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In the aircraft industry, the high-strength aluminum alloys AA7075 and AA2024 are extensively used for the manufacture of structural parts like stringers and skins, respectively. Additive manufacturing (AM) of the AA7075-T6 aluminum alloy via friction stir deposition to build continuously multilayered parts on a substrate of AA2024-T4 aluminum has not been attempted so far. Accordingly, the present work aimed to explore the applicability of building multilayers of AA7075-T6 alloy on a substrate sheet of AA2024-T4 alloy via the additive friction stir deposition (AFSD) technique and to optimize the deposition process parameters. The experiments were conducted over a wide range of feed rates (1–5 mm/min) and rotation speeds (200–1000 rpm). The axial deposition force and the thermal cycle were recorded. The heat input to achieve the AFSD was calculated. The AA7075 AFSD products were evaluated visually on the macroscale. The microstructures were also investigated utilizing an optical microscope and scanning electron microscope (SEM) equipped with an advanced EDS technique. As well as the presence phases, the mechanical performance of the deposited materials in terms of hardness and compressive strength was also examined. The results showed that the efficiency of the deposition process was closely related to the amount of heat generated, which was governed by the feeding rate, the rotational speed, and the downward force. AA7075 defect-free continuously multilayered parts were produced without any discontinuity defects at the interface with the substrate at deposition conditions of 1, 2, 3, and 4 mm/min and a constant 400 rpm consumable rod rotation speed (CRRS). The additively deposited AA7075-T6 layers exhibited a refined grain structure and uniformly distributed fragment precipitates compared to the base material (BM). The gain size decreased from 25 µm ± 4 for the AA7075-T6 BM to 1.75 µm ± 0.41 and 3.75 µm ± 0.78 for the AFSD materials fabricated at 1 and 4 mm/min deposition feeding rates, respectively, at 400 rpm/min. Among the feeding rates used, the 3 mm/min and 400 rpm rod rotation speed produced an AA7075 deposited part possessing the highest average hardness of 165 HV ± 5 and a compressive strength of 1320 MPa. [ABSTRACT FROM AUTHOR]

Mg-3Sn-1Mn-xLa alloy bars were prepared using backward extrusion, and the effects of the La content on the microstructures and mechanical properties of the alloy were systematically studied using an optical microscope (OM), X-ray diffraction (XRD), scanning electron microscope (SEM), transmission electron microscope (TEM), and tensile tests. The results of this research show that the Mg2Sn phases were mainly formed at the α-Mg grain boundaries and within the grains in the Mg-3Sn-1Mn alloy. After adding a certain amount of La, the plate-shaped MgSnLa compounds consisting of Mg17La2, Mg2Sn, and La5Sn3 gradually disappeared in the α-Mg matrix and grain boundaries. With an increase in La content, the Mg2Sn phase in the crystal was gradually refined and spheroidized. When the content of La reached 1.5%, the tensile strength of the alloy reached 300 Mpa and the elongation reached 12.6%, i.e., 25% and 85% increases, respectively, compared to the Mg-3Sn-1Mn alloy. The plate-shaped compound of Mg-3Sn-1Mn-1.5La had an average length of 3000 ± 50 nm, while the width was 350 ± 10 nm. Meanwhile, the extruded alloy's grain size was significantly refined, and there were many small cleavage steps and dimples in the fracture surface of the alloy. When the La content reached 2%, the alloy performance showed a downward trend due to the coarsening of the grains. The formed plate-shaped MgSnLa compounds and Mg2Sn phases were consistent with the α-Mg matrix. They effectively pinned the dislocations and grain boundaries, which is the main reason for strengthening the mechanical properties of extrusion alloys. [ABSTRACT FROM AUTHOR]

In this study, the effects of magnesium addition on the microstructure and comprehensive properties of Al-5Si-5.3Cu-0.3Sr-0.2Zr-0.2Y-0.06Ti alloys were investigated by optical microscope, scanning electron microscope, transmission electron microscope, hardness tester, and tensile testing machine. It is found that the addition of magnesium increases the number of undissolved particles in the alloy. However, on the one hand, magnesium addition refines the θ′ phase and increases its number density in the alloy. On the other hand, it generates a smaller Q′ phase. Both phases can enhance the precipitation strengthening and dislocation strengthening of the alloy. In addition, adding magnesium reduces the width of the precipitation-free zone (PFZ) and changes the distribution of grain boundary precipitates (GBPs). At 1% magnesium addition, the dislocation strengthening and precipitation strengthening effects of the θ′ and Q′ phases were the best, the width of PFZ was the smallest, and the GBPs were discontinuously arranged along the PFZ. Therefore, a high-strength, high-hardness, and intergranular corrosion-resistant cast aluminum alloy with dense structure, a tensile strength of 364.4 MPa, elongation of 4.87%, hardness of 145.4 HV, and intergranular corrosion grade of 3 was obtained. [ABSTRACT FROM AUTHOR]

In this study, the influence of the high-pressure torsion (HPT) processing parameters and solution treatment (ST) on the corrosion and tribocorrosion behavior of CoCrMo (CCM) alloys was investigated for possible usage in biomedical applications. The corrosion behavior of the CCM alloys was investigated by using potentiodynamic scanning (PDS) and electrochemical impedance spectroscopy (EIS) tests. Tribocorrosion tests were carried out in a reciprocating ball-on-plate tribometer at 1 Hz, 1 N load, and 3 mm stroke length for 2 h. All electrochemical measurements were performed using a potentiostat in standard phosphate-buffered saline (PBS) solution at body temperature (37 ± 2 °C). The samples were characterized by using a scanning electron microscope (SEM), transmission electron microscope (TEM), optical microscope (OM), and X-ray diffraction (XRD). The deepness and width of wear tracks were examined by using a profilometer. The results showed that HPT and ST processes did not affect significantly the corrosion resistance of samples. However, the ST-treated samples had a higher material loss during sliding in standard phosphate-buffered saline (PBS) at body temperature as compared to HPT-treated samples. [ABSTRACT FROM AUTHOR]

