on substrate during Ni Al coatings plasma sprayed process. • Both the compactness and bonding strength of Ni Al coating were obviously improved. • A strong <001> orientation of γ-Ni was produced. • An alignment of the grain long axis to be perpendicular to the substrate was formed. • The wear performance of Ni-10wt.%Al coating was enhanced. [ABSTRACT FROM AUTHOR]

In this work, the micro-scale damage development and crack propagation features of TA15 titanium alloy with tri-modal microstructure consisting of equiaxed α (α p), lamellar α (α l) and β transformed matrix α (β t) were firstly investigated. On that basis, the dependences of fracture toughness of tri-modal microstructure on microstructural parameters were discussed. The results indicate that in the damage and fracture of tri-modal microstructure, voids mainly nucleate and grow up at the triple junctions and the interfaces of α p /α p , α p /β t and single-α l /β t due to the micro-scale strain incompatibility at these locations. By internal necking or local shearing connection with these voids, the main crack achieves an increment. It leads to two main categories of crack paths, i.e., the connection-type path caused by the connection behavior and the natural-extension-type path progressing through voids after the connection with voids. The connection-type path exerts greater influence on the fracture toughness than the natural-extension-type path. Moreover, as for the connection-type path, it can also be classified into two sub-categories, i.e., the internal necking connection-type path and the local shearing connection-type path. As far as the energy consumption is considered, more internal necking connection-type path is favorable for improving the fracture toughness, while more local shearing connection-type path is detrimental. Besides, the above void evolution and crack propagation behavior will affect the tortuosity of crack path to some extent, which will also change the overall energy consumption and final fracture toughness. As for the dependence of fracture toughness on microstructural parameters, it is found that with the increase of α p content, the proportion of low-energy-consumed crack paths (local shearing across α p and colony-α l) increase and the crack path tortuosity decreases, both of which reduce the energy consumption and result in the continuous reduction of fracture toughness. As the α l content increases, the disorderly distributed single-α l significantly increases at lower α l content, which improves the crack path tortuosity and energy consumption. However, at a higher level of α l content, single-α l decreases dramatically and the content of colony-α l becomes high, which reduces the crack path tortuosity and energy consumption remarkably. So, the fracture toughness first increases and then decreases with the increase of α l content. [ABSTRACT FROM AUTHOR]

The crystallographic orientation evolution and its dependence on processing parameters during the development of tri-modal microstructure of titanium alloy were studied by the thermal-mechanical processing tests and electron backscatter diffraction (EBSD) examination. It is found that the development of tri-modal microstructure undergoes two stages: firstly, bimodal microstructure consisting of equiaxed α (α p ) and transformed β matrix (β t : a mix of secondary α phase (α s ) and β phase) is formed after first-stage near-β forging; then, the tri-modal microstructure consisting of α p , lamellar α phase (α l ) and β t are obtained after the following heat treatment. The equiaxed α in final tri-modal microstructure does not follow the Burgers orientation relationship (OR) with β phase. Its crystallographic orientation is hardly influenced by the hot processing parameters. The lamellar α in tri-modal microstructure is right the undissolved secondary α of bimodal microstructure (obtained after first step) during the heating process of the second step. Both of them keep the Burgers OR with β phase, however, the dissolution of secondary α present selectivity to some extent making the variant selection degree of lamellar α greater than that of secondary α. The variant selection degree of lamellar α in tri-modal microstructure decreases with increasing the cooling rate, deformation degree and strain rate of near-β forging. The secondary α in tri-modal microstructure is precipitated from β phase and obeys the Burgers OR with β phase during the cooling process of the second step. The existing lamellar α plays a strengthening role in the variant selection during its precipitation. While the cooling rate, deformation degree and strain rate of near-β forging show limited effect on the probabilities of each type of misorientation and variant selection degree of secondary α. [ABSTRACT FROM AUTHOR]

