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The primary objective of this study is to investigate the microstructural, mechanical, and wear behaviour of AZ31/TiC surface composites fabricated through friction stir processing (FSP). TiC particles are reinforced onto the surface of AZ31 magnesium alloy to enhance its mechanical properties for demanding industrial applications. The FSP technique is employed to achieve a uniform dispersion of TiC particles and grain refinement in the surface composite. Microstructural characterization, mechanical testing (hardness and tensile strength), and wear behaviour evaluation under different operating conditions are performed. Response surface methodology (RSM) is utilized to optimize the wear rate by considering the effects of process parameters. The results reveal a significant improvement in hardness (41.3%) and tensile strength (39.1%) of the FSP-TiC composite compared to the base alloy, attributed to the refined grain structure (6–10 μm) and uniform distribution of TiC particles. The proposed regression model accurately predicts the wear rate, with a confirmation test validating an error percentage within ± 4%. Worn surface analysis elucidates the wear mechanisms, such as shallow grooves, delamination, and oxide layer formation, influenced by the applied load, sliding distance, and sliding velocity. The enhanced mechanical properties and wear resistance are attributed to the synergistic effects of grain refinement, particle-accelerated nucleation, the barrier effect of TiC particles, and improved interfacial bonding achieved through FSP. The optimized FSP-TiC composites exhibit potential for applications in industries demanding high strength, hardness, and wear resistance. [ABSTRACT FROM AUTHOR]

In this study, a novel localized selective remelting technique was proposed to treat the welding interface regions on the top and bottom surfaces of the AZ31 friction stir welded joint. Compared with the untreated joint, the treated joint achieved a favorable combination of strength (ultimate tensile strength of 238 MPa) and ductility (elongation of 13.3%). Digital image correlation (DIC) characterization revealed that the high strain-hardening ability primarily stemmed from the substantial mitigation of strain localization, which was caused by a comprehensive factor, including reduced SF value fluctuation between weld micro-zones, low residual dislocation density, and numerous extension twinning activation in the nugget zone.

Abstract The primary objective of this study is to investigate the microstructural, mechanical, and wear behaviour of AZ31/TiC surface composites fabricated through friction stir processing (FSP). TiC particles are reinforced onto the surface of AZ31 magnesium alloy to enhance its mechanical properties for demanding industrial applications. The FSP technique is employed to achieve a uniform dispersion of TiC particles and grain refinement in the surface composite. Microstructural characterization, mechanical testing (hardness and tensile strength), and wear behaviour evaluation under different operating conditions are performed. Response surface methodology (RSM) is utilized to optimize the wear rate by considering the effects of process parameters. The results reveal a significant improvement in hardness (41.3%) and tensile strength (39.1%) of the FSP-TiC composite compared to the base alloy, attributed to the refined grain structure (6–10 μm) and uniform distribution of TiC particles. The proposed regression model accurately predicts the wear rate, with a confirmation test validating an error percentage within ± 4%. Worn surface analysis elucidates the wear mechanisms, such as shallow grooves, delamination, and oxide layer formation, influenced by the applied load, sliding distance, and sliding velocity. The enhanced mechanical properties and wear resistance are attributed to the synergistic effects of grain refinement, particle-accelerated nucleation, the barrier effect of TiC particles, and improved interfacial bonding achieved through FSP. The optimized FSP-TiC composites exhibit potential for applications in industries demanding high strength, hardness, and wear resistance.

Magnesium (Mg) and its alloys offer promise for aerospace, railway, and 3D technology applications, yet their inherent limitations, including inadequate strength, pose challenges. Magnesium matrix composites, particularly with metallic reinforcements like titanium (Ti) and its alloys, present a viable solution. Therefore, this study investigates the impact of Ti6Al4V reinforcement on AZ31 magnesium alloy composites produced using pulse plasma sintering (PPS). Results show enhanced microhardness of the materials due to improved densification and microstructural refinement. However, Ti6Al4V addition decreased corrosion resistance, leading to strong microgalvanic corrosion and substrate dissolution. Understanding these effects is crucial for designing Mg-based materials for industries like petrochemicals, where degradation-resistant materials are vital for high-pressure environments. This research provides valuable insights into developing Mg-Ti6Al4V composites with tailored properties for diverse industrial applications, highlighting the importance of considering corrosion behavior in material design. Further investigation is warranted to establish predictive correlations between Ti6Al4V content and corrosion rate for optimizing composite performance. [ABSTRACT FROM AUTHOR]

Coarse grain and poor thermal stability of Mg17Al12 are usually present in the as-cast Mg–Al alloys, which are detrimental to the mechanical properties. In this work, the microstructure evolution, and mechanical properties of as-cast AZ31-1Y alloy with different cooling rates (4.0–29.9 °C/s) were systematically investigated by thermal analysis and microstructure characterization. The results show that the addition of Y to AZ31 alloy results in the formation of primary Al2Y and eutectic Al2Y, while suppressing the formation of β-Mg17Al12. The AZ31-1Y alloy with a cooling rate of 29.9 °C/s exhibits the finest grain, with a grain refinement efficiency 40.9 % higher than that of AZ31 alloy with a cooling rate of 4.0 °C/s. After heat treatment, the acicular eutectic Al2Y is modified into a granular shape and numerous nano-sized Al2Y precipitates are observed within the α-Mg matrix. The addition of Y can effectively improve the mechanical properties of AZ31 alloy under high cooling rates, but the mechanical properties deteriorate at slower cooling rates due to stress concentration caused by the agglomeration of large-sized Al2Y particles. The optimal mechanical properties of the AZ31-1Y alloy are achieved at a cooling rate of 29.9 °C/s combined with subsequent heat treatment, and its YS, UTS, and EL reached up to 69 MPa, 293 MPa, and 14.5 %, respectively. Moreover, the related strengthening mechanisms are quantified. It is believed that this work can provide guidance for controlling the microstructure and optimizing the mechanical properties of as-cast Mg–Al alloys.

In this work, the AZ31 Mg alloy was subjected to friction stir processing (FSP) by adding CuO and ZrO2 particles. The main aim of this study was to increase the tribological and mechanical behavior of AZ 31/(CuO + ZrO2)p surface composite in air and water. The influence of the processing media on the microstructural modification and mechanical properties of the developed composites is assessed via optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), shear punch testing (SPT) and Vickers hardness testing. It had been found that finer grains are produced in the stir zone due to the reduction in heat input for the water-cooled composite relative to the air-cooled composite. Indeed, the water-cooling system acted as a hamper and suppressed grain growth, which consequently resulted in the enhancement of the mechanical and tribological behavior of the AZ 31/(CuO + ZrO2)p surface composite.

