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SiCp/Al-Fe-V-Si composites exhibit complex deformation behaviors at both room and high temperatures because of the presence of SiC reinforcement particles and numerous fine dispersed Al12(Fe, V)3Si heat-resistant phases. In this work, an artificial neural network (ANN) constitutive model was established to study the deformation behavior of SiCp/Al-7.75Fe-1.04V-1.95Si composites over a wide temperature range based on uniaxial compression. Then, microstructural observation, finite element analysis, and processing maps were utilized to investigate the plastic workability. The results showed that the ANN model fit the experimental stress–strain curves with high accuracy, achieving an R2 value of 0.999. The ANN model was embedded into finite element software to study plastic deformation behaviors, which indicated that this model could accurately compute the plastic and mechanical response during the compressing process. Finally, a thermomechanical processing diagram was developed, revealing that the optimal processing parameters of the SiCp/Al-7.75Fe-1.04V-1.95Si composites were a deformation temperature of 450–500 °C and a deformation rate of 0.1–0.2 s−1. [ABSTRACT FROM AUTHOR]

The present study prepared 7075Al composites reinforced with vapor-phase-grown carbon nanofibers (VGCNFs) using the spark plasma sintering (SPS) method. Constitutive equations of the composites were calculated, and thermal processing maps were constructed by performing thermal compression tests on the VGCNF/7075Al composites at deformation temperatures ranging from 300 to 450 °C and strain rates from 0.01 to 1 s−1. This study analyzed the microstructural evolution of the VGCNF/7075Al composites during the thermomechanical processing. The experimental results demonstrated that dynamic recrystallization (DRX) primarily governed the softening mechanism of VGCNF/7075Al composites during thermomechanical processing. At high strain rates, a combination of dynamic recovery (DRV) and DRX contributed to the softening behavior. The incorporation of VGCNFs results in higher dislocation density and a larger orientation deviation within the 7075Al matrix during the thermomechanical deformation process, providing stored energy that facilitated DRX. The activation energy for deformation of VGCNF/7075Al composites was 175.98 kJ/mol. The constitutive equation of the flow stress showed that a hyperbolic sinusoidal form could effectively describe the relationship between flow stress, strain, strain rate, and temperature of VGCNF/7075Al composites. The optimal thermomechanical deformation parameters for VGCNF/7075Al composites were 400–450 °C and 0.01–0.1 s−1 when the strain ranged from 0.05 to 0.15. For strains between 0.25 and 0.35, the optimal thermomechanical parameters were 380–430 °C and 0.01–1 s−1. [ABSTRACT FROM AUTHOR]

This study aimed to enhance the mechanical and microstructural properties of AA 7075-T6 aluminum alloy by incorporating zeolite powder using friction stir processing (FSP). The methodology involved preparing AA 7075-T6 plates with predrilled holes for zeolite powder insertion, followed by FSP with optimized parameters (650 rpm rotational speed and 12 mm/min traverse speed). Microstructural analysis was conducted using scanning electron microscopy, and mechanical properties were evaluated through tensile and hardness tests. The results demonstrated significant improvements in tensile strength, hardness, and elongation due to the fine grain structure and uniform distribution of zeolite particles in the weld Nugget zone. The optimized FSP parameters enhanced mechanical performance, making the zeolite-reinforced AA 7075-T6 alloy suitable for high-stress applications in aerospace and automotive industries. This study confirms the potential of zeolite reinforcement in improving the durability and reliability of aluminum alloys. [ABSTRACT FROM AUTHOR]

The effects of different solution temperatures on the microstructure and corrosion resistance of graphene nanoplatelets reinforced A380 (A380-GNPs) composites were investigated. The results show that the grain size of the composites was significantly refined by adding 0.9 wt% GNPs, and most of the Si phases in the A380-0.9 GNPs composite after solution treatment at 505 °C were spheroidal. Energy dispersive spectroscopy analysis indicated that most of the Al2Cu phases have been dissolved into the matrix. The hardness of the 505 °C solution treated composites increased by 28.8% compared to the A380-0.9 GNPs composites. Immersion corrosion tests revealed that the corrosion rate of the 505 °C solution-treated A380-0.9 GNPs composites (46.76 μg cm−2 d−1) was 24.9% lower than that of the non-solution-treated (58.41 μg cm−2 d−1). Electrochemical analyses showed that the corrosion voltage of the 505 °C solution-treated composites (− 507.41 mV) was 7.4% higher than that of the non-solution-treated (− 548.76 mV). The 505 °C solution-treated A380-0.9 GNPs composites had a high surface-area ratio between the anodic phases (α-Al) and the cathodic phases (Al2Cu, Si), and the anodic corrosion current densities were relatively weak, which resulted in the best corrosion resistance. The refinement and uniform distribution of cathodic phases, such as Al2Cu and eutectic Si, inhibit the occurrence of micro-galvanic corrosion and also reduce the corrosion rate of the composites. [ABSTRACT FROM AUTHOR]