The hot deformation process significantly affects the performance of the manufactured Zr alloy components in nuclear reactors. The hot deformation behavior of the Zr-1wt.% Nb alloy with an initial β-quenched microstructure was evaluated using hot compression test at the temperature range of 600-950 °C and the strain rate range of 0.001-0.8 s−1. The constitutive equation was determined using kinetic analysis. The strong effect of Nb on decreasing self-diffusion in Zr was the reason for the obtained large activation energy of 390 kJ/mol in the Zr-1Nb alloy. Based on the dynamic material model, the processing map was constructed at the strain of 0.8 to show the stable and unstable hot deformation regions. The microstructural features of the hot deformed samples were observed using optical and scanning electron microscopes. The results indicated that the hot deformed microstructures were fully recrystallized so that the grain size of the as-received microstructure of the Zr-1Nb alloy was reduced from 1 mm to less than 4 μm after hot deformation at 800 °C. The optimum region in the hot deformation of the Zr-1Nb alloy with dynamic recrystallized microstructure and the peak efficiency of 40% was located at the temperature range of 675-775 °C and the strain rate range of 0.001-0.01 s−1. On the other hand, flow localization and macro-surface cracking occurred within the strain rate range of 0.1-0.8 s−1. [ABSTRACT FROM AUTHOR]

Cu–9Ni–6Sn alloys have received widespread attention due to their good mechanical properties and resistance to stress relaxation in the electronic and electrical industries. The hot compression deformation behaviors of the Cu–9Ni–6Sn–0.3Mn–0.2Zn alloy were investigated using the Gleeble-3500 thermal simulator at a temperature range of 700–900 °C and a strain rate range of 0.001–1 s−1. The microstructural evolution of the Cu–9Ni–6Sn alloy during hot compression was studied by means of an optical microscope and a scanning electron microscope. The constitutive equation of hot compression of the alloy was constructed by peak flow stress, and the corresponding 3D hot processing maps were plotted. The results showed that the peak flow stress decreased with the increase in the compression temperature and the decrease in the strain rate. The hot deformation activation energy was calculated as 243.67 kJ/mol by the Arrhenius equation, and the optimum deformation parameters for the alloy were 740–760 °C and 840–900 °C with a strain rate of 0.001~0.01 s−1. According to Deform-3D finite element simulation results, the distribution of the equivalent strain field in the hot deformation samples was inhomogeneous. The alloy was more sensitive to the deformation rate than to the temperature. The simulation results can provide a guideline for the optimization of the microstructure and hot deformation parameters of the Cu–9Ni–6Sn–0.3Mn–0.2Zn alloy. [ABSTRACT FROM AUTHOR]

This paper presents the new route of fabrication of H-AlSi24Cu3.8Mg0.8 alloy, assisted by ultrasonic vibration stirring and squeeze casting (UVSS). The primary objective of this investigation is to establish the tribological characteristics of the prepared aluminium alloy under dry, lubricated, and coated sliding conditions. Oil SAE20W40 is used as a lubricant and diamond-like carbon (DLC) is used as a coating. Under a load between 20 N and 50 N, a linear reciprocating tribometer (LRT) with a ball-on-plate geometry is used. Alloy was examined using an optical microscope, scanning electron microscope with EDS, 3D surface profilometer, Brinell hardness tester, and tensometer for pre- and postcharacterization of alloy, surface, and worn tracks. The DLC-coated condition yields the lowest wear and coefficient of friction. [ABSTRACT FROM AUTHOR]

Ti-6Al-4V is an α+β phase Ti alloy which is widely used because of its microstructural features. Complex three-dimensional (3-D) parts can be created directly from computer models by selectively melting (SLM) the metal powder using additive manufacturing (AM) technology. In this present work hot corrosion experiments were performed on the selective laser melted sample and as received sample in laboratory air and NaCl environment at 600°C for 50 cycles. The parabolic rate constants were calculated for different environments from the thermogravimetric data obtained for the samples and they show that corrosion rate is minimum in laboratory air and maximum for SLM sample in NaCl environment due to the presence of gaseous chlorides. The microstructure morphologies and the oxide scales formed upon hot corrosion was characterized by optical and scanning electron microscope (SEM) while the constituents were determined with energy-dispersive X-ray (EDX) analysis to understand the corrosion mechanisms. The high corrosion rate of SLM compared to the as-received sample was studied by analysing the area percentage of porosity. Since helicopters and planes are used in sea areas this work is practically important in the aeronautical field. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of stress ratio on room temperature high‐cycle fatigue life of Ti‐43.5Al‐4Nb‐1Mo‐0.1B alloy, high‐cycle fatigue life test of TNM‐TiAl alloy at stress ratio of −1, −0.5, 0.1, 0.5, 0.8, and 1 was performed on the universal testing machine. The fracture mechanism of TNM‐TiAl alloy under different stress ratios was determined by observation and analysis of microstructure and fracture surface by scanning electron microscope (SEM), energy dispersive spectroscopy (EDS), and optical microscope (OM). The results show that fatigue life of TNM‐TiAl alloy with different stress ratios is mainly affected by the mean stress and stress amplitude. The fatigue life decreases with the increase of the stress amplitude and with the decrease of the mean stress. When the stress amplitude is constant, the higher the stress ratio is, the higher the mean stress in the loading process is, the lower the fatigue life is. The sensitivity of the stress amplitude of TNM‐TiAl alloy gradually increases with the increase of the stress ratio. The different cracking mechanism and fracture mechanisms at various stress ratio are revealed. Highlights: Different stress ratios affected various fatigue fracture processes of TNM‐TiAl alloy.An equal life curve was obtained to reveal the effects of different stress ratios on TNM‐TiAl alloy.Various stress ratio affects length‐width ratio of the lamellar colonies, leading to various deformation behaviors. [ABSTRACT FROM AUTHOR]

The effects of La and Y on the microstructure and mechanical properties of cast Al-Si-Cu alloys were investigated by X-ray diffractometer (XRD), optical microscope (OM), and scanning electron microscope (SEM). The results indicated that the addition of La and Y had a great effect on the refinement of α-Al grains, the modification of eutectic Si phase, and the reduction of β-Al5FeSi length in Al-Si-Cu alloys. The A380 + 0.6 wt.% La/Y alloy exhibited the best microstructure and mechanical properties. The UTS and EI of the A380 + 0.6 wt.% La/Y alloy were 215.3 MPa and 5.1%, which were 22.9% and 37.8% higher than those of the matrix alloy, respectively. In addition, neither Al11La3 nor Al3Y generated by the addition of La and Y could not serve as the nucleation core of α-Al grains, so the grain refinement of α-Al originated from the growth limitation and constitutional supercooling. Since La and Y promote twinning generation and constitutional supercooling, the eutectic Si phase also changed from stripe-like to short fibrous or even granular and was significantly refined. Furthermore, thermodynamic calculations indicated that the Al11La3 phase was formed first and the Al3Y phase was generated on the Al11La3 phase. [ABSTRACT FROM AUTHOR]