In this research, tin was added to the AZ31/2Al2O3 magnesium metal matrix composite to investigate its influence on degradation rate in the presence of simulated body fluid (SBF) and wear behaviour in dry conditions. The AZ31- x Sn/2Al2O3 (x = 0, 2, 4, 6, 8, and 10 wt%) composites were manufactured using the bottom pouring stir casting route. The microstructure of the manufactured AZ31/2Al2O3 and AZ31- x Sn/2Al2O3 composites revealed that they were composed of the α-Mg solid solution and the intermetallic compound □-Mg17Al12, which was situated near the grain boundaries. When tin was added, the Sn-rich intermetallic compound Mg2Sn was formed, increasing the volume fraction of the Mg2Sn phase. Compared to AZ31/2Al2O3 composite, the wear test revealed that AZ31/2Al2O3 composites containing Sn particles exhibited a higher ability to generate more stable tribo-layers at higher applied loads, which protected the worn surface and reduced the wear rate. The wear resistance of composites was improved primarily by the behaviour of the tribo-layer in the wear process. The degradation rates (mm/year) of the AZ31 composites were carried out for 72 h in SBF. The degradation rate was reduced when the Sn content in the AZ31/2Al2O3 composite was increased to 6 wt% and then increased with further Sn addition. It was observed that when the amount of Sn particles increases up to 6 wt%, the severity of the degradation decreases. [ABSTRACT FROM AUTHOR]

Thermomechanical processing and alloying are two common approaches to enhance the mechanical properties of Mg. Thus, the effects of Gd and Li elements, as two elements with various properties, on the microstructure and mechanical properties of a hot-rolled and consequently annealed AZ31 alloy were analyzed. The microstructure and texture was analyzed by scanning electron microscopy and electron back scattered diffraction. Accordingly, the mean grain size of 46 μm in the AZ31 alloy was reduced to 41 and 26 μm in the AZ31–2.9Gd and AZ31–2.3Li alloys, respectively. Grain refinement occurred due to continuous dynamic recrystallization and twinning-induced recrystallization in all of the alloys. Textural evolution showed that neither Gd nor Li could inhibit the occurrence of basal texture. Room temperature mechanical properties were assessed by using the shear punch test (SPT) method. The results exhibited that the strength of the AZ31 alloy was improved from 116 MPa to 139 MPa and 141 MPa by respective additions of Gd and Li. Strength enhancement was mainly attributed to the grain boundary strengthening and second-phase particles hardening. One promising observation was the simultaneous enhancement of shear strength and ductility by the addition of Gd and Li. This observation was ascribed to the more uniform distribution of second-phase particles and lower volume fraction of twins as potential sites for crack initiation. As long as mechanical strength is concerned, results favor the use of Li as alloying element in Mg, especially due to the more noticeable lightweighting potential compared to Gd.

Magnesium alloys have excellent properties such as high specific strength, rigidity, good damping, electromagnetic shielding, castability, and machinability. However, corrosion, creep, and fatigue resistance are generally the properties that need to be improved. In this study, a hybrid coating was formed on AZ31 magnesium alloy with different surface roughness at different frequencies. In the hybrid coating, an oxide coating was first grown on the surface by the micro-arc oxidation method, and then, the epoxy coating was grown on this oxide coating by the dipping method. The characterization of the coatings was performed by XRD, SEM, and EDS analysis. Furthermore, the relationship between fatigue life and surface roughness was also discussed in this study. The fatigue life and strength of the coated samples were determined as a result of the tests performed on the fatigue device. It was concluded that the fatigue life and strength of hybrid coatings were much better compared to uncoated and single-layer coated samples. [ABSTRACT FROM AUTHOR]

Electrochemical micromachining (ECM) is a nontraditional method used for machining operations in hard and light materials with fixed or varying parameters. In this study, magnesium AZ31 alloy was micro machined using two types of electrolyte supply systems, namely electrolyte flooding and minimum quantity electrolyte (MQE). Experimental investigations were performed using TOPSIS and artificial neural network (ANN) techniques with types of electrolyte supply system, electrolyte concentration (EC), duty cycle (%), and machining voltage (V) as the input parameters, and material removal rate (MRR) and over cut (OC) as the outputs. Single and multi-objective parameter optimization was performed using Taguchi, TOPSIS, and ANN techniques. The machined microholes were analyzed using scanning electron microscopy. According to the TOPSIS results, under optimal conditions, a high MRR value and minimum OC of 1.282 µm/s and 66 µm, respectively, were obtained. The results of TOPSIS were verified using the developed ANN architecture. [ABSTRACT FROM AUTHOR]

In this study, the effects of silicon nitride (Si3N4) particles on the microstructure and corrosion characteristics of AZ31 matrix composites in a 3.5% NaCl solution are examined with the help of an electrochemical test. Varying wt.% of Si3N4 particles (2, 4, 6, 8, 10, and 12 %) is used to fabricate matrix composites via a vacuum-assisted stir-casting approach. The developed composites and base alloys are characterized by energy dispersive X-ray analysis (EDAX) and scanning electron microscopy (SEM). Microscopic images demonstrate that the addition of reinforcement enhances the microstructural interfacial integrity between the Si3N4 and AZ31 matrix. EDAX results confirm the presence of Si3N4 particles in composites. The findings of electrochemical studies confirmed that AZ31's corrosion resistance substantially improved as its Si3N4 content increased. AZ31-10%Si3N4 exhibits a more tremendous corrosion potential (Ecorr) and a two-order-of-magnitude lower corrosion current density (icorr). Compared to the other samples, AZ31-10%Si3N4 exhibits superior polarization resistance. Compared to AZ31-2%Si3N4, AZ31-10%Si3N4 exhibits a 3.5-fold increase in polarization resistance. The results show that the AZ31 alloy with 10% Si3N4 exhibits superior corrosion resistance, followed by the AZ31-12%Si3N4, AZ31-8%Si3N4, AZ31-6%Si3N4, AZ31-4%Si3N4, and AZ31-2%Si3N4. The collective outcomes of the investigation indicate that the AZ31-10%Si3N4 composite may have the potential to enhance the corrosion behavior of AZ31 alloys.