In this work, the dependences of tri-modal microstructure parameters and corresponding nano & micro hardness on through-process processing parameters were quantitatively studied during the three-step thermo-mechanical processing of TA15 titanium alloy. It is found that the processing parameters of first step, especially for the deformation temperature and strain rate, mainly affect primary equiaxed α (α p ) through the α → β phase transformation and the competition between dynamic recovery and dynamic recrystallization. The second processing step primarily affects the content and thickness of lamellar α (α l ). In the third processing step, compared with low-temperature aging, normal annealing provides sufficient driving force for α l and secondary lamellar α (α s ) growing, which leads to thicker α l and α s . As for the nano & micro hardness, in one sample undergoing different process, transformed β matrix (β t ) is always harder than α l and α s due to the interfacial-strengthening effect. In addition, with increasing strain rate of the first step, α p becomes harder due to the constantly enhanced work hardening effect while the hardness of β t varies little because of the competition between interfacial strengthening and distribution disorder degree. However, the nano hardness of α l decreases firstly and then increases with strain rate, which presents the same trend with the micro hardness of integrated hardness at different processing conditions. [ABSTRACT FROM AUTHOR]

The deformation inhomogeneity of transitional region plays a great role in both the macro and micro forming qualities in the local loading forming. In this work, the dependence of deformation inhomogeneity of transitional region on the die parameters in the local loading forming of Ti-alloy rib-web component was studied based on finite element (FE) simulation. To evaluate the deformation inhomogeneity, an area-weighted strain inhomogeneity index was employed, which is calculated through the user subroutine of FE software (DEFORM-2D). It is found that there exist two kinds of strain concentration areas contributing to the deformation inhomogeneity of transitional region. One kind is the almost symmetric strain concentration area at the non-partitioned ribs, which is essentially related to the filling of rib. Another kind is the slant strain concentration area at the partitioned rib, which is caused by the multi-step loading during local loading forming. Besides, the effects of die parameters on the deformation inhomogeneity of transitional region were studied by the combination of orthogonal experiment design and FE simulation. The results suggest that the draft angle of the right rib is the most significant factor for both the deformation inhomogeneities of the partitioned rib region and whole transitional region. And, these two deformation inhomogeneities both decrease with the draft angle of the right rib decreasing. Furthermore, the relationship between die parameters and deformation inhomogeneity of transitional region is developed using the response surface methodology (RSM). Based on the RSM model, the die parameters were optimized to improve the deformation homogeneity of transitional region. The results will provide basis for the design of die parameters to improving the deformation and microstructure homogeneities in the isothermal local loading forming of Ti-alloy rib-web component. [ABSTRACT FROM AUTHOR]

The flow behavior and microstructure evolution of a near α titanium alloy with nonuniform microstructure during hot deformation were studied by isothermal compression test and electron backscatter diffraction technique. It is found that the nonuniform microstructure prior to deformation consists of equiaxed α, lamellar α in the colony form and β phase, and the α colony keeps the Burgers orientation relationship with β phase. The flow stress of nonuniform microstructure exhibits significant flow softening after reaching the peak stress at a low strain, which is similar to the lamellar microstructure. Nevertheless, the existence of equiaxed α in nonuniform microstructure makes its flow stress and softening rate be lower than the lamellar microstructure. During deformation, the lamellar α undertakes most of the deformation and turns to be rotated, bended and globularized. Moreover, these phenomena exhibit significant heterogeneity due to the orientation dependence of the deformation of lamellar α. The continuous dynamic recrystallization and bending of lamellar α lead to the “fragmentation” during globularization of lamellar α. The bending of lamellar α is speculated as a form of plastic buckling, because the bending of lamellar α almost proceed in the manner of “rigid rotation” and presents opposite bending directions for the adjacent colonies. [ABSTRACT FROM AUTHOR]

In this paper, we studied how applying a high magnetic field during solidification of Tb 0.27 Dy 0.73 Fe 1.95 alloys affected their magnetic domain structure, crystal orientation, and magnetostriction. We observed the morphology of the magnetic domain during solidification, finding it change with the applied field: from fiber like (0 T) to dot like and closure mixed (4.4 T) to fiber like (8.8 T) to fishbone like (11.5 T). The alloy solidified at 4.4 T showed the best contrast of light and dark in its domain image, widest magnetic domain, fastest magnetization, and highest magnetostriction; this alloy is followed in descending order by the alloys solidified at 11.5 T, 8.8 T, and 0 T. The orientation of the (Tb, Dy)Fe 2 phase changed with magnetic field from random (0 T) to 〈111〉 (4.4 T) to 〈113〉 (8.8 T) to 〈110〉 (11.5 T). The improvement in magnetostriction was likely caused by modification of both the magnetization process and the alloy microstructure. [ABSTRACT FROM AUTHOR]