The microstructure, tensile property and corrosion behavior of the die-casting AlSi10Cu3 alloy with 0.6 wt% (La + Yb) addition and T6 heat treatment are discussed. The results of optical microscope (OM) and scanning electron microscope (SEM) demonstrate the main phases are refined after the alloy is treated by two modification methods, and the distribution of Al2Cu phases becomes uniform after T6 heat treatment, thus increasing the ultimate tensile strength (UTS), yield strength (YS) and elongation by 21.6%, 31.4% and 52.5%, respectively. Simultaneously, the corrosion current density (iccor) reaches the minimum value of 5.89 mA·cm-2, which is reduced by 81.1%. Meanwhile, the hydrogen evolution rate and weight loss rate also reach the minimum value of 25.5 × 10-3 ml cm-2 h-1 and 116.5 μg·cm-2 h-1, and comparing with unmodified alloy, they are reduced by 54.6% and 52.2%, respectively. The optimized corrosion behavior is attributed to the refinement of the various cathode phases in the alloy. Moreover, parts of β-Al5FeSi phases are transformed into α-Al8Fe2Si phases and the uniform distribution of Al2Cu phases avoids severe local corrosion. [ABSTRACT FROM AUTHOR]

In recent years, Mg alloys have attracted increased attention for biomedical application owing to their good biodegradability, biocompatibility, and biomechanical properties. However, rapid corrosion is still one of the most common limitations for their implanted application. In this work, the microstructure and corrosion behavior of the solution- and aging-treated Mg-xGd-1Zn-0.4Zr (x = 3, 6, and 9 wt%, denoted as GZ31K, GZ61K, and GZ91K, respectively) alloys were studied using optical microscope (OM), scanning electron microscope (SEM), immersion tests, electrochemical tests, and quasi in situ corrosion method. The results show that block Gd-rich precipitates and needle-like Zr-Zn-rich precipitates are formed as well as α-Mg matrix. With the increase in Gd content, the precipitates increase and the grain size first reduces and then increases. Corrosion experiment results show that the GZ61K alloy has the best corrosion resistance and the GZ91K alloy shows the highest corrosion rate among the three alloys in simulated body fluid (SBF). It is found that α-Mg is preferentially corroded and the precipitates have better corrosion resistance as compared to the α-Mg matrix. The GZ61K alloy with the corrosion rate of 0.23 mm/y in SBF shows a promising prospect for biomedical application. [ABSTRACT FROM AUTHOR]

The main objective of this investigation is to analyze the microstructure, tensile properties, and impact toughness of Ti6Al4V alloy joints developed using optimized parameters of linear friction welding (LFW) for gas turbine blisk assembly applications. The 6 mm thick plates of Ti6Al4V alloy were joined using a friction time of 40 sec, a friction pressure of 20 MPa, a forging pressure of 10 MPa, a forging time of 3 sec, and an oscillating frequency of 14 Hz. The different regions of joints were analyzed using a stereo zoom microscope. Optical and scanning electron microscope (SEM) was used for analysing the microstructural features of joints. The room temperature tensile properties, hardness, and impact toughness of LFW-Ti6Al4V alloy joints were evaluated and correlated to the microstructural features of weld region. The fractured sections of tensile and impact toughness specimens of joints were analyzed using SEM and the failure of joints was correlated with the hardness survey. Results showed that the LFW-Ti6Al4V alloy joints developed using the optimized parameters exhibited a tensile strength (TS) of 1015 MPa, a yield strength (YS) of 940 MPa, and an elongation (EL) of 8%. The joints revealed 98.54%, 95.91%, and 66.67% of tensile strength, yield strength, and ductility of the parent metal. The LFW joints disclosed impact toughness (IT) of 17.2 J which is 89.77% impact toughness of the parent metal. The superior tensile properties and impact toughness of LFW-Ti6Al4V alloy joints are mainly attributed to a greater degree of refinement of α + β grains in the weld interface, which offers greater resistance to tensile deformation and crack propagation. [ABSTRACT FROM AUTHOR]

This study investigated the microstructure, hardness, tensile and tribological behaviour of a cooling slope Al--Si--Mg alloy following ECAP and T6 heat treatment. The optical and scanning electron microscopes were applied to investigate the microstructure of the as-cast material and heattreated ECAPed Al--Si--Mg alloy. The dry sliding wear test was tested with three different loads of 10 N, 50 N, and 100 N with constant sliding speed and sliding distance at 1.0 m/s and 9000 m, respectively, using the pin-on-disc tribometer. The hardness and tensile properties were evaluated through microhardness, UTS, and YS measurement for the as-cast Al--Si--Mg alloy, both heat-treated with and without ECAPed alloys. Moreover, wear rate and COF in the Al--Si--Mg alloy with different loads were analysed and linked with microstructural and strength behaviour after the ECAP process. Meanwhile, these analyses of results were correlated with the behaviour of the as-cast Al--Si--Mg aluminium alloy and heat-treated non-ECAPed alloy. Results demonstrated that a combination of ECAP processing and T6 heat treatment improves the mechanical behaviour, while the COF and wear rate are improved at a load of 100 N. [ABSTRACT FROM AUTHOR]

Calcium phosphate chemical conversion coatings with the additions of sodium lauryl sulfate (SLS) and dodecanesulfonic acid sodium (DSS), respectively, were prepared on the surface of the Mg-8Li alloy. The surface and cross-sectional corrosion morphologies, compositions, and corrosion behavior of the coated surfaces in 3.5 wt.% NaCl solution were respectively investigated by using a scanning electron microscope (SEM), energy dispersive spectrometer (EDS), electrochemical workstation, hydrogen evolution apparatus, and optical microscope (OM). The results demonstrated that Ca-P coatings had a petal-like structure being composed of leaf-like particles. After being respectively performed for 30 min in conversion solutions containing SLS and DSS, the corresponding average film thicknesses of surface coatings were 27 μm and 7 μm. In addition, the corrosion current densities of coated surfaces by using the conversion solutions containing SLS and DSS were 1.438 × 10−5 A·cm−2 and 4.719 × 10−5 A·cm−2, respectively. The effect of surfactants on phosphate chemical conversion coating was discussed in detail. [ABSTRACT FROM AUTHOR]