This paper focuses on modeling the tribological properties of AZ31-SiC composite using an artificial neural network (ANN) fabricated through the stir casting method. The twenty-seven tests were performed with three loads (10 N, 15 N, and 20 N), three sliding speeds (0.5 m/s, 1.0 m/s, and 1.5 m/s), and three sliding distances (500 m, 750 m, and 1000 m) on wear testing machine and are used in the formation of training sets of ANN. Using the wear test data, Taguchi, Analysis of Variance (ANOVA), and regression analysis were carried out to determine the effect of the control parameters on the wear and coefficient of friction (COF). The experimental results demonstrate that the wear rate increases with an increase in load and distance and decreases with an increase in velocity. In addition, an alternative method is proposed to predict the wear and COF using ANN modeling with single and multi-hidden layer techniques. With good training, ANN gives accurate and close results to the experimental results. The results obtained using ANN modeling have a percentage of error of 4.71% and 5.79% for wear and COF respectively, when compared to experimental values. This prediction process saves time and costs for the manufacturer.

Nano-sized reinforcements improved the mechanical characteristics efficiently by promoting more implicit particle hardening mechanisms compared to micron-sized reinforcements. Nano-sized particles lessen the critical particle solidification velocity for swamp and thus offers better dispersal. In the present investigation, the friction stir processing (FSP) is utilized to produce AZ31/Al2O3 nanocomposites at various tool rotation speeds (i.e., 900, 1200, and 1500 rpm) with an optimized 1.5% volume alumina (Al2O3) reinforcement ratio. The mechanical and corrosion behavior of AZ31/Al2O3-developed nanocomposites was investigated and compared with that of the AZ31 base alloy. The AZ31 alloy experienced a comprehensive dynamic recrystallization during FSP, causing substantial grain refinement. Grain-size strengthening is the primary factor contributed to the enhancement in the strength of the fabricated nanocomposite. Tensile strength and yield strength values were lower than those for the base metal matrix, although an upward trend in both values has been observed with an increase in tool rotation speed. An 19.72% increase in hardness along with superior corrosion resistance was achieved compared to the base alloy at a tool rotational speed of 1500 rpm. The corrosion currents (Jcorr) of all samples dropped with increase in the rotational speed, in contrast to the corrosion potentials (Ecorr), which increased. The values of Jcorr of AZ31/Al2O3 were 42.3%, 56.8%, and 65.5% lower than those of AZ31 alloy at the chosen rotating speeds of 900, 1200, and 1500 rpm, respectively. The corrosion behavior of friction stir processed nanocomposites have been addressed in this manuscript which has not been given sufficient attention in the existing literature. Further, this work offers an effective choice for the quality assurance of the FSP process of AZ31/Al2O3 nanocomposites. The obtained results are relevant to the development of lightweight automobile and aerospace structures and components.

This study investigated the effects of mechanical-polishing-induced surface roughness and the direction of polishing lines on the bending properties of a rolled AZ31 alloy. To this end, three-point bending tests were performed on one sample without polishing lines (SS sample) and two samples with polishing lines—one in which the polishing lines were parallel to the rolling direction (RS-RD sample) and the other in which they were parallel to the transverse direction (RS-TD sample). In all three samples, macrocracks were formed in the width direction on the outer surface, where tensile stress was predominantly generated in the longitudinal direction. However, the macrocracks formed in the SS sample were curved because of the merging of uniformly formed fine microcracks, whereas those formed in the RS-TD sample were linear owing to the formation of relatively coarse microcracks along the polishing lines. The bendability of the samples was in the order of SS > RS-RD > RS-TD, and their limiting bending depths were 4.8, 4.6, and 4.4 mm, respectively. In the presence of mechanical-polishing-induced surface roughness, polishing lines perpendicular to the direction of the major stress (i.e., tensile stress along the longitudinal direction) resulted in a greater degree of stress concentration on the outer surface of the bending specimen. This higher stress concentration promoted the formation of undesirable {10–11} contraction and {10–11}–{10–12} double twins—which typically act as crack initiation sites—and thereby facilitated crack generation and propagation. Consequently, the surface roughness caused premature fracture during bending deformation, which, in turn, caused deterioration of the bendability of the rolled Mg alloy.

This paper focuses on modeling the tribological properties of AZ31-SiC composite using an artificial neural network (ANN) fabricated through the stir casting method. The twenty-seven tests were performed with three loads (10 N, 15 N, and 20 N), three sliding speeds (0.5 m/s, 1.0 m/s, and 1.5 m/s), and three sliding distances (500 m, 750 m, and 1000 m) on wear testing machine and are used in the formation of training sets of ANN. Using the wear test data, Taguchi, Analysis of Variance (ANOVA), and regression analysis were carried out to determine the effect of the control parameters on the wear and coefficient of friction (COF). The experimental results demonstrate that the wear rate increases with an increase in load and distance and decreases with an increase in velocity. In addition, an alternative method is proposed to predict the wear and COF using ANN modeling with single and multi-hidden layer techniques. With good training, ANN gives accurate and close results to the experimental results. The results obtained using ANN modeling have a percentage of error of 4.71% and 5.79% for wear and COF respectively, when compared to experimental values. This prediction process saves time and costs for the manufacturer. [ABSTRACT FROM AUTHOR]

Nano-sized reinforcements improved the mechanical characteristics efficiently by promoting more implicit particle hardening mechanisms compared to micron-sized reinforcements. Nano-sized particles lessen the critical particle solidification velocity for swamp and thus offers better dispersal. In the present investigation, the friction stir processing (FSP) is utilized to produce AZ31/Al 2 O 3 nanocomposites at various tool rotation speeds (i.e., 900, 1200, and 1500 rpm) with an optimized 1.5% volume alumina (Al 2 O 3) reinforcement ratio. The mechanical and corrosion behavior of AZ31/Al 2 O 3 -developed nanocomposites was investigated and compared with that of the AZ31 base alloy. The AZ31 alloy experienced a comprehensive dynamic recrystallization during FSP, causing substantial grain refinement. Grain-size strengthening is the primary factor contributed to the enhancement in the strength of the fabricated nanocomposite. Tensile strength and yield strength values were lower than those for the base metal matrix, although an upward trend in both values has been observed with an increase in tool rotation speed. An 19.72% increase in hardness along with superior corrosion resistance was achieved compared to the base alloy at a tool rotational speed of 1500 rpm. The corrosion currents (Jcorr) of all samples dropped with increase in the rotational speed, in contrast to the corrosion potentials (Ecorr), which increased. The values of Jcorr of AZ31/Al 2 O 3 were 42.3%, 56.8%, and 65.5% lower than those of AZ31 alloy at the chosen rotating speeds of 900, 1200, and 1500 rpm, respectively. The corrosion behavior of friction stir processed nanocomposites have been addressed in this manuscript which has not been given sufficient attention in the existing literature. Further, this work offers an effective choice for the quality assurance of the FSP process of AZ31/Al 2 O 3 nanocomposites. The obtained results are relevant to the development of lightweight automobile and aerospace structures and components. [ABSTRACT FROM AUTHOR]