The present work aims to elucidate the mechanism of microstructural evolution in different regions of nano-SiC particles reinforced aluminum matrix composites prepared by friction stir processing (FSP) on its electrochemical behavior. Electron backscatter diffraction technique (EBSD) and transmission electron microscopy (TEM) were employed to characterize the microstructure evolution of stir zone (SZ), advancing side thermomechanically affected zone (AS-TMAZ), retreating side thermomechanically affected zone (RS-TMAZ) and base metal (BM). The electrochemical behaviors of the above zones were investigated using electrochemical tests. A homogeneous and fine microstructure is formed in SZ, not only the nano-SiC is homogeneously distributed within the grains with an average grain size of 3.5 μm, but also the recrystallized grains account for the highest percentage of 85 %. The potentiodynamic polarization curve indicates that the corrosion current densities of the BM, RS-TMAZ, AS-TMAZ and SZ are 0.89, 0.39, 0.85 and 0.36 μA/cm2, respectively, while the polarization impedances are 33.40, 51.42, 48.72 and 73.79 kΩ cm2, respectively. Combining the Nyquist and Bode plots analysis, the optimal electrochemical corrosion resistance is in SZ. The fine and homogeneous recrystallized grains in SZ significantly improve its electrochemical corrosion resistance. This is mainly ascribed to the increase in crystal defects as a result of the increase in grain boundaries, elevating the electron scattering. Simultaneously, the increase in high-energy state grain boundaries is beneficial to the rapid formation of a thicker passivation film. [ABSTRACT FROM AUTHOR]

Aluminum matrix composites reinforced with ceramic particles are widely used in parts and components operating under severe abrasive friction and wear conditions. This work investigates the effect of the particle size and the amount of B4C and SiC reinforcements ranging from 0 to 25 wt % in the initial powder mixture on the microstructure, micromechanical properties, and abrasive wear resistance of aluminum matrix composites. It is shown that B4C and SiC reinforcement particles contribute to the refinement of the aluminum matrix. Micromechanical properties determined by instrumented microindentation indicate that the hardness of the composites exceeds the hardness of sintered aluminum, and Al–25% SiC composite has the highest mechanical load resistance compared to other composites studied. Pin-on-plate wear tests of samples sliding against fixed electrocorundum grains revealed the greatest abrasive wear resistance of Al–25% SiC and Al–12.5% В4С–12.5% SiC composites. The minimum resistance was observed for Al–25% B4C. These materials demonstrate adhesive and abrasive wear behavior with the formation of characteristic wear grooves and tear pits. [ABSTRACT FROM AUTHOR]

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In the present study, the densification behavior, microstructural evolution, mechanical properties, and friction behavior of a TiB2/Al8SiCu composite and Al8SiCu alloy manufactured by laser powder-bed fusion (PBF-LB) were systematically investigated. The results confirm that the addition of in situ TiB2 particles into Al8SiCu alloys reduce the volumetric energy density required for a high-density TiB2/Al8SiCu composite. The TiB2 particles promoted a transformation of columnar to equiaxed crystals and the formation of high-angle grain boundaries. The grains on the vertical direction of the PBF-LBed TiB2/Al8SiCu composite were much finer than those of the PBF-LBed Al8SiCu alloy. The addition of TiB2 promoted the grain refinement of the Al8SiCu alloy, of which the average grain size decreased from 15.31 μm to 7.34 μm. The yield strength (YS), ultimate tensile strength (UTS), and elongation (El) of the PBF-LBed Al8SiCu alloy were 296 ± 6 MPa, 517 ± 6 MPa, and 11.7 ± 1.0%, respectively. The PBF-LBed TiB2/Al8SiCu composite achieved a balance between strength and ductility with a yield strength of 328 ± 8 MPa, an ultimate tensile strength of 541 ± 3 MPa, and an elongation of 9.1 ± 0.7%. The increase in strength mainly resulted from grain boundary strengthening, dislocation strengthening, load-bearing strengthening, solid-solution strengthening, and Orowan strengthening, of which the dislocation strengthening and Orowan strengthening were critical. The enhanced hardness associated with the grain refinement and the formation of the in situ TiB2 particles also led to an enhanced tribological performance, of which reductions in the average friction coefficient from 0.655 to 0.580 and wear rate from 1.76 × 10−3 mm3/Nm to 1.38 × 10−3 mm3/Nm were found. [ABSTRACT FROM AUTHOR]

Taking TiCp/Al-5Cu-1.9Mg-0.9Mn composite materials reinforced with 0.27%（volume fraction）TiC particles as the matrix， the effects of different Sm element contents on the microstructure and mechanical properties of the composite material were investigated. The results show that the addition of the Sm element significantly refines the dendritic microstructure and facilitates the dissolution of the second phase during the solid solution treatment. Consequently， an increase in the density of precipitated phases， including T-Al20Cu2Mn3 and S'-Al2CuMg， was observed in the aged microstructure. When the Sm element content is high （0.3%， mass fraction， the same below）， the microstructure exhibits blocky insoluble rare earth-containing compounds. With the addition of the Sm， the composite materials show a gradual increase in yield strength at both room temperature and 250 ℃. However， it will cause a decrease in plasticity. When the Sm element content is 0.3%， the yield strength at room temperature increases from 246 MPa to 310 MPa， and the yield strength at 250 ℃ increases from 191 MPa to 220 MPa. The analysis suggests that the increase in strength is attributed to the microstructural refinement and the increased density of precipitated phases induced by Sm. Conversely， the reduction in plasticity is attributed to the presence of coarse blocky insoluble rare earth compounds cutting through the matrix， leading to the easy generation of crack sources.