Aluminium alloys reinforced by nanoparticles are widely utilized in space vehicles, automotive components and industrial applications due to the unique characteristic of high stiffness to weight ratio. In this research, aluminium alloy 8011-TiC (Titanium Carbide) composites with a various weight percentage of reinforcement such as 5%, 7% and 9% wt.% were produced through stir casting technique. The contribution and uniform dispersion of TiC nano particles in Al 8011 was investigated through microstructural examination, mechanical and tribological behaviour. To sew up the uniform distribution of reinforcement particles over composite metal matrix alloy was investigated using Scanning and Optical Electron Microscope (OEM & SEM) depiction. The pattern of TiC content in the Al8011 alloy was observed through X-ray diffraction technique. Also, specimens are exposed to wear test as per ASTM G99 standard and the weight loss method is adopted. The result exhibits that tensile, yield strength properties and microhardness of nanocomposites particles to about increases by 35%, 170% and 150% respectively. The mechanical properties and wear resistance of 7% TiC yields better results compared with Al 8011 alloy and other compositions of augmentations. [ABSTRACT FROM AUTHOR]

The corrosion behavior and microstructure of Mg-3Zn-1Mn-xSr (x = 0, 0.5, 1.0, 1.5, 2.0 wt.%) alloys are investigated by optical microscope (OM), scanning electron microscope (SEM), electrochemical tests and immersion experiments equipped with a dynamic corrosion device. The introduction of Sr element changes the distribution of Mg7Zn3 phase in the Mg-3Zn-1Mn alloy, promoting its precipitation at the grain boundary. Decrease in grain size and second phase spacing can be observed with the increase of Sr content, and the size of semi-continuous second phases (Mg7Zn3 + Mg17Sr2) distributed along grain boundary increases. The corrosion resistance of Mg-3Zn-1Mn-xSr alloys increases with the suitable addition of Sr, but decreases with the addition of excessive Sr, indicating that the critical value exists for the addition of Sr to obtain the optimal corrosion resistance. Optimal corrosion performance (CR = 1.213 ± 0.02mm/y, Icorr = 2.80μA/cm2) of Mg-3Zn-1Mn-1Sr alloy is concluded by immersion tests and electrochemical measurements, and its corrosion morphology manifests uniform corrosion pits and dense structure due to mass accumulation of corrosion products on the damaged surface of Mg matrix. The synergistic effect of the grain size and second phase is used to explain the influence of the variation of Sr content on the corrosion performance of Mg-3Zn-1Mn-xSr alloys. [ABSTRACT FROM AUTHOR]

The effect of scandium content on the structure and properties of alloy Al – 4.5% Zn – 4.5% Mg – 1% Cu – 0.12% Zr is determined. The microstructure of the alloy is studied with identification of the phases using an optical microscope and scanning and transmission electron microscopes. The Vickers hardness and the yield strength under heating are determined. The phase diagram is plotted and the nonequilibrium crystallization is described using the Thermo-Calc software and the TTAL5 database. It is shown that addition of 0.1% scandium contributes substantially enough into the growth of the hardness after 3-h annealing at 450°C and into the yield strength after 20-h aging at 175°C. The compositions studied are recommended as a base for designing new refractory alloys based on the Al – Zn – Mg – Cu system. [ABSTRACT FROM AUTHOR]

In this study, a new alloy material Mg-Zn-Zr (ZK60) was designed for the connecting rod. It was found that the blanks sampled along the vertical direction of an extruded bar crack during the roll forging process. The microstructure and precipitates of the extruded bar were observed and analyzed using optical microscope (OM), scanning electron microscope (SEM) and x-ray diffraction (XRD). The result showed that the Zn, Zr, and MnZn2 precipitates were elongated along the extrusion direction. The mechanical anisotropy was investigated by testing the mechanical properties of the specimens sampling from different angles. Hot deformation behavior was further studied using the Gleeble 3500 thermal-mechanical simulator. The tensile and yield strengths were the highest along the extrusion direction, reaching 347 MPa and 301 MPa, respectively. The deformation resistance was also higher in the extrusion direction than that in the vertical direction. Fracture mechanisms of the sample from different directions were discussed. The ZK60 alloy was more susceptible to failure if the deformation direction was parallel to the bands of segregation area and precipitates. [ABSTRACT FROM AUTHOR]

By means of an electrochemical workstation, hydrogen evolution device, optical microscope (OM) and scanning electron microscope (SEM), the corrosion behaviors of an as-rolled Mg-8%Li alloy with a dual phase structure in 0.9 wt.% NaCl and 3.5 wt.% NaCl solutions have been investigated and compared. The results show that when the immersion time exceeds 8 h, the hydrogen evolution rate of the alloy in the 0.9 wt.% NaCl is 3 times higher than that in the 3.5 wt.% NaCl solution. Moreover, the corrosion behaviors of the alloy are obviously different in the two differently concentrated NaCl solutions. In the 3.5 wt.% NaCl solution, the localized corrosion is much more severe and can occur simultaneously in the interior of both the α-Mg and β-Li matrix phases. However, the localized corrosion in the 0.9 wt.% NaCl solution is obviously weak and mainly occurs at the α-Mg phase. [ABSTRACT FROM AUTHOR]

Solidification microstructure evolution of as-cast Al-8.8 Mg-9.2 Si, Al-12.6 Mg-7.4 Si and Al-15.4 Mg-9.8 Si with different calculated Mg2Si content in the ferrous mold were studied by optical microscope（OM）and scanning electron microscope（SEM）. The results show that the solidification path of the three alloys are L→L1+Mg2Si→L2+Mg2Si+（Al+Mg2Si）binary eutectic→Mg2Si+（Al+Mg2Si）binary eutectic+（Al+Mg2Si+Si）ternary eutectic. The solidification microstructure at room temperature is composed of a certain amount of primary Mg2Si phase, binary eutectic and ternary eutectic clusters. With increasing Si content and Mg content, the number of primary Mg2Si phase increases, its growth morphology changes from octahedral polygon to dendritic with more developed secondary dendritic walls, but the morphology of the eutectic Mg2Si phase did not change significantly. The solidification microstructure morphology of Al-12.6 Mg-7.4 Si and Al-15.4 Mg-9.8 Si alloys was compared and it was found that the cumulative value of the aspect ratio of eutectic cells decreased with the increase of Mg2Si content. [ABSTRACT FROM AUTHOR]