To address the growing demand and stringent requirements for lightweight steel, quenching and partitioning (QP) steel has attracted significant attention due to its excellent strength–ductility balance. However, to date, reports on the mechanism of intercritical annealing QP have been limited. Thus, this study investigated the effect of the addition of 1.3 wt% to 2.5 wt% Si on the microstructure and mechanical properties of intercritically annealed QP steel. Neutron diffraction and quasi-in situ electron backscatter diffraction were used to analyze the deformation mechanisms of commercial-grade QP1180 steel and Si-strengthened QP steel. The microstructure of the QP steel consisted of ferrite, martensite, and retained austenite (RA). Si increased the volume fractions of ferrite and RA. The Si-strengthened QP steel with a multiphase structure, including 43% ferrite, 13% RA, and 43% martensite, exhibited better tensile strength (1330 MPa), higher elongation (21.5%), and lower yield ratio (0.615) than commercial-grade QP1180 steel. The mechanical stability of larger RA grains is lower than that of finer grains. RA experienced additional stress with the ferrite yield and Si promoted interphase deformation accommodation behavior. The interphase deformation accommodation mechanism rather than the orientation-dependent mechanism plays a key role in controlling the onset of the deformation-induced martensite (DIM) transformation. Thus, the DIM transformation was triggered before the yield of RA, and the residual RA after the DIM transformation exhibited a non-negligible stress distribution. • QP2.5Si has higher strength, better plasticity, and a lower yield ratio. • The additional lattice strain in the FCC phase promotes DIM transformation. • Residual RA after DIM transformation has a non-negligible stress distribution. [ABSTRACT FROM AUTHOR]

To control the microstructure and performance of large scale complex titanium alloy component by local loading forming, the effect of processing on microstructure in local loading forming was investigated by a through-process finite element model. It is found that the volume fraction of primary equiaxed α decreases with temperature, deformation speed and loading pass. The distribution of α fraction becomes more uniform with decreasing temperature and increasing deformation speed and loading pass. The α grain size increases with temperature and loading pass but decreases with deformation speed. The homogeneity of the grain size can be improved by increasing deformation temperature and loading pass, or decreasing loading speed. [ABSTRACT FROM AUTHOR]

Highlights: [•] Flow stress and globularization of titanium alloy with lamellar structure are molded. [•] Physically based model couples the constitutive behavior and microstructure change. [•] Globularization and Hall–Petch strengthening are considered in microstructure model. [•] The model can realize unified prediction of flow stress and globularization kinetics. [Copyright &y& Elsevier]

To improve the production process and produce high-quality annealed drawn and ironed (DI) plate, continuous annealing experiments were carried out at 620 °C, 640 °C, 680 °C, and 720 °C, and the effect of continuous annealing temperature on the microstructure, mechanical characteristics, and texture of annealed DI plate were clarified. The microstructure was tested with a scanning electron microscope (SEM); the mechanical properties and weighted average of the plastic strain ratio ( r ¯ ) were measured using a tension test; and the texture characterizations were tested by X-ray powder diffractometer (XRD) and electron backscatter diffraction (EBSD). The results reveal that, with the increase of the annealing temperature, the average grain size grew from 5.14 μm to 6.56 μm, the yield strength and tensile strength decreased, and the elongation increased. The rolling textures drastically reduced after annealing. When annealed at a lower temperature of 620 °C, the texture content of {111} <110> was the highest. When the annealing temperature increased to 640 °C, 680 °C and 720 °C, the texture content of {111} <112> was higher than that of {111} <110>. The mechanical properties of the DI plate that was annealed at 640 °C are the best, with a higher r ¯ value and a lower planar anisotropy value. [ABSTRACT FROM AUTHOR]