In this study, micro-nano hybrid SiCp/7075Al composites were successfully prepared for the first time by ultrasonic-assisted semi-solid stirring casting method. The effects of micro-nano hybrid SiCp on the microstructure and mechanical properties of 7075 Al were studied. The results show that the distribution of SiCnp and micron SiCp in the microstructure was uniform. During the extrusion process, most of the micron SiCp were subjected to significant load and broken, which increased the contact area with the matrix and promoted the interface bonding. In addition, the enhanced interfacial interaction promoted the formation of MgAl2O4 phase, which significantly improved the mechanical properties. SiCnp not only had a significant effect on grain refinement, but also promoted the enrichment of Cu, accelerated the formation of GP zone, and promoted the formation of more nano-MgZn2 precipitates. The yield strength and the elastic modulus of micro-nano hybrid SiCp/7075 Al composites reached 450 MPa and 94 GPa, respectively. The synergistic effect of SiCnp and micron SiCp could produce composite strengthening effects such as load transfer strengthening, thermal mismatch strengthening and Orowan strengthening. Moreover, a large number of dislocation pile-ups were observed near the interface between micron and nano SiCp and Al matrix. This leaded to a higher work hardening rate of the composites as the particle content increases. The higher work hardening rate enhanced the strain hardening ability of the material during plastic deformation, thereby significantly improving the tensile strength and elongation of the material.

This work investigated the Vickers hardness and compressive properties of 0–30 % ZrMgMo 3 O 12p /2024Al composites with controlled thermal expansion. The composites exhibited superior Vickers hardness and compressive properties, highly dependent on the ZrMgMo 3 O 12 content. Under identical preparation conditions, an increase in ZrMgMo 3 O 12 content allows for adjusting the Vickers hardness from 163 to 280 HV and the compressive yield strength from 330 to 702 MPa. Additionally, the 5 % and 10 % ZrMgMo 3 O 12 composites exhibited 23 % and 8 % compressive strains, respectively. The Orowan strengthening effect of the ZrMgMo 3 O 12 particles and the thermal mismatch stress at the particle-matrix interface were identified as the key strengthening mechanisms for the composites. However, excessive stress can lead to interfacial debonding and composite failure. Agglomeration of the ZrMgMo 3 O 12 particles was observed beyond 10 % content. At 30 %, the thermal mismatch stress exceeded the binding strength, causing interfacial debonding and composite failure. The controlled mechanical properties of the 0–30 % ZrMgMo 3 O 12p /2024Al composites indicate a promising potential for application in the aerospace and automotive industries and electronics and optical instruments sectors. [ABSTRACT FROM AUTHOR]

Abstract This study introduces an innovative approach to fabricate aluminum matrix composites strengthened with biochar, derived from renewable biomass sources. A systematic investigation of varying biochar weight percentages (0, 2.5, 5, 7.5, and 10 wt%) reveals substantial improvements in mechanical properties and corrosion resistance. Mechanical assessments, including compressive strength and hardness, demonstrate a significant enhancement in mechanical strength with biochar incorporation. In this study, it was discovered that the composite with 7.5 wt% biochar exhibits an optimal balance, displaying an 8.83% increase in compressive strength and a 15.15% rise in hardness compared to the base aluminum matrix. The study further evaluates corrosion behavior through electrochemical analyses and immersion tests in 3.5% NaCl corrosive environments, highlighting the superior corrosion resistance of biochar-reinforced composites. Corrosion rates decrease by 73% in the composite with 10 wt% biochar for the 24 h immersion time, affirming its protective barrier against corrosive agents. This research provides quantitative insights into tailoring mechanical and corrosion properties in aluminum matrix composites through biochar reinforcement, offering a promising avenue for sustainable material development. The resulting materials exhibit not only an 8.83% increase in mechanical strength but also a 73% reduction in corrosion rates, offering valuable uses in industries that need strong, eco-friendly solutions.