The laser nitriding was performed in nitrogen gas at room temperature (20 °C) and low temperature (−190 °C) by a low power fiber laser to modify the wear and abrasion resistance of NiTi alloy. The surface roughness and element composition were analyzed by roughness device and energy-dispersive X-ray spectroscopy respectively. The results of roughness show that laser treatment can change the surface roughness due to the laser remelting. The effect of laser nitriding on the microhardness, friction coefficient, and worn scars of NiTi alloy was also studied, which shows that the microhardness of the NiTi alloy increases after laser nitriding. The optical microscope and scanning electron microscope were used to characterize the surface of NiTi alloy after wear testing to observe the microstructure of worn scars. The results show that the laser nitriding with different parameters can induce a nitride layer with different thicknesses and the higher energy deposition is the key factor for the formation of the nitride layer, which can decrease the friction coefficient and reduce wear loss during the application of NiTi alloy. The improvement of wear resistance can be attributed to the hard nitriding layer. [ABSTRACT FROM AUTHOR]

Continuous research into critical functional property enhancement of materials employed in artificial intelligence systems is imperative to overcome performance limitations. This study investigated the thermal and mechanical properties of stir-cast fabricated Al-Cu alloy modified with addition of iron-millscale (IMS) particles varied from 2-6 wt.%. The alloys microstructure was analysed using both optical and scanning electron microscope coupled with energy dispersive spectroscopy (SEM/EDS). PerkinElmer Thermogravimetry/Derivative thermal analyser was used to assess the alloys thermal characteristics while the mechanical properties were evaluated using relevant state of the art equipment. Results show that the best thermal and mechanical properties comparable to established standards were achieved at 6 wt.% IMS particle addition. Contributions to the alloy enhanced performances stemmed from the structure refining propensity of IMS particles. Based on the thermal and mechanical properties demonstrated, the alloy is recommended for application in pneumatic offshore valve actuator used in oil and gas flow process lines. [ABSTRACT FROM AUTHOR]

Aluminum alloy 6061(AA6061) sheets of 4 mm in thickness are joined by laser wire-filling welding (LWFW) using the ER4047 welding wire. Microstructure and alloy element distributions near the fusion line are characterized and are investigated by optical microscope, scanning electron microscope, energy dispersive spectrometer. The results showed that the well-formed welded joints are obtained with a few thermal cracks near the fusion line. The coarse grain and a reduction in the weight ratio of magnesium to silicon can be observed, when the welding speed decreases under constant laser power. The thermal crack is caused by the decrease of the weight fraction of magnesium and the proportion of silicon content has an effect on the microhardness of welded joints. By properly controlling the welding speed, the various properties of AA6061 LWFW joints can be balanced. [ABSTRACT FROM AUTHOR]

In the present paper, the microstructure evolution of semi-solid metal slurry was investigated. The material was tested by rheocasting route. In order to better estimate the materials behavior, the investigation was performed on three series of samples. The rheocasting was conducted different stirring speed of 500, 1000 and 1500rpm and 0.3 solid fraction, before casting. The microstructure was analysed using an optical and scanning electron microscope. The results show that the relationship between the equivalent diameter of Si and α - Al particles with stirring speed can be well fitted to quadratic or linear equation. The results from this study can also be used to optimize the process and study mechanism of the rheocasting process. [ABSTRACT FROM AUTHOR]

There has been great attention on high-entropy alloys (HEAs) over the past decade. Unlike conventional alloy systems, HEAs commonly include at least five principal elements with equiatomic or near-equiatomic ratio. HEAs with their superior mechanical, magnetic, and thermal properties are promising materials for critical engineering applications. Medium-entropy alloys (MEAs), which consist of less than five principal elements, have very similar structural features with HEAs such as robust thermodynamic stability and exceptional mechanical performance. The insights of MEAs have not been fully revealed yet. In the present study, novel MEAs (Cu20Ni20Al30Ti30, Cu25Ni25Al25Ti25, Cu34Ni22Al22Ti22, and Cu35Ni25Al20Ti20) have been designed using thermo-physical calculations and Thermo-Calc software. These MEAs were then produced using copper heart arc melting and suction cast into cylindrical rods with 3 mm diameters. X-ray diffraction (XRD), optical microscope (OM), transmission electron microscope (TEM), scanning electron microscope (SEM), and energy-dispersive spectroscopy (EDS) were used for structural characterization. The corresponding results reveal that the Cu20Ni20Al30Ti30, MEA, consists of a body-centered cubic (BCC-B2) phase with intermetallic compounds (ICs), whereas Cu25Ni25Al25Ti25 has single BCC-B2 phase. When the amounts Cu and Ni are increased, system drives itself toward a face-centered cubic (FCC) structure. A dual BCC and FCC composite Cu35Ni25Al20Ti20 has been detected as the most promising MEA among the others with 820 and 1338 MPa measured yield and compressive strength, respectively. [ABSTRACT FROM AUTHOR]

Microstructure, hardness and biocorrosion properties of ZXM220–xSr alloys (x = 0, 0.2, 0.4, 0.8 and 1 wt%) were investigated, and the results were compared with each other. Microstructural characterizations were carried out by XRD, optical and scanning electron microscopes. Biocorrosion properties were determined by immersion and electrochemical corrosion tests, performed in a simulated body fluid solution at 37 °C. Compared to the Sr-free alloy, Sr-bearing alloys exhibited a smaller grain size and a higher volume fraction of second-phase particles. The hardness of the alloy was also gradually improved by increasing Sr additions. Biocorrosion properties of the alloy significantly improved by 0.2 wt% Sr addition, and these properties deteriorated with higher additions of Sr due to the strong microgalvanic effect of coarse second-phase particles. Therefore, the ZXM220–0.2Sr alloy can be regarded as a promising candidate for a new biodegradable implant material due to the optimum results of mechanical and biocorrosion properties. [ABSTRACT FROM AUTHOR]

The microstructure of Al-Si-Mg alloys strongly depends on their chemical composition and the heat treatment they undergo during production. The influence of solution heat treatment (SHT) and the addition of Er and Zr on the microstructure of gravity-cast A356 (Al-7Si-0.4Mg) were examined. The reference as-cast microstructure is characterized by the grain size and morphology of eutectic Si, as well as the morphology, area fraction, and chemical composition of the intermetallic compounds. The morphology of eutectic Si is unstable during SHT; the evolution mechanisms can be described using thermodynamic and kinetic models and have been validated using optical and scanning electron microscope (SEM) micrographs. The effect of high-temperature exposure during SHT, on the other hand, plays a minor role on the quantity and morphology of the intermetallic compounds, as demonstrated by optical and SEM micrographs. [ABSTRACT FROM AUTHOR]