In recent years, a new wave of biocompatable, bioactive, bioresorbable and biodegradable metals were developed by researchers for biomedical applications because of the excellent properties of magnesium metal matrix composite. This present study aims to fabricate the AZ31-Sn/2 wt% nano-Al2O3 composites with various weight fractions (0, 2, 4, 6, 8 and 10 wt%) of micro-tin (Sn) particles using the stir casting technique. The effect of Sn particles reinforcement on mechanical properties, microstructure and wear performance was examined. The EDX analyses and scanning electron microscopy were used to study the hard particles distribution and the interface between the AZ31 alloy and reinforcement particles. The mechanical properties and wear behaviour are increased in AZ31-Sn/nano-Al2O3 composites compared with the AZ31/nano-Al2O3 composites. Furthermore, these outcomes recommend that for applications demanding high compressive strength and wear performance, the AZ31-Sn/nano-Al2O3 will be effective composites. [ABSTRACT FROM AUTHOR]

Friction stir welding (FSW) is a new solid-state joining process for joining light metals, such as magnesium (Mg) alloys. However, the texture-induced softening mechanism (in stir zone, SZ) tends to cause the worsening of mechanical properties in FSW Mg alloys. In this work, multi-pass hot-rolling and subsequent annealing is used to ameliorate the FSW AZ31 alloy plate. The results show that multi-pass hot-rolling leads to the c-axes of most grains in the SZ approximately perpendicular to the normal direction (ND) transforming into these almost parallel to the ND, accompanied with multiple twin types. After subsequent annealing, twins, as nucleation sites, promote the formation of new grains with off-basal texture, resulting in the weak basal texture. Compared with the FSW plate and the initial plate, the rolled-annealed FSW plate exhibits a relatively uniform hardness distribution and a “strength-ductility” synergy, which are mainly attributed to an appropriate texture feature and a homogeneous grain structure. This work provides a new idea for the development of new high-performance FSW Mg alloys.

A single-pass gradient caliber rolling of a conical-shaped AZ31 Mg alloy was performed at 723 K to obtain a transitional microstructure with strain ranging from 0 to 30%. The recrystallization mechanisms involved and the evolution of texture during the deformation were specifically investigated. The results show that the recrystallization extent increases with strain. The isolated fine grains at 5% strain were formed by the particle stimulated nucleation, which tended to randomize the texture. A large number of {10 1¯ 2} extension twins at 10% strain effectively divided and refined the grains, but no twin-induced dynamic recrystallization was found. Some {10 1¯ 1}-{10 1¯ 2} double twins and {10 1¯ 1} compression twins were activated at 15% strain, which to a certain extent facilitated dynamic recrystallization nucleation. Meanwhile, the continuous dynamic recrystallization and discontinuous dynamic recrystallization mechanisms also occurred at various strains. In particular, the discontinuous dynamic recrystallization was more prominent due to the higher deformation temperature, and the recrystallization grains were evidently different from the orientations of their parent grains. In addition, with increasing strain, the overall texture component of the deformed samples gradually transitioned from the initial (0001) basal texture to the [11 2¯ 0]-[10 1¯ 0] non-fiber component, then tended to form the [11 2¯ 0] fiber orientation eventually.

Magnesium (Mg) and its alloys offer promise for aerospace, railway, and 3D technology applications, yet their inherent limitations, including inadequate strength, pose challenges. Magnesium matrix composites, particularly with metallic reinforcements like titanium (Ti) and its alloys, present a viable solution. Therefore, this study investigates the impact of Ti6Al4V reinforcement on AZ31 magnesium alloy composites produced using pulse plasma sintering (PPS). Results show enhanced microhardness of the materials due to improved densification and microstructural refinement. However, Ti6Al4V addition decreased corrosion resistance, leading to strong microgalvanic corrosion and substrate dissolution. Understanding these effects is crucial for designing Mg-based materials for industries like petrochemicals, where degradation-resistant materials are vital for high-pressure environments. This research provides valuable insights into developing Mg-Ti6Al4V composites with tailored properties for diverse industrial applications, highlighting the importance of considering corrosion behavior in material design. Further investigation is warranted to establish predictive correlations between Ti6Al4V content and corrosion rate for optimizing composite performance.

This paper compares two types of polylactic acid (PLA) coating on AZ31 alloy obtained by dip coating and electrospinning. Both types of coating were loaded with gentamicin sulphate (GS) and the drug-loading efficiency and release were assessed. A higher encapsulation and release efficiency of GS was seen for dip coating (73% and 49.53%, respectively) compared to nanofiber coating (65% and 12.37%, respectively). Furthermore, the antibacterial effect of the samples with and without GS was assessed using Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria, showing that the samples with the drug encapsulated are more resistant to bacteria than the other samples. The electrochemical data reveal a higher stability in the SBF of the surface obtained by dipping than that obtained by electrospinning. The PLA coating shows a porosity of 46% for the sample obtained through dip coating and 32% for nanofibers, which is in accordance with the BET analysis results. Moreover, a higher adhesion strength was obtained for AZ31-PLA-dip (4.99 MPa) than for the AZ31-PLA-nanofibers (1.66 MPa). All samples were structurally, morphologically, and topographically characterized. [ABSTRACT FROM AUTHOR]

This study investigated the effects of mechanical-polishing-induced surface roughness and the direction of polishing lines on the bending properties of a rolled AZ31 alloy. To this end, three-point bending tests were performed on one sample without polishing lines (SS sample) and two samples with polishing lines—one in which the polishing lines were parallel to the rolling direction (RS-RD sample) and the other in which they were parallel to the transverse direction (RS-TD sample). In all three samples, macrocracks were formed in the width direction on the outer surface, where tensile stress was predominantly generated in the longitudinal direction. However, the macrocracks formed in the SS sample were curved because of the merging of uniformly formed fine microcracks, whereas those formed in the RS-TD sample were linear owing to the formation of relatively coarse microcracks along the polishing lines. The bendability of the samples was in the order of SS > RS-RD > RS-TD, and their limiting bending depths were 4.8, 4.6, and 4.4 mm, respectively. In the presence of mechanical-polishing-induced surface roughness, polishing lines perpendicular to the direction of the major stress (i.e., tensile stress along the longitudinal direction) resulted in a greater degree of stress concentration on the outer surface of the bending specimen. This higher stress concentration promoted the formation of undesirable {10–11} contraction and {10–11}–{10–12} double twins—which typically act as crack initiation sites—and thereby facilitated crack generation and propagation. Consequently, the surface roughness caused premature fracture during bending deformation, which, in turn, caused deterioration of the bendability of the rolled Mg alloy. [ABSTRACT FROM AUTHOR]