Joint units processed by milling and grinding, which varied in surface processing marks, were used in solid-state bonding experiments to study how these marks affect the healing behavior of CNTs/Al composite bonding interfaces. The results showed that these machining marks significantly impact interface healing, as evidenced by the shapes and sizes of the interface oxides after bonding, and by the magnitude of forces and displacements transmitted from macroscopic deformations to microscopic interfaces. The healing process involves gap closure, oxide layer fracturing, fresh metal extrusion, and oxide dissolution. CNTs and their byproduct Al4C3 play a crucial role in this process. They pin the grain boundaries and interfaces, providing multiple deformation anchorage points, which not only cause the interface oxide layer to fracture into fine oxide fragments but also effectively suppress grain coarsening at high temperatures. Their dispersed distribution in the Al matrix offers massive phase boundaries. Combined with the high-density grain boundaries in the ultrafine CNTs/Al composites, this facilitates atomic short-circuit diffusion, thereby accelerating the dissolution of oxide inclusions at the interface. Enhancing the precision of surface machining can effectively reduce oxide inclusions at the bonding interface and promote interface healing, while redundant processes should be avoided. The strength of the solid-state bonding joints under precision grinding has reached 376 MPa, exceeding 90% of the raw material strength, achieving high-efficiency seamless bonding.

This study introduces an innovative approach to fabricate aluminum matrix composites strengthened with biochar, derived from renewable biomass sources. A systematic investigation of varying biochar weight percentages (0, 2.5, 5, 7.5, and 10 wt%) reveals substantial improvements in mechanical properties and corrosion resistance. Mechanical assessments, including compressive strength and hardness, demonstrate a significant enhancement in mechanical strength with biochar incorporation. In this study, it was discovered that the composite with 7.5 wt% biochar exhibits an optimal balance, displaying an 8.83% increase in compressive strength and a 15.15% rise in hardness compared to the base aluminum matrix. The study further evaluates corrosion behavior through electrochemical analyses and immersion tests in 3.5% NaCl corrosive environments, highlighting the superior corrosion resistance of biochar-reinforced composites. Corrosion rates decrease by 73% in the composite with 10 wt% biochar for the 24 h immersion time, affirming its protective barrier against corrosive agents. This research provides quantitative insights into tailoring mechanical and corrosion properties in aluminum matrix composites through biochar reinforcement, offering a promising avenue for sustainable material development. The resulting materials exhibit not only an 8.83% increase in mechanical strength but also a 73% reduction in corrosion rates, offering valuable uses in industries that need strong, eco-friendly solutions. [ABSTRACT FROM AUTHOR]

Friction stir welding (FSW) is a remarkable green solid-state joining process and it has been proven to be capable of joining advanced materials, such as aluminum matrix composites (AMCs) with sound-quality of joints. As a result, FSW is widely used in many sectors such as aviation, automotive, marine, and structural applications. So far various researchers carried out studies on joint characteristics of FSW and reported better microstructural and mechanical properties. This review study emphasizes various joint characteristics of AMCs namely microhardness, tensile, wear, and microstructural properties of joints obtained by FSW. Also, research work carried out by several researchers in the field of FSW for joining AMCs is summarized. In addition, future trends and challenges in joining of AMCs using FSW is presented. [ABSTRACT FROM AUTHOR]

Aluminum matrix composites (AMCs) with hetero-grains exhibit high strength with good ductility. A trimodal grain structure composed of ultrafine grains (UFGs), fine grains (FGs) and coarse grains (CGs) prevents the pre-mature cracking of hetero-zone boundaries in conventional bimodal grain structures; thus, it is favored by AMCs. However, the design of the size and distribution of hetero-domains in trimodal AMCs is tough, with complicated multi-scale deformation mechanisms. This study tunes the distribution of FG domains elaborately via altering the volume fraction of FG from 10 vol.% to 60 vol.% and investigates the distribution effect of FG domains on strength–ductility synergy. The optimized 2024 Al matrix composites with 30 vol.% FG exhibited a tensile strength of over 700 MPa and an elongation of 7.5%, respectively, realizing a good combination of high strength and ductility. This work enlightens the heterostructure design with a balance between heterogeneous deformation induced (HDI) strain hardening and high-content soft phase induced strain homogenization. [ABSTRACT FROM AUTHOR]

Aging treatments are the key process to obtain satisfactory strength for 7xxxAl alloys and their composites. However, traditional single-stage (SS) aging is time-consuming to reach a peak strength condition. In this study, an efficient 120°C + 160°C two-stage (TS) aging treatment was proposed on a B4C/7A04Al composite fabricated via powder metallurgy (PM) technology, which could acquire similar peak-aging strength but only took about 15% of the time compared to traditional 120°C SS aging. The evolution of precipitation during the TS aging was investigated, as well as those of the 7A04Al alloys for comparison. In the second stage aging process, the higher aging temperature accelerated the nucleation of η′ phases inside the grains and thus increased the density of precipitates. Moreover, the short aging time limited the coarsening of precipitates and the broadening of precipitate-free zones. The above factors were beneficial for quickly obtaining satisfactory precipitation strengthening effects. The B4C/7A04Al composite exhibited slower aging kinetics than the 7A04Al alloy in the TS aging. Mg elements consumption by the chemical reaction between B impurities introduced by B4C particles and the Al matrix was considered to potentially retard the aging kinetics of the B4C/7A04Al composite. Nevertheless, the precipitation sequence was not affected. [ABSTRACT FROM AUTHOR]