As a representative of the third generation of advanced high strength steel, the quenching and partitioning steel has excellent potential in automobile manufacturing. The characterization and analysis of the mechanical properties and microstructure of the quenching and partitioning steel during deformation is an effective way to explore the microstructure evolution and transformation-induced plasticity effects of complex phase steels. The relationship between the microstructure morphology and mechanical properties of a 1180 MPa-grade quenching and partitioning steel was investigated through interrupted uniaxial tensile tests plus quasi-situ electron backscatter diffraction measurements. A mixture of ferrite, martensite, and retained austenite was observed in the microstructure. It was found that the volume fraction of global retained austenite decreased linearly with the increase of displacement (0 mm–1.05 mm). The evolution of the retained austenite with typical crystal direction ranges with deformation was characterized. Results show that the orientation (111) and (311) account for the highest proportion of retained austenite grains in the undeformed sample and the mechanical stability of the (311) retained austenite grains is the best. Moreover, the retained austenite grains rotated significantly in the early stage of the specimen deformation process (around yielding), and the work hardening of the specimen was weak at this stage, simultaneously. [ABSTRACT FROM AUTHOR]

In this work, we applied sound fields with various frequencies to the plasma spraying process of Ni-10 wt.%Al alloy coatings. The effects of the sound field frequency on the microstructure, residual stress, and wear performance of the coatings were investigated. A lamellar structure was formed in the coatings sprayed with and without sound field. Both the compactness and cohesion of the coatings were enhanced by increasing the sound field frequency. Residual stress of the coatings decreased following the order of sound field frequency: 0 Hz, 100 Hz, 500 Hz, and 300 Hz. Adhesive wear was the main wear model of the coatings sprayed with and without sound field. Friction coefficient and wear rate of the sprayed coatings were both decreased with increasing sound field frequency. Enhancements of the microstructure transformation, residual stress reduction, and wear performance were all attributed to the effects of the sound field during the plasma spraying process. • Sound field with various frequencies were loaded on substrate during Ni Al coatings plasma sprayed process. • Both the compactness and bonding strength of Ni Al coating increased by increasing the sound field frequency. • Residual stress of Ni Al coating could be decreased by sound field. • The wear performance of Ni-10 wt.%Al coating was enhanced with increasing sound field frequency. [ABSTRACT FROM AUTHOR]

The power spinning of tailor-welded blank (TWB) provides a feasible way to form the large-scale curved heads of aluminum alloy. However, the inhomogeneous material property of TWB produces different and more complex spinning behaviors compared with the traditional spinning of an integral homogenous blank. In this research, the deformation characteristics, microstructure, and the properties of the power spun curved head with aluminum alloy TWB were studied. A finite element model considering the inhomogeneous material property of welded blank is developed for the analysis of the power spinning process. To conduct accurate and efficient simulation, an effective meshing method is proposed according to the feature of TWB. The simulation and experimental results show that the weld zone (WZ) presents the larger equivalent stress but smaller equivalent strain than base material zone (BMZ) in power spinning due to its larger deformation resistance. Under the combined effects of the spiral local loading path and inhomogeneous deformability of TWB, the equivalent strain near the weld zone has an asymmetric V-shaped distribution. Strain inhomogeneity gradually increases with deformation and leads to an increase of the flange swing degree. In addition, the circumferential thickness distribution is relatively uniform, which is little affected by the existence of the weld line. However, the circumferential unfitability distribution becomes non-uniform and the roundness is worsened due to the existence of the weld line. Compared to the initial blank, the microstructure in WZ and BMZ are both elongated after spinning. The tensile strength is improved but plasticity reduced after power spinning based on the circumferential and radial tests of WZ and BMZ. The results are of theoretical and technical guidance for the power spinning of the curved head component with TWB. [ABSTRACT FROM AUTHOR]