The use of bioabsorbable metals as temporary medical implants has attracted considerable research interest as they do not require a second surgical operation for removal after the healing process is completed. However, magnesium (Mg) and its alloys have a degradation rate that is too high in biological environments. Therefore, it must be controlled using various strategies. In this study, an AZ31-Mg-based alloy coated with CeO2 is investigated to analyse the effect of the coating on its corrosion protection and biocompatibility. The AZ31 alloy is anodised with NaOH solution, before coating to stabilise the alloy surface. The CeO2 coating is deposited on anodised AZ31 by chemical conversion treatment. The electrochemical properties of samples are evaluated using electrochemical impedance spectroscopy and cyclic polarisation curves using Hank's solution. Structural and morphological characterisation of the samples are performed using X-ray diffraction and scanning electron microscopy–energy dispersive X-ray spectroscopy. Additionally, biocompatibility is determined by live/dead assay using MC3T3-E1 pre-osteoblasts. The preliminary results indicate that CeO2 coatings exhibit higher electrochemical properties. Additionally, an increase in the ratio of live/dead cells of the AZ31OH-CeO2 surface is detected, in contrast with AZ31, thus indicating improvement in biocompatibility upon CeO2 coating. [ABSTRACT FROM AUTHOR]

Climate change has evidenced the need to reduce carbon dioxide emissions into the atmosphere, and so for transport applications, lighter weight alloys have been studied, such as magnesium alloys. However, they are susceptible to corrosion; therefore, surface treatments have been extensively studied. In this work, the influence of argon plasma pretreatment on the surface properties of an AZ31 magnesium alloy focus on the enhancement of the reactivity of the surface, which was examined by surface analysis techniques, electrochemical techniques, and gravimetric measurements. The samples were polished and exposed to argon plasma for two minutes in order to activate the surface. Contact angle measurements revealed higher surface energy after applying the pretreatment, and atomic force microscopy showed a roughness increase, while X-Ray photoelectron spectroscopy showed a chemical change on the surface, where after pretreatment the oxygen species increased. Electrochemical measurements showed that surface pretreatment does not affect the corrosion mechanism of the alloy, while electrochemical impedance spectroscopy reveals an increase in the original thickness of the surface film. This increase is likely associated with the high reactivity that the plasma pretreatment confers to the surface of the AZ31 alloy, affecting the extent of oxide formation and, consequently, the increase in its protection capacity. The weight loss measurements support the effect of the plasma pretreatment on the oxide thickness since the corrosion rate of the pretreated AZ31 specimens was lower than that of those that did not receive the surface pretreatment. [ABSTRACT FROM AUTHOR]

In this paper, a Whale Optimization Algorithm (WOA) is proposed for the optimization of tribological parameters of AZ31-SiC metal matrix composite. Experiments were carried out by the surface of pin with the different loads of 10, 20, 30 N, velocities of 0.5, 1.0, 1.5 m s−1 and sliding distances of 500 m, 750 m, 1000 m respectively for optimization. The equations derived from the regression analysis are considered as objective functions to find the optimal parameters of wear and coefficients of friction (COF) using WOA. Considering these objective functions, the WOA is used to optimize the tribological parameters. The optimized parameters obtained from the WOA are compared with the parameters derived from PSO, DE, FFA and experimental results. The optimum wear values obtained from WOA, PSO, DE, FFA and experiment results are 3.55, 3.63, 3.60, 3.57 and 3.77 mg respectively. The optimum values of COF obtained from WOA, PSO, DE, FFA and experiment results are 0.311, 0.313, 0.314, 0.312, and 0.33 respectively. The optimum wear values obtained from WOA, PSO, DE and FFA are 6.01, 3.89, 4.69, 5.48% lower than the experimental value. The optimum COF values obtained from WOA, PSO, DE and FFA are 5.76, 5.15, 4.85, 5.45% lower than the experimental value. It is evidence from the results that WOA has provided the best wear and COF values for AZ31-SiC metal matrix composite when compared to other methods. This proposed method reduces the time and effort of the manufacturer to use the composite material in an application with the optimum operating condition for more life. The microstructural SEM micrographs reveal the distribution of reinforcement in the composite. The SEM micrographs of worn out surfaces present various wear mechanisms of the composites under variety of operating conditions. [ABSTRACT FROM AUTHOR]

Copyright of Acta Materiae Compositae Sinica is the property of Acta Materiea Compositae Sinica Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Gazi Üniversitesi Fen Bilimleri Dergisi Part C: Tasarım ve Teknoloji is the property of Gazi University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

There have been remarkable improvements in the research field of magnesium over the last few decades, especially in the magnesium metal matrix composite in which micro and nanoparticles are used as reinforcement. The dispersion phase of nanoparticles shows a better microstructural morphology than pure magnesium. The magnesium metal matrix nanocomposite shows improved strength with a balance of plasticity as compared to the traditional magnesium metal matrix composite. In this research, Nb2O5 (0 wt.%, 3 wt.%, and 6 wt.%) nanoparticles were used to reinforce AZ31 with the stir casting method, followed by heat treatment, and finally, an investigation was conducted using microstructural analysis. Factors such as the degree of crystallinity, crystallite size, and dislocation density are affected by the concentration of Nb2O5 and heat treatment. With the compositional increase in Nb2O5 weight percentage, the grain size decreases up to 3% Nb2O5 and then increases gradually. The SEM image analysis showed a grain size reduction of up to 3% Nb2O5 and fracture morphology changed from basal slip to a mixture of basal slip and adiabatic shear band. [ABSTRACT FROM AUTHOR]