The increased demand for lightweight structural materials in the transport sector has compelled researchers to develop materials with high strength and reduced structural weight, aiming to enhance vehicle performance, minimize fuel and oil consumption and reduce CO2 emissions. However, their structural weight and strength still need to be improved. Herein, an attempt has been made to fabricate aluminum-based composites reinforced with hexagonal boron nitride (h-BN: 1,3,5,7 wt%) and multi-walled carbon nanotubes (MWCNTs: 0.25, 0.5, 0.75, 1 wt%) through powder processing method. The results revealed that the 3BN/Al composite disclosed better densification (96.8%) and hardness (49 ± 1.5) among all BN/Al composites. Furthermore, the addition of 0.5 wt% CNTs to BN/Al composite significantly improved the densification (97.7%), Vickers hardness (106%) and tensile strength (189%) over pure Al. This improvement was attributed to homogeneously distributed h-BN and CNTs in the Al matrix and the formation of hard aluminum carbide (Al4C3) phase. The results demonstrate that BN/CNTs/Al composite exhibits superior mechanical strength, making them promising structural and functional materials for aerospace and automobile industries. [ABSTRACT FROM AUTHOR]

Negative thermal expansion (NTE) ceramics Sm0.85Zn0.15MnO3 (SZMO) and ZrMgMo3O12 (ZMMO) were selected to prepare Sm0.85Zn0.15MnO3-ZrMgMo3O12/Al-20Si (SZMO-ZMMO/Al-20Si) composites using ball milling and vacuum heating-press sintering processes in this study. The synergistic effect of the SZMO and ZMMO NTE ceramic reinforcements on the microstructure, mechanical properties, and coefficient of thermal expansion (CTE) of the composites was investigated. The results show that the processes of ball milling and sintering did not induce the decomposition of SZMO or ZMMO NTE ceramic reinforcements, nor did they promote a reaction between the Al-20Si matrix and SZMO or ZMMO NTE ceramic reinforcements. However, the excessive addition of SZMO and ZMMO NTE ceramics led to their aggregation within the composite. Adding a small amount of SZMO in combination with ZMMO effectively increased hardness and yield strength while reducing CTE in the Al-20Si alloy. The improvement in strength was primarily provided by SZMO, while the inhibition effect on CTE was primarily provided by ZMMO. An evaluation parameter denoted as α was proposed to evaluate the synergy effects of SZMO and ZMMO NTE ceramic reinforcements on the mechanical properties and CTE of the composites. Based on this parameter, among all composites fabricated, adding 2.5 vol% SZMO NTE ceramic and 10 vol% ZMMO NTE ceramic resulted in an optimal balance between CTE and strength for these composites with a compressive yield strength of 349.72 MPa and a CTE of 12.55 × 10−6/K, representing a significant increase in yield strength by 79.20% compared to that of Al-20Si alloy along with a notable reduction in CTE by 26.44%. [ABSTRACT FROM AUTHOR]

In recent years, the auto industry has experienced significant advancements, making research and development (R&D) of vehicle materials increasingly vital. Aluminum matrix composites (AMCs), known for their lightweight, high strength, and excellent corrosion resistance, have demonstrated substantial potential in vehicle aesthetics, interior trim, power systems, and components manufacturing. Currently, aluminum-metal composites (such as Cu and Mg) and aluminum-nonmetal composites (including Si, C, and plastics) are the primary types of AMCs used in automobiles. A thorough investigation into their preparation, process mechanisms, and performance optimization is essential for the broader application of AMCs in new vehicle models. This review summarizes and analyzes the preparation methods, wear mechanism, performance enhancement strategies, strengthening mechanism, and economic impact of AMCs, discussing key influential factors to foster the development of new AMCs. Additionally, by examining the role of aluminum compound packing films in the pouch batteries of Electric Vehicles, also explores the future potential of AMCs within the new energy power sector.

In-situ synthesized 1 wt%, 3 wt% and 5 wt%TiC/6061 nanocomposites were prepared by the reaction using Al-K2TiF6-C as starting materials. Microstructure, mechanical properties and strengthening mechanism of the nanocomposites were investigated. SEM observation illustrates the in-situ synthesized ceramic TiC particles show shape of a polygon and its average size is 60 nm. TEM results show that the interface between the Al matrix and TiC reinforcement is clear and no reaction products can be found. Grain refining can be observed in the composites, as the TiC content increased from 0 wt% to 3 wt%. However, grain coarsening appears in the 5 wt%TiC/6061 composites. As increasing the TiC content from 0 wt% to 5 wt%, the mechanical properties of the composites increase firstly and then decreases. The Vickers hardness, yield strength, tensile strength and elongation of the as-cast 3 wt%TiC/6061 composites achieve the maximum value of 80.7 HV, 135 MPa, 202 MPa and 15.3 %, respectively. Strengthening mechanisms of the TiC/6061 nanocomposites is the micromechanical strengthening mechanisms. As the TiC content increasing, CTE strengthening plays an important role.