The as-extruded NQZ310K (Mg-3.0Nd-1.0Ag-0.2Zn-0.4Zr, mass fraction) alloy was annealed at 300, 350, 400, 450, and 500 °C, respectively. Microstructures of the alloy were observed by an optical microscope and a scanning electron microscope equipped with an energy-dispersive X-ray spectroscope. Ambient mechanical properties were evaluated by tensile tests and nanoindentation tests, and corrosion behavior in simulated body fluid was measured by immersion test. The results show that both matrix grains and precipitates grow up with increasing annealing temperature, and the amount of the precipitates is reduced. The yield strength of the alloy under the as-extruded condition and annealed at 300 and 350 °C is 297, 313, and 298 MPa, and the ultimate tensile strength of it is 327 , 328 , and 315 MPa, respectively, indicating high yield ratio. After annealing at 400, 450, and 500 °C, the yield strength reduces faster than the ultimate tensile strength, resulting in the yield ratio decrease from 0.95 to 0.61, and the elongation improves significantly from 12.3 to 25.5%. The alloy annealed at 350 °C presents the lowest corrosion rate, and then the corrosion resistance of the alloy decreases with increasing annealing temperature. The effects of annealing on microstructure, mechanical and corrosion properties of the as-extruded NQZ310K alloy were also compared with the properties of solution treated alloy. [ABSTRACT FROM AUTHOR]

In the current research, the effect of Ag on the mechanical properties of Ti5Al2.5Fe alloy was investigated. The Ti5Al2.5Fe alloy, with different amounts of Ag ranged from 1 to 5 wt. % was prepared by mechanical mixing and then fabricated by hot pressing at 950 oC for 15 min under 50 MPa. Three holding steps were applied to the powder compacts to restrain the liquid phases inside graphite die before reaching the maximum sintering temperature. The sintered samples were subjected to hardness, bending and wear tests to study the effect Ag on the mechanical properties of Ti5Al2.5Fe alloy. The microstructural characterization was carried out by means of optical and scanning electron microscope. The results showed that Ag played a differential role on the mechanical properties supported by microstructural constituents. The bending strength and hardness of the produced samples increased with the addition of Ag, the hardness of the alloys then tended to decrease with increasing Ag content but still remained above the hardness of Ti5Al2.5Fe alloy. Wear test also showed similar trends with hardness test results. Finally, the optimum Ag content for the Ti5Al2.5Fe alloy was determined as 1 wt.%. XRD analysis showed that undissolved Ag content was the main reason for the decrease in the mechanical properties. [ABSTRACT FROM AUTHOR]

Optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM) and tensile machine were used to characterize the microstructures and mechanical properties of as-forged and aged Mg-9.5Gd-3.8Y-0.6Zr alloys. The results show that a novel kind of dislocation arrays, comprising parallel arranged dislocations, were obtained in the forged alloy. The arrays tend to extend parallel and are heterogeneously distributed with adjacent distances varying from 0.3 µm to 1.4 µm. After aging the alloy at 265 °C, a large number of preferential-oriented β' phases were precipitated on the dislocation arrays, forming a structure of "precipitation chains" (PCs), which results in simultaneous increments of strength and ductility. [ABSTRACT FROM AUTHOR]

Dynamic plastic deformation (DPD) achieved by multipass hammer forging is one of the most important metal forming operations to create the excellent materials properties. By using the integrated approaches of optical microscope and scanning electron microscope, the forging temperature effects on the multipass hammer forging process and the forged properties of Ti-6Al-4V alloy were evaluated and the forging samples were controlled with a total height reduction of 50% by multipass strikes from 925°C to 1025°C. The results indicate that the forging temperature has a significant effect on morphology and the volume fraction of primary α phase, and the microstructural homogeneity is enhanced after multipass hammer forging. The alloy slip possibility and strain rates could be improved by multipass strikes, but the marginal efficiency decreases with the increased forging temperature. Besides, a forging process with an initial forging temperature a bit above β transformation and finishing the forging a little below the β transformation is suggested to balance the forging deformation resistance and forged mechanical properties. [ABSTRACT FROM AUTHOR]

Microstructure, tensile and wear properties of as-cast A4 (Mg-4Al), AE41 (Mg-4Al-0.5Ce-0.5La), AS41 (Mg-4Al-1Si) and AJ41 (Mg-4Al-1Sr) alloys were investigated, and the results were compared with each other in this study. Microstructures were investigated by XRD, optical and scanning electron microscopes. Tensile tests were conducted at both room and elevated temperatures. Tribological properties were examined by pin-on-disk wear tests under different applied loads. Microstructure characterizations revealed that the volume fraction of second phases considerably increased by alloying additions of 1 wt.% Ce/La, Si and Sr. The microstructure of A4 alloy consisted of α-Mg grains and divorced β-Mg17Al12 phases. After individual alloying additions of 1 wt.% Ce/La, Si and Sr, the secondary phases were primarily replaced by needle-shaped and massive blocky-shaped Al11(Ce,La)3 phases in AE41 alloy, Chinese-script-type Mg2Si phases in AS41 alloy and divorced globular-like and massive blocky-shaped Al4Sr and (Mg,Al)17Sr2 phases in AJ41 alloy. The tensile tests showed that at both room and elevated temperatures alloying additions of 1 wt.% Ce/La, Si and Sr resulted in an increase in the strength but a decrease in the ductility. Among the studied alloys, AS41 alloy exhibited the best strength. Wear test results showed that AE41 and AJ41 alloys similarly exhibited the best wear resistance owing to the presence of hard and dense intermetallics. Abrasion was the main wear mechanism under low applied loads while delamination, adhesion and oxidation mechanisms were majorly observed under high applied loads. [ABSTRACT FROM AUTHOR]