The microstructural and mechanical behavior of a typical HCP material (AZ31 Mg-alloy) during friction stir welding was studied comprehensively for various sets of parameters. EBSD, SEM, XRD and optical microscopy have been used to characterize the microstructural properties of the welded samples, whereas tensile, microhardness and bending tests have been performed for mechanical behavior. The results showed that a large number of twins and second-phase particles (Mg17Al12 and Mg2Si) were induced. The tendency of intermetallic compounds (IMCs) formations, where both orientations of grain and grain boundaries favored its locations. The localized stress state governed the texture variation during the tension test and it was well described by EBSD analysis in terms of the assumed welding temperature. The average grain size in the stirred zone was obtained 15, 13 and 9 µm which were reduced by 32, 41 and 59%, respectively, with increasing travel speed meanwhile, in thermo-mechanically affected zone grain size was found to be 19.6, 18.2 and 13.2 µm which were reduced by 11, 17 and 40%, respectively. The maximum and minimum bending stress was achieved as 320 and 304 MPa and the corresponding bending angle was 41° and 38°, respectively, for the lowest and highest heat input conditions. All the joints fractured in HAZ-base metal regions with the lowest hardness. The weld strength was improved with travel speed due to reduced recrystallized grains in stirred zone at lower heat input. [ABSTRACT FROM AUTHOR]

Magnesium (Mg)-based alloys are biodegradable metallic biomaterials that show promise in minimizing the risks of permanent metallic implants. However, their clinical applications are restricted due to their rapid in vivo degradation and low surface hemocompatibilities. Surface modifications are critically important for controlling the corrosion rates of Mg-based alloys and improving their hemocompatibilities. In the present study, two heparinization methods were developed to simultaneously increase the corrosion resistance and hemocompatibility of the AZ31 Mg alloy. In the first method, the surface of the AZ31 alloy was modified by alkali–heat treatment and then aminolyzed by 3-amino propyltriethoxy silane (APTES), a self-assembly molecule, and heparin was grafted onto the aminolyzed surface. In the second method, before heparinization, polyamidoamine dendrimers (PAMAM4-4) were grafted onto the aminolyzed surface with APTES to increase the number of surface functional groups, and heparinization was subsequently performed. The presence of a peak with a wavelength of about 1560 cm−1 in the FTIR spectrum for the sample modified with APTES and dendrimers indicated aminolysis of the surface. The results indicated that the corrosion resistance of the Mg alloy was significantly improved as a result of the formation of a passive layer following the alkali–heat treatment. The results obtained from a potentiodynamic polarization (PDP) test showed that the corrosion current in the uncoated sample decreased from 25 µA to 3.7 µA in the alkali–heat-treated sample. The corrosion current density was reduced by 14 and 50 times in samples treated with the self-assembly molecules, APTES and dendrimers, respectively. After heparinization, the clotting time for pristine Mg was greatly improved. Clotting time increased from 480 s for the pristine Mg sample to 630 s for the APTES- and heparin-modified samples and to 715 s for the PAMAM- and heparin-modified samples. Cell culture data showed a slight improvement in the cell-supporting behavior of the modified samples. [ABSTRACT FROM AUTHOR]

• AZ31 composites reinforced by bimodal size B 4 C particles with low porosity were prepared. • The microhardness of the composites was increased by enhancing the B 4 C content. • The addition of B 4 C particles resulted in a considerable decrease in the wear rate. • The lowest wear rate was obtained at high speeds and low loadings when oxidative wear was dominant. • Mechanisms of abrasion, oxidation, delamination, adhesion and plastic deformation were activated for the unreinforced and composite samples. This study investigated dry sliding wear properties of AZ31 magnesium alloy and B 4 C-reinforced AZ31 composites containing 5, 10, and 20 wt.% B 4 C with bimodal sizes under different loadings (10–80 N) at various sliding speeds (0.1–1 m/s) via the pin-on-disc configuration. Microhardness evaluations showed that when the distribution of B 4 C particles was uniform the hardness of the composites increased by enhancing the reinforcement content. The unreinforced alloy and the composite samples were examined to determine the wear mechanism maps and identify the dominant wear mechanisms in each wear condition and reinforcement content. For this purpose, wear rates and friction coefficients were recorded during the wear tests and worn surfaces were characterized by scanning electron microscopy and energy dispersive X-ray spectrometry analyses. The determined wear mechanisms were abrasion, oxidation, delamination, adhesion, and plastic deformation as a result of thermal softening and melting. The wear evaluations revealed that the composites containing 5 and 10 wt.% B 4 C had a significantly higher wear resistance in all the conditions. However, 20 wt.% B 4 C/AZ31 composite had a lower resistance at high sliding speeds (0.5–1 m/s) and high loadings (40–80 N) in comparison with the unreinforced alloy. The highest wear resistance was obtained at high sliding speeds and low loadings with the domination of oxidative wear. [ABSTRACT FROM AUTHOR]

Superhydrophobic surfaces were prepared using a two-step method that involved the etching of AZ31 and AZ91 magnesium alloys and then modifying the etched alloys with stearic acid. Magnesium alloys etched with ZnCl2 and SnCl2 exhibited surfaces roughened with micro- and nanoscale hierarchical structures consisting of two chemically distinct regions (Zn/Zn(OH)2 or Sn/SnO2 and Mg(OH)2). An optimum etching time of ten minutes was chosen for both etchants. Superhydrophobic surfaces with the highest contact angle were prepared when stearic acid reacted with the etched alloys at 50 °C for 4 h. Stearic acid was bound as zinc stearate and magnesium stearate on Mg alloys etched with ZnCl2 and SnCl2 solutions, respectively. The superhydrophobic process on AZ31 alloys etched with ZnCl2 and SnCl2 improved the corrosion resistance in phosphate buffered saline (PBS) solution compared to bare AZ31 alloy, with the use of ZnCl2 etchant leading to better results. An improvement in the corrosion resistance of AZ91 alloy was observed when the stearic-acid-modified AZ91 alloy was etched with SnCl2. In contrast, the use of ZnCl2 etchant to pretreat AZ91 alloy resulted in a significant deterioration in corrosion properties compared to bare AZ91 alloy. The microstructure of the Mg alloy had an impact on the etching and modification process. On the basis of the findings, a characterization of the chemistry of etching magnesium alloys and the formation of superhydrophobic surfaces was proposed. Magnesium alloys were prepared with superhydrophobic surfaces, incorporating antibacterial metals, features which may increase their potential for use in medical applications. [ABSTRACT FROM AUTHOR]

The influence of temperature and strain rate on the deformation behavior of twin-roll casting AZ31 alloy has been examined as a function of stress state using notched and un-notched tensile specimens. Failure behavior during the physical tension was carried out using FEM simulations with different fracture criteria. Using a combined experimental-FEM investigation, the applicability of each fracture criterion was verified to serve the prediction for the crack initiation under multiaxial stress state. Results show that the critical fracture strain presents a clear exponential relationship with stress triaxiality and strain rate, and a linear relationship with temperature. Through the quantitative analysis of the relationship, a mathematical model can be well established. After comparison and verification, the fracture model can accurately predict the forming limit during the plastic deformation of twin-roll casted AZ31 magnesium alloy under complex stress state, and the classical Cockcroft & Latham criterion is the most suitable criterion for predicting the related crack initiation.