To overcome the strength-ductility conflict in particle reinforced aluminum matrix composites (PRAMCs), a novel dual configuration strategy of microstructure was proposed in this work. The dual configuration including both heterogeneous grain structure and hybrid reinforcements was obtained by powder metallurgy, which was designed as submicron-sized SiC particles (SiCsm)/Al and micron-sized SiC particles (SiCm)/2024Al components. Representative alternating coarse grain (CG) bands containing SiCm and ultra fine grain (UFG) bands with dispersed SiCsm were revealed in microstructural characterizations. Compared to corresponding homogeneous composites with the same fraction particles, the dual configuration composite achieved simultaneous enhancement in strength and ductility and remained a comparable Young’s modulus of 98GPa, which represented 442 MPa in yield strength, 590 MPa in ultimate strength and 8.7 % in fracture elongation. The extra strength provided by hetero-deformation induced (HDI) strengthening is a potential dominant strengthening mechanism. The intrinsic toughening mechanisms primarily contribute to HDI strain hardening and enhanced dislocation accumulation capacity, while the extrinsic toughening mechanisms presumably attribute to more uniform microcrack distribution and blunting effect of CG zones on cracks. Our work provides a feasible route including ball milling and powder assembly to preparate high-modulus aluminum matrix composites for strength-ductility balance design.

In this study, a hot isostatic pressing (HIP) manufactured SiC particles (SiCp) reinforced high alloyed Al–Zn–Mg–Cu–Zr–Ti aluminum matrix composite was fabricated through ball-milling, HIP, homogenization, hot extrusion, solution treatment, and aging treatment. The results showed the presence of an interfacial reaction layer, MgAl2O4, around the SiCp, which enhanced the bonding between the particles and the matrix. The aging treatment resulted in the formation of different aging precipitates, which were featured by GP zone for T4, GP zone + η' (metastable MgZn2) + η (stable MgZn2) for T6 and GP zone + η' (metastable MgZn2) for T6I4. The composite samples of T4, T6, and T6I4 exhibited different mechanical properties. Specifically, the elastic modulus was measured as 102.9, 103.4, and 102.3 GPa, the yield strength was 685.3, 598.1, and 619.7 MPa, the ultimate tensile strength was 713.6, 618.9, and 633.3 MPa, and the elongation was 2.2%, 1.8%, and 2.8%, respectively. Furthermore, the corrosion behavior of the composite was evaluated through electrochemical, intergranular corrosion, and exfoliation corrosion. The corrosion current density was found to be 3.17 × 10−7, 4.97 × 10−7, and 3.67 × 10−7 A cm−2, the corrosion potential was measured as −0.70, −0.81, and −0.56 V, and the maximum intergranular corrosion depth was 139.9, 167.8, and 106.2 μm for T4, T6, and T6I4, respectively. The severity of exfoliation corrosion varied, with T4 showing severe pitting, T6 exhibiting moderate pitting, and T6I4 displaying slight pitting. The strengthening mechanism and load transfer strengthening of the composites were discussed in detail based on theoretical calculations, and the anti-corrosion mechanisms were also analyzed.

The 10 vol% ZrMgMo3O12/2024Al composites were fabricated using the powder metallurgy process and consolidation via vacuum hot pressing. The effects of the ball milling process and solution treatment time on the composites’ microstructure, Vickers hardness, and compressive properties were studied. Increasing the ball milling speed and extending the ball milling duration reduce the size of ZrMgMo3O12 particles, resulting in a more uniform dispersion within the aluminum matrix. Extending the solution treatment duration facilitates the dissolution of more primary Al2Cu phase into the aluminum matrix reducing the presence of coarse primary Al2Cu phase and increasing the number of fine Al2Cu precipitates formed during the aging process. The results indicated that an appropriate increase in ball milling speed, extension of ball milling duration, and solution treatment time can enhance the Vickers hardness and room temperature compressive strength of the composites. Specifically, the composites processed with a ball milling speed of 350 rpm for 6 h, a solid solution treatment at 495 °C for 24 h, and an aging treatment at 190 °C for 8 h exhibited a Vickers hardness of 277 HV and a compressive yield strength of 687 MPa, along with a compressive strain of 7.8 %.

In view of the problems of high preparation cost and low preparation efficiency of traditional powder metallurgy process, 15%(volume fraction, the same below)SiC/2009Al composite was prepared by cold isostatic pressing combined with pressureless sintering and hot extrusion process. The effect of different sintering temperatures (600, 620, 640 ℃) on microstructure and mechanical properties of 15%SiC/2009Al composite was studied. The results show that sintering at 600 ℃, the bonding between SiC and the matrix is poor, more large-size pores can be observed under the microscopic level, the density of the material is low, and the mechanical properties are poor. Sintering at a high temperature of 640 ℃, the billet produces a large amount of liquid phase, and overflows onto the surface of the billet, which causes the core alloying elements to decrease.In addition, sintering at 640 ℃ will trigger a strong interface reaction, generate more large-size brittle phase, become the source of cracks in the material fracture process, resulting in a decrease in material properties; 620 ℃ is the best sintering temperature, and more liquid phase can fill part of the pores in the billet, thereby improving the density and interfacial bonding strength of the material, and the strength and plasticity of the composite material have obtained the best values, the tensile strength and yield strength reach 505 MPa and 345 MPa, respectively, and the elongation reaches 7.2%.