In the present study, the microstructure and elevated-temperature mechanical properties of Mg-6Al, Mg-6Al-4Ca, Mg-6Al-4Sm and Mg-6Al-2Ca-2Sm alloys were investigated. The experimental results showed that the microstructure and elevated-temperature mechanical property of Mg-6Al alloy changed obviously with the different elements addition. By analyzing the results of optical microscope, x-ray diffraction analysis, scanning electron microscope, and transmission electron microscope, it could be determined that there was only Mg17Al12 phase in Mg-6Al alloy, there were Al2Ca and (Mg, Al)2Ca phases in Mg-6Al-4Ca alloy, there were Al2Sm and Mg17Al12 phases in Mg-6Al-4Sm alloy, and there were (Mg, Al)2Ca, Al2Ca and Al2Sm phases in Mg-6Al-2Ca-2Sm alloy. In addition, the addition of alloying elements including Ca and Sm, especially the composite addition, could significantly improve the tensile properties of Mg-6Al alloy. Compared to Mg-6Al alloy, the tensile strengths of Mg-6Al-2Ca-2Sm alloy at 448, 473 and 498 K were enhanced by 50.32, 87.92, and 94.99%, respectively. Furthermore, when the stretching temperatures were 448 and 473 K, the fracture pattern of Mg-6Al-2Ca-2Sm alloy was the mixture of intergranular fracture and trans-crystalline fracture. However, when the stretching temperature was 498 K, the fracture pattern of Mg-6Al-2Ca-2Sm alloy was the intergranular fracture. [ABSTRACT FROM AUTHOR]

The effect of initial Fe content on the iron removal efficiency, morphology evolution of the Fe-rich phase and the mechanical properties of the recycled Al-7Si-xFe-1.2xMn alloy during melt holding was studied using an optical microscope (OM), scanning electron microscope (SEM) and tensile testing. The results show that with the increase of the initial Fe content, the residual Fe concentration of the alloys gradually increased, and the corresponding removal efficiency of Fe gradually was increased to 77.67%. The type of Fe-rich phase in the alloys changes from α-Al15(FeMn)3Si2 to a mixture of α-Al15(FeMn)3Si2 and β-Al5FeSi, and its morphological evolution is as follows: coarse Chinese-script + polygon → dense Chinese-script + polygon → polygonal + dense Chinese-script + plate-like. Furthermore, the morphology of the Fe-rich phase in the slag changes from a polygonal shape to an irregular shape with a two-layer structure. The formation and increase of the inner layer with high Mn-content in the irregular-shape phase is the main reason for the increasing residual Fe content. The plasticity of the alloy increases obviously with the increase of the initial Fe content, but the formation of the β-Al5FeSi with plate-like morphology in higher Fe-containing alloy may hinder further improvement of the plasticity. [ABSTRACT FROM AUTHOR]

The refining performance of Al-Ti-C master alloys is substantially compromised by the inferior wettability between graphite and molten aluminum. In this paper, the Al-5Ti-0.25C master alloy was successfully prepared by reacting Ti machining chips, graphite, and molten aluminum. In order to determine a simple method of improving the wettability, the optimal preparation process and phase transformation of the Al-5Ti-0.25C master alloy were investigated using an optical microscope, X-ray diffractometer, and scanning electron microscope equipped with an energy dispersive spectrometer. The results show that the feeding method using a prefabricated block made from Ti chips, Al chips, and graphite effectively improves the wettability between graphite and molten aluminum and increases the recovery rate of graphite. When the reaction temperature is low (1223 K), the agglomeration of TiAl3 is caused. When the reaction temperature is high (1373 K), the morphology of TiAl3 changes from block-like to needle-like and increases its size. Further, a short reaction time (30 min) results in the incomplete dissolution of the Ti chips, while a long reaction time (90 min) causes the TiAl3 to transform into needle-like morphologies. The microstructural observation of undissolved Ti chips shows that TiAl3 and TiC are formed around it, which proves the transformation of Ti chips to TiAl3 and TiC. In addition, the enrichment of TiC and Al4C3 was observed in the vicinity of TiAl3, and a reaction model for the formation of TiC from the reaction of Al4C3 and TiAl3 was presented. [ABSTRACT FROM AUTHOR]

This research shows an extensive analysis of the microstructural, mechanical, and tribological response in a cast Al–Mg–Zn alloy processed through ECAP, developed in order to obtain a material with similar properties of the Al-7075 T6 alloy. Microstructure of the Al–Mg–Zn alloy was analyzed through optical and scanning electron microscope; on the other hand, wear tests were carried out on ball-on-disc tribometer according to the ASTM-G99. Before and after processing, mechanical properties were evaluated through microhardness measurements. Furthermore, wear mechanisms and friction coefficient in the Al–Mg–Zn alloy were analyzed and correlated with microstructure and mechanical properties after deformation process, while these results were compared with the properties of the Al-7075 T6 alloy. Results showed that ECAP process improves the mechanical properties, however, a wear resistance decrement in terms of wear rate and friction coefficient was observed. • Wear behavior of ECAP processed As cast was investigated and compared with AL-7075T6. • The wear mechanism observed has related with the fragmentation of intermetallics phases. • For a higher number of ECAP passes was observed a grains size reduction and redistribution and fragmentation of second phase particles. • The ECAP process show an improvement of mechanicals properties but a decrement of tribological behavior. [ABSTRACT FROM AUTHOR]

To enhance the mechanical properties (e.g., strength and elongation) of the face-centered cubic (fcc) α-phase in the Au-Cu-Al system, this study focused on the introduction of the martensite phase (doubled B19 (DB19) crystal structure of Au2CuAl) via the manipulation of alloy compositions. Fundamental evaluations, such as microstructure observations, phase identifications, thermal analysis, tensile behavior examinations, and reflectance analysis, have been conducted. The presence of fcc annealing twins was observed in both the optical microscope (OM) and the scanning electron microscope (SEM) images. Both strength and elongation of the alloys were greatly promoted while the DB19 martensite phase was introduced into the alloys. Amongst all the prepared specimens, the 47Au41Cu12Al and the 44Au44Cu12Al alloys performed the optimized mechanical properties. The enhancement of strength and ductility in these two alloys was achieved while the stress plateau was observed during the tensile deformation. A plot of the ultimate tensile strength (UTS) against fracture strain was constructed to illustrate the effects of the introduction of the DB19 martensite phase on the mechanical properties of the alloys. Regardless of the manipulation of the alloy compositions and the introduction of the DB19 martensite phase, the reflectance stayed almost identical to pure Au. [ABSTRACT FROM AUTHOR]