Magnesium (Mg) alloy is an engineering material with tremendous application potential in fields such as transportation, aerospace, electronic instruments, and biomaterials. Nonetheless, the poor abrasion and corrosion resistance hinder the further application of Mg alloy in the field of industrial manufacturing. Solid - state thermal diffusion (SSTD) is regarded as an strategy for creating intermetallic thermal diffusion layers (TDLs) on the surface of Mg alloy, providing protection against wear and corrosion. However, traditional SSTD is a high - temperatures and time - consuming heat treatment process. During the process, Mg alloy may undergo grain coarsening and phase transformations, leading to a degradation in mechanical properties. Additionally, the long - term high - temperature heat treatment will inevitably increase energy consumption and production cost. The present study introduces a solid - state pressure - assisted thermal diffusion (SSPTD) process with the goal of efficiently fabricating Mg Zn intermetallic TDLs on the surface of AZ31 alloy at relatively lower temperatures. As a result, Mg Zn intermetallic TDLs with an outer diffusion layer (ODL) and an internal diffusion layer (IDL) were successfully fabricated on the AZ31 alloy at the average fabrication rate (AFR) of 0.6–3 × 103 μm/h. When the SSTPD treatment was conducted at 360 °C for 60 min under 10 MPa, the surface microhardness of the sample was increased by up to 3.6 times compared to that of the AZ31 alloy, and the corrosion current was reduced by about 74 %. However, the decline in the microhardness and corrosion resistance took place when the sample was subjected to the SSPTD treatment under the condition of higher temperature and pressure (e.g., 400 °C@30 MPa). The degradation in performance was primarily attributed to the increased formation of α - Mg phases and phase transition defects (e.g., cracks and shrinkage cavities) within the TDLs during the SSPTD treatment. • Developed a rapid process for fabricating TDLs on the surface of AZ31 alloy. • Clarified the formation mechanism for Mg Zn intermetallic TDLs. • SSPTD was used to harden surface and improve corrosion resistance of AZ31 alloy. [ABSTRACT FROM AUTHOR]

The graphene nano-platelets (GNPs) reinforced AZ31 alloy composites were fabricated by friction stir processing (FSP) with three multi-pass and high rotation speed. The AZ31/2.14 vol% GNPs and AZ31/6.43 vol% GNPs composites were designed. The fine microstructure and uniform dispersion of GNPs were observed in the AZ31/GNPs composites. The hardness and tensile properties were enhanced after three cumulative FSP passes. This was attributed to grain refinement and strengthening effects of GNPs. The corrosion resistance of the AZ31/GNPs composites was improved due grain refinement, distribution of β-Al12Mg17 phase and anti-corrosion effect of GNPs. The tensile properties and corrosion resistance of the AZ31/6.43 vol% GNPs composite increased with increasing the volume fraction of the GNPs.

In the present work, AZ31 alloy is processed by WEDM process. The input machining variables of WEDM are designed according to Box-Behnken Design (BBD) of response surface methodology (RSM). The input machining variables considered in the present research are servo feed (SF), servo voltage (SV), pulse on-time (Ton), and pulse off-time (Toff), while the response characteristics evaluated in the present work are material removal rate (MRR), microhardness (MH), average surface roughness (Ra), and mean roughness depth (Rz). The analysis for each response is made with analysis of variance (ANOVA). The empirical models developed for each response are further utilized to get the Pareto fronts along various mutually conflicting process responses using improved multiobjective grey wolf optimization algorithm (MOGWO). In the present research, Levy flight algorithm has been used to improve the efficiency of MOGWO. It has been observed that the implemented multiple objective optimization approach is able to detect the uniformly distributed Pareto fronts very efficiently. The results obtained through the improved MOGWO are further validated through confirmation experiments which show a good agreement to the predicted results. The morphology of the machined surface is also evaluated using scanning electron microscopy, which depicts the microcracks, globules, micropores, and lumps. [ABSTRACT FROM AUTHOR]

Grain refinement is an important technique to improve the mechanical properties of metal materials. In this study, a novel technique (in-situ oxidation process) was proposed. It successfully refined grain and improved the mechanical properties of AZ31 alloy. The effect of different melt treatment process on AZ31 alloy was comparatively studied. For the in-situ oxidation process, effects of flow of O2/Ar mixed gas and the inoculating temperature on grain size were investigated. The results showed that in-situ oxidation process caused an available grain refinement of AZ31 alloy, whereas the only oxidation or the only stirring processes was invalid for grain refinement. After being treated by in-situ oxidation process with an O2/Ar mixed gas flow of 10/100 ml/min, average grain size of AZ31 alloy decreased from 1146 to 554 μm. There existed an effective grain refinement only when O2 gas flow ranges from 5 to 10 ml/min. Oxides (MgO and MgAl2O4) were found in the in-situ oxidation process refined AZ31 alloy. E2EM calculation results indicated that MgO and MgAl2O4 possess a high nucleating potency for α-Mg grain. Measured cooling curves showed that the initial nucleation undercooling declined and the nucleation process ended early. Hence, grain refinement of AZ31 alloy by in-situ oxidation process was attributed to the heterogeneous nucleation of α-Mg grain on MgO and MgAl2O4.

The use of bioabsorbable metals as temporary medical implants has attracted considerable research interest as they do not require a second surgical operation for removal after the healing process is completed. However, magnesium (Mg) and its alloys have a degradation rate that is too high in biological environments. Therefore, it must be controlled using various strategies. In this study, an AZ31-Mg-based alloy coated with CeO2 is investigated to analyse the effect of the coating on its corrosion protection and biocompatibility. The AZ31 alloy is anodised with NaOH solution, before coating to stabilise the alloy surface. The CeO2 coating is deposited on anodised AZ31 by chemical conversion treatment. The electrochemical properties of samples are evaluated using electrochemical impedance spectroscopy and cyclic polarisation curves using Hank’s solution. Structural and morphological characterisation of the samples are performed using X-ray diffraction and scanning electron microscopy–energy dispersive X-ray spectroscopy. Additionally, biocompatibility is determined by live/dead assay using MC3T3-E1 pre-osteoblasts. The preliminary results indicate that CeO2 coatings exhibit higher electrochemical properties. Additionally, an increase in the ratio of live/dead cells of the AZ31OH-CeO2 surface is detected, in contrast with AZ31, thus indicating improvement in biocompatibility upon CeO2 coating.