Synergistic reinforcement of dual-phase particles with different sizes was always considered superior to single-phase reinforcement in composites, but there were few studies to investigate the role of each part in enhancing properties. In this work, 40 vol% (TiB2p-TiCp)/Al–Cu–Mg composites with different proportions of TiB2p and TiCp (3:1, 2:1, 1:1, 1:2 and 1:3), were fabricated by the combustion synthesis to contrast the strengthening effect of dual-phase particles from the interface stability and the characteristics of dual-phase particles. Calculated by the first principle, TiB2 (3.12 J/m2) presented better interfacial stability with Al matrix than TiC (1.61 J/m2). Under the circumstance of the same volume fraction, the composites with a higher proportion of TiB2p usually show higher yield and maximum compressive strength and effectively prevent the crack growth of composites. However, excess submicron sized TiB2p tends to produce cracks at the hexagon edge when the loads were applied and formed crack loops delaminating materials. When the TiB2p/TiCp proportion was 1:1, the plasticity and strength were beneficially balanced at the elevated temperature. Otherwise, the composite with TiB2: TiC = 3:1 possessed the best wear resistance (coefficient of friction: 0.22) at a sliding velocity of 0.32 mm/s, 30 N load) among other composites (AR12, AR11, AR21, and AR31) at 473 K, which reduced 45%, 64%, 73% and 86%, respectively. The main wear mechanism was abrasive wear when the TiB2 proportion was dominant. Submicron sized TiB2p with better interface bonding can keep the rigidity of the composites to resist the plastic flow, while TiC nanoparticles are easier to be extracted during the wear process.

In recent years, there has been tremendous growth in the use of Al matrix composites (AMCs) in various engineering applications. The aerospace and automotive industries are using more and more AMC parts. It has been widely recognized that the comprehensive properties of AMCs are significantly affected and determined by the structural design and the evolution of the microstructure of AMCs in the deformation process. Based on the current research status of the design of AMC structure and the evolution of microstructure, this paper presents a panorama of the design of the structure and the evolution of microstructure with respect to the reinforcements, the interface between Al matrix and reinforcements, and the Al matrix in AMCs, respectively. The overall properties or performance of AMCs are examined in this review, which emphasizes their advantages and limitations as compared to their traditional or unreinforced counterparts. The experimental and theoretical analysis and prediction to aid the design of the spatial distribution of reinforcements and the optimization of structural parameters, as well as the study of the evolution of microstructures, are critically analyzed, discussed, and elucidated. Finally, the research gap, the key challenges in research and the promising application potentials in future are also discussed and articulated.

We employed a novel technique combining wire and powder co-delivery to fabricate a functionally gradient material (FGM) structure consisting of Al-based composites reinforced with alternating TiC and B4C particles. The TiC content increases from the bottom up and then decreases, while the B4C content gradually increases, resulting in a continuous gradient structure. Correspondingly, the grain size of the Al matrix also changes with the variation of ceramic particles, forming a dual-gradient change trend. This FGM structure exhibits a multi-performance balance of strength, ductility, anti-wear and damping properties, making it a promising candidate for the cost-effective application in multi-performance heterostructured components.

Core-shell structured particles are potential reinforcement agents for metal matrix composites. In this work, aluminum matrix composites reinforced with core-shell structured Al35Ti15Cu10Mn20Cr20 high-entropy alloy (HEA) particles were fabricated by spark plasma sintering (SPS) and high-temperature diffusion post-treatment. Dynamic compression behavior and adiabatic shear failure mechanism in the composites were investigated by split Hopkinson pressure bar (SHPB), scanning electron microscopy and transmission electron microscopy. Results showed that the shell thickness of the core-shell particles ranged from 0.4 to 1.6 μm, which were formed by thermal diffusion between HEA core and aluminum alloy. The 30 vol% (Al35Ti15Cu10Mn20Cr20)p/2024Al composite showed a high compressive strength (594 MPa) and strain-to-failure (26.7 %) under quasi-static compression, as well as a high flow stress (602 MPa) and strain-to-failure (45.3 %) under dynamic compression, which are superior to common ceramic particles reinforced Al matrix composites. The (Al35Ti15Cu10Mn20Cr20)p/Al composites with ∼20–40 vol% core-shell HEA particles failed as bulging, 45° shearing or splitting when compressed at ∼1000-3000 s−1. Micro-damages in these composites were due to microcracks originated from the HEA core, while propagation of cracks was effectively restrained by the shell. Deformation bands and phase transformation (melting of aluminum) were both observed in the composites under dynamic loads. Chain-shaped deformation bands were formed by the fragmentation and rearrangement of the core-shell particles, instead of the recrystallized structure of metal matrix in particle-reinforced Al matrix composites reported previously. The formation of molten Al phase transformation bands was owing to shear localization and significant adiabatic temperature rise under dynamic compression.