Fretting wear evolution of γ-TiAl alloy was investigated. Evolution of wear scar, tribolayer and wear debris were studied using optical microscope and scanning electron microscope. The results show that the wear debris generated from γ-TiAl alloy can be compacted to form a tribolayer rapidly after 100 fretting cycles. At the starting stage, the rapid formation and rupture of tribolayer alternatively occur due to insufficient thickness of the tribolayer. With the proceeding of fretting, the thickness of tribolayer increases due to increase in the amount of the wear debris, which makes the tribolayer more stable. The evolution of the wear debris and the formation of tribolayer significantly influence the fretting wear behavior of γ-TiAl alloy. The wear rate of γ-TiAl alloy decreases rapidly from 255.6 × 10−3μm3 /(N·μm) after 2000 fretting cycles to 35.5 × 10−3μm3 /(N·μm) after 10,000 fretting cycles when a thick tribolayer is formed. A physical model was proposed to describe the evolution process of the fretting wear of γ-TiAl alloy. • Wear debris of γ-TiAl alloy can be compacted to form a tribolayer rapidly. • Rapid rupture of tribolayer occur due to insufficient thickness. • Increase in thickness makes tribolayer more stable. • Evolution of tribolayer significantly influences fretting wear of γ-TiAl alloy. [ABSTRACT FROM AUTHOR]

• The secondary acicular β-phase appeared after a 650 °C–1000 h aged process and significantly increased in quantity for 3000 h. • The morphology and quantity of the primary β phase changed significantly with the prolonged aging time. Taking the GH783 alloy bolt of intermediate pressure main stop valve used in 1000 MW ultra-supercritical unit as the research object, the optical microscope (OM), scanning electron microscope (SEM), transmission electron microscope (TEM), X-ray diffractometer (XRD) and mechanical performance tests were carried out to study the microstructure transformation and mechanical properties of GH783 alloy bolts at different aging stages under 650 °C aging environment. The results showed that the secondary needle β phase began to appear in the bolts aged for 1000 h, and the density of secondary β-phases in bolts aged for 3000 h significantly increased. When the aging time reached up to 20,000 h, the secondary β phase coarsened significantly. At the same time, as the aging time prolonged, the morphology and quantity of the primary β phase changed significantly. In terms of mechanical properties, the tensile strength and impact toughness of the bolts gradually decreased. This was due to the growing γ' phase, the formation of Ni 5 Al 3 phase and the Nb-rich Laves phase in the structure during the aging process. [ABSTRACT FROM AUTHOR]

Serration behavior is a kind of plastic instability phenomenon of materials, which widely exists in the high-entropy alloys and has influence on microstructure and mechanical properties. In this work, the microstructure and mechanical properties of a NiCrFeCoMn high-entropy alloy (HEA) were studied under high-speed impact. The microstructure of a NiCrFeCoMn HEA were investigated by optical microscope (OM), scanning electron microscope (SEM), electron backscatter diffraction (EBSD), and transmission electron microscope (TEM). The dislocation density increased with the true strain at high-strain-rate deformation, and the dislocations can be hindered and released continually by the twin layers, resulting in serration on the true stress—true strain curve. When values of the strain rates are 1250, 2000 and 4800 s−1, the yield strength of the deformed NiCrFeCoMn HEA are 510, 525 and 680 MPa, respectively. Moreover, the fluctuation of the serration became more serious with the increasing of the strain rate. Compared with the as-cast NiCrFeCoMn HEA, the true stress—true strain curve of the deformed NiCrFeCoMn HEAwas smoother. [ABSTRACT FROM AUTHOR]

In this study, the plastic flow and ductile fracture of three 6000-series aluminium alloys commonly used for crash components in the automotive industry are characterised experimentally and the observations are related to microstructural features. The three alloys are used in the cast and homogenised condition after artificial ageing to temper T6 to ensure isotropic behaviour. Tension tests on smooth and notched axisymmetric specimens are carried out to reveal the stress–strain behaviour, ductility and fracture mechanisms of the materials for different stress states. Through the use of optical and scanning electron microscopes, the initial microstructure of the alloys and the fracture surfaces of the tension test specimens are investigated. The work-hardening of the alloys is analysed up to large strains. Whereas the ductility of two of the alloys falls into the trend of previous experimental data on 6000-series aluminium alloys, where the strain to failure decreases linearly with increasing yield stress, the third alloy stands out by combining high strength with high ductility. The excellent properties of the latter alloy are assumed to be due to a favourable size distribution of constituent particles. [ABSTRACT FROM AUTHOR]

Selective laser melting (SLM) is a promising additive manufacturing technique with growing acceptance in aerospace applications. In this work, a new aeronautical material of near-α Ti alloy (TA15) for SLM was firstly investigated and analyzed before and after annealing, mainly including mechanical properties, microstructural evolution. The distinctions between SLMed TA15 and wrought TA15 are also discussed in this study. Firstly, near full density TA15 samples (99.98%) were fabricated by SLM utilizing the optimized processing parameters. Then microstructures and textures are characterized and analyzed by optical microscope, X-ray diffractometer, scanning electron microscope and transmission electron microscope. Furthermore, mechanical properties of TA15 samples are measured via tensile and hardness test, considering the impacts of building direction. The results show that both the as-built and the annealed SLMed samples exhibit significantly weak textures and unconspicuous anisotropy of mechanical properties. It has been identified that αʹ martensite is dominant in the as-built microstructure thus contributing to ~1296 MPa in ultimate strength and ~398 HV in hardness which are 35% and 24% higher than those of wrought material. However, a low plasticity with ~7.6% of elongation at break was observed. After annealing, SLMed samples exhibited excellent comprehensive mechanical properties with 51% improvement at elongation through elimination of residual stress and precipitation of nanometer size β phase in the fine basket-weave structure. [ABSTRACT FROM AUTHOR]

The Mg–1Al– x Y (x = 3, 5, 8) alloys were prepared by melting technology and extruded at 400 °C. Microstructures of the alloys were investigated by X-ray diffraction (XRD), optical microscope (OM), and scanning electron microscope (SEM). Tensile properties of the alloys were measured. The results showed that the as-extruded Mg–1Al– x Y (x = 3, 5, 8) alloys were composed of α-Mg phase and Al 2 Y phase and the microstructures were main dynamic recrystallization. The eutectic Al 2 Y phase was broken down to finer particles and dispersed more uniformly after the extrusion. The extruded alloys have (0002) basal plane texture. The tensile strength, yield strength and elongation of Mg–1Al–8Y alloy were 288 MPa, 174 MPa and 20% at room temperature, respectively. Therefore, the alloys have good mechanical properties and the fracture morphology with ductile features. [ABSTRACT FROM AUTHOR]