Grain-scale strain heterogeneity characteristics play a critical role in the ductile damage behavior and mechanical properties of two-phase titanium alloys. In this work, the grain-scale strain distribution, strain heterogeneity, and strain localization of titanium alloy with tri-modal microstructure (consisting of equiaxed α (αp), lamellar α (αl), and β transformed matrix (βt)) during tensile deformation were experimentally investigated. The results show that the strain probability distribution of the whole microstructure obeys normal distribution during deformation. Significant strain heterogeneities exist in each constituent (αp, αl, and βt) and the whole microstructure. At lower macro-strain, αp and αl exhibit higher average strain than those of βt and the whole of the microstructure. Meanwhile, strain heterogeneity of each constituent is small and has a negligible change. The strain heterogeneity of the whole microstructure is mainly determined by αp. At larger macro-strain, some highly deformed regions produce and their positions do not change during further deformation. As a result, the strain heterogeneity of each constituent increases fast, and the strain heterogeneity of whole microstructure is mainly related to αl in this deformation stage. On the other hand, two types of strain localization may be generated within αp and αl and at the αp/βt and αl/βt boundaries, respectively. The former type is caused by transgranular intense slip deformation and presents crystal orientation dependence. The latter type is related to the boundary sliding and presents spatial distribution dependence for αl. These strain localizations greatly determine the micro-damages, thus forming the corresponding micro-voids within αp and αl and the micro-cracks at αp/βt and αl/βt boundaries in tri-modal microstructure at larger deformation. [ABSTRACT FROM AUTHOR]

It is a challenge to enhance both strength and ductility for the Mg matrix composites. In the present work, nanostructured Mo-reinforced AZ31 composites are synthesized via powder metallurgy method. The addition of nano-sized Mo particles reduces the grain size and decreases the texture strength of the composites. The Al 5 Mo and Al 8 Mo 3 phases are formed through Al atoms diffusion and interaction with Mo atoms. The synergistically reinforcing effect of Al 5 Mo, Al 8 Mo 3 and nano-sized Mo particles improves the mechanical properties of the composites. The nano-Mo/AZ31 composite with 1.0 wt% Mo addition exhibits superior mechanical properties, with yield strength, ultimate tensile strength, and elongation of 221 MPa, 328 MPa and 12.4 %, respectively. These results mean the improvements of 20.1 %, 17.1 % and 21.6 % compared to the AZ31 Mg alloy. The strength enhancement is attributed to the grain refinement and Orowan strengthening, while the improvement in ductility is attributed to grain size reduction, texture weakening, and the activation of a broader range of slip systems. [ABSTRACT FROM AUTHOR]

Al x CoCrFeNi high entropy alloy with various Al contents has been successfully joined to 316L steel. The effect of mechanical properties of Al x CoCrFeNi induced by Al content on the interfacial microstructure in the 316L/ Al x CoCrFeNi has been investigated. All the 316L/Al x CoCrFeNi composite plates showed the typical interfacial microstructure of the high-velocity impact welding—periodic wavy interface. Four areas of the straight smooth area, the small wave area, the wave area, and the large wave area were along the radial direction in the interface orderly. The differences in wavelength, amplitude, ratios of the length in each area to the overall length, and the evolution of interfacial microstructure were discussed. The analysis of grain orientation, grain boundary, recrystallization, and orientation difference in the wave area showed that interfacial differences were caused by the difference in deformation mechanism of Al x CoCrFeNi matrix with different Al content. The deformation mechanism was closely related to the elongation and hardness in the macroscopic mechanical properties, which represented the ability to deformation and resist deformation, respectively. Consequently, the effect of Al content on the evolution of interface morphology was essentially the effect of hardness and elongation of Al x CoCrFeNi matrix. Additionally, all the wavy interfaces of 316L/Al x CoCrFeNi had good bonding strength in the wave area. • Al x CoCrFeNi HEAs with various Al contents were successfully joined to 316L steel by high-speed impact welding. • Interfaces of 316L/Al x CoCrFeNi consisted of smooth area, small wave area, wave area, and large wave area continuously. • The effect of Al content on the evolution of interface morphology was essentially the effect of hardness and elongation. • All the interfaces of 316L/Al x CoCrFeNi showed good bonding strength in the wavy area. [ABSTRACT FROM AUTHOR]

Highlights: [•] We present the change of the crystal orientation and magnetostriction of TbFe2 based alloy during treatment in the semi-solid state in high magnetic fields. [•] Orientation of the TbFe2 phase undergoes a transformation of 〈113〉 to 〈111〉 to 〈110〉 with increasing magnetic flux density. [•] Magnetostrictive property is slightly lowered at 4.4T, but strongly enhanced at 8.8T and 11.5T. [ABSTRACT FROM AUTHOR]