Climate change has evidenced the need to reduce carbon dioxide emissions into the atmosphere, and so for transport applications, lighter weight alloys have been studied, such as magnesium alloys. However, they are susceptible to corrosion; therefore, surface treatments have been extensively studied. In this work, the influence of argon plasma pretreatment on the surface properties of an AZ31 magnesium alloy focus on the enhancement of the reactivity of the surface, which was examined by surface analysis techniques, electrochemical techniques, and gravimetric measurements. The samples were polished and exposed to argon plasma for two minutes in order to activate the surface. Contact angle measurements revealed higher surface energy after applying the pretreatment, and atomic force microscopy showed a roughness increase, while X-Ray photoelectron spectroscopy showed a chemical change on the surface, where after pretreatment the oxygen species increased. Electrochemical measurements showed that surface pretreatment does not affect the corrosion mechanism of the alloy, while electrochemical impedance spectroscopy reveals an increase in the original thickness of the surface film. This increase is likely associated with the high reactivity that the plasma pretreatment confers to the surface of the AZ31 alloy, affecting the extent of oxide formation and, consequently, the increase in its protection capacity. The weight loss measurements support the effect of the plasma pretreatment on the oxide thickness since the corrosion rate of the pretreated AZ31 specimens was lower than that of those that did not receive the surface pretreatment.

In the present study, a dual composite coating consisting of an anodized layer as the inner layer and PCLF (polycaprolactone fumarate)/silicon- and magnesium-codoped fluorapatite (Si-Mg-FA) nanocomposite as the outer layer was fabricated on AZ31 Mg alloy. The thickness of the PCLF/(Si-Mg-FA) nanocomposite coating is 9.72 μm, with the Si-Mg-FA nanoparticles being well distributed in the PCLF matrix. Electrochemical measurements showed that AZ31 Mg alloy with the anodized PCLF/Si-Mg-FA coating has a low corrosion current density (5.137 × 10–6 A/cm2), providing a sufficient protection (Rp = 5888.72 Ω cm2) for Mg alloys. Immersion tests in a simulated body fluid showed that cauliflower-like/cloudy apatite forms on AZ31 Mg alloy with the anodized PCLF/Si-Mg-FA coating and governs good bioactivity. Osteosarcoma cells adhere well to the surface of the coating. Surface modification by the anodized PCLF/Si-Mg-FA coating can be a suitable method for controlling the corrosion degradation and increasing the bioactivity and cell attachment of AZ31 Mg alloy for implant applications. [ABSTRACT FROM AUTHOR]

In this study, graphene was incorporated into a micro-arc oxidation coating to improve the wear and corrosion resistance of AZ31 alloy. For this purpose, the different concentration of graphene particles was used as 0 g/l, 0.5, 1, and 2 g/l. The wear tests were performed under loads of 2, 4, and 8 N. The composition and morphology of the coatings were investigated by scanning electron microscopy, X-ray diffraction and Fourier transform infrared spectroscopy. The coating thickness increased with increasing graphene concentration. To evaluate the corrosion performance of the coatings, potentiodynamic polarization, and electrochemical impedance spectroscopy tests were performed after immersed samples for 0.5, 16, and 32 h. The wear test results show that wear rates significantly decreases with increasing graphene concentration. Corrosion tests showed that polarization resistance increased and corrosion current density decreased for the coatings with the graphene addition compared to substrate material. [ABSTRACT FROM AUTHOR]

AZ31 alloy has excellent properties like ultra-low density, good energy absorption, and high damping performance but has poor corrosion resistance. The influence of media pH on the corrosion of AZ31 alloy in chloride and sulphate media was investigated using such electrochemical techniques as potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). The tests were carried out by varying pH in different concentrations (0.05–0.25M) of the media. The surface morphologies and surface compositions of the corroded alloy surfaces were analyzed using scanning electron microscopy and energy-dispersive X-ray spectroscopy, respectively. Conclusively, the recorded results reflect a trend of a higher corrosion rate at higher concentrations of the media; and an increase in the corrosion rate on decreasing the pH of the media. In the studied pH range, the alloy showed a higher corrosion resistance at pH 11 and a lower corrosion resistance at pH 3. [ABSTRACT FROM AUTHOR]

This article presents the texture development of magnesium AZ31 alloy in the accumulative roll bonded (ARB) AZ31/AZ31 multilayer and AZ31/AA5086 laminate composite. The comparative study demonstrates that the texture evolution in AZ31 in a multilayer system is strongly influenced by the interfaces. A typical basal texture of AZ31 has been observed in AZ31/AZ31 multilayer with texture intensity increased with the rolling deformation. Presence of AZ31/AA5086 interface in the laminate composite leads to a tilted basal texture along the rolling direction (RD) in AZ31 alloy. The texture intensity of composite increased initially with rolling reduction and weakened at the higher rolling strain. Weakening of texture in AZ31 during the laminate processing at higher strain has been attributed to the development of wavy interfaces in AZ31/AA5086 laminate.

Anodized AZ31 Magnesium Alloys was synthesized via electrodeposition processes. The aim of this work was to determine the mechanical and tribological response of the anodized AZ31 Magnesium alloy with different current densities immersed under cement concrete paste with different solidification times. The samples of the anodized alloy were characterized by microindentation so, the mechanical properties (micro-hardness) was increased by 32 % when the magnesium alloy was anodized with a current density of 25 mA/cm2, in this sense the friction coefficient between the anodized AZ31 magnesium (MgO) obtained with the highest current density and the metallic AZ31 alloy exhibited a reduction of 54.5 %. The scratch test and wear rate (abrasive sliding of cement concrete) show an increase in the critical load and a reduction of weight loss as a function of the applied current density around of 49 % and 92.3 %, respectively. Scanning electron microscopy was performed to analyze morphological surface changes on the anodized AZ31 alloy after tribological tests. The tribological behavior of the anodized AZ31/MgO system indicates that the AZ31/MgO coatings can have a promising future in applications for the civil construction industry.