6061 aluminum matrix composites added by 3% diamond particles (mass fraction) were prepared by laser powder bed fusion (LPBF). The microstructure, relative density, and tensile properties of the 3%diamond/6061 aluminum matrix composites were characterized and analyzed by optical microscope, scanning electron microscope, X-ray diffractometer, electronic densitometer, and electronic universal testing machine. Results show that the diamond reacts with the Al matrix, generating the needle-like Al4C3 phase, which deposits in the α-Al matrix. Those formed Al4C3 increases dislocations at the grain boundaries, enhances the materials’ strength, and delays the failure to fracture. The addition of diamond facilitates the elimination of thermal cracks, but the porous defects remain in 6061 aluminum alloys. The lower scanning speed extends the contact duration between the laser spot and the processed material, leading to the graphitization of the added diamond and the partial evaporation of the Al matrix. Thus, the internal defects exist, exhibiting the low densification of the composite (relative density 97%). The addition of diamond significantly increases the tensile strength of the LPBF formed diamond/6061 aluminum matrix composites, and the ultimate tensile strength reaches the maximum value of 244.2 MPa, the yield strength is 211.6 MPa, and the elongation is 2.1%, respectively, when the laser power is 350 W and the scanning speed is 800 mm·s−1.

SiCp/2024Al composite was prepared by semi-solid stirring casting, and the distribution of SiCp was regulated by multi-step deformation of hot extrusion and multi-direction forging (MDF). The effects of SiCp distribution on the microstructure and properties of SiCp/2024Al composite ware studied. The results show that hot extrusion deformation cause SiCp to distribute along the extrusion direction (ED). After multi-directional forging, SiCp distribution is improved significantly, and it changes from directional distribution to uniform distribution. After 1MDF, the SiCp distribution along the ED changes to disordered distribution, and the mechanical properties of the material are sharply decreased. After 3MDF, the distribution uniformity of SiCp is improved, and the mechanical properties of the material are greatly improved. When the forging passes increase to 6, the distribution uniformity of SiCp is further improved, the mechanical properties of the material decrease with the partial SiCp breaking. When the forging number is 3, the mechanical properties of the composite are optimal, with yield strength, ultimate tensile strength and elongation are 264 MPa, 387 MPa and 7%, respectively. Compared with the directionally distributed composite, the uniform distribution of SiCp effectively relieves the local stress concentration, and the matrix alloy stores more dislocation. In addition, when the distribution uniformity of SiCp is improved, the Al2Cu phase is also refined. The diffuse distribution of Al2Cu phase hinders the slip of dislocation, resulting in a uniformly distributed composite with a higher work hardening rate and internal stress. In order to study the effect of SiCp distribution on softening behavior of composites, cyclic stress relaxation experiments are carried out. In the process of stress cycling, the uniformly distributed SiCp/2024Al composites with uniform distribution of SiCp and Al2Cu phases exhibit a better stress relaxation resistance.

With the rapid development of low-temperature fields such as deep space exploration，polar scientific research，low-temperature storage and transportation，the service conditions for low-temperature structural components are becoming increasingly stringent. Therefore，low-temperature materials have gradually become a research hotspot in the world. This article mainly summarizes the low-temperature performance and related mechanisms of common structural materials such as low-temperature steel，aluminum alloy，titanium alloy，aluminum matrix composites and resin matrix composites. The effects of different crystal structures，alloy types，alloying elements and other factors on the mechanical properties of structural materials such as low temperature strength，plasticity and toughness，and the mechanism of low temperature deformation，strengthening and toughening are concluded. The application and prospect of different grades of low-temperature structural materials in different fields at home and abroad are also briefly introduced. The future research prospect of low-temperature materials is put forward.

Distinctive attributes of hybrid aluminum matrix composites enhance their industrial applications; however, reinforcement particulates complicate their machining, specifically when intricate profiles with high precision are involved due to their intended applications. This study investigates the dimensional accuracy of squeeze casted Al2024/Al2O3/W hybrid composite during wire electric discharge machining. A cone-shaped convoluted profile has been opted for machining to address the industrial needs, therefore, dimensional deviation in length, vertex angle and curvature radius of specimens have been assessed. The influence of cryogenic treatment of wire electrodes has been analyzed to control dimensional deviation in machining. Besides this, the influence of four machining variables including pulse duration, wire feed rate, wire runoff speed and wire tension on the dimensions deviations has also been investigated. The findings indicate that the pulse duration and wire tension notably influence the length error and curvature radius error. Additionally, the pulse duration and wire feed rate have been found to significantly impact the vertex angle error. The non-treated wire creates more significant craters and macro voids on the machined surface due to uneven sparking. In contrast, due to its enhanced electrical properties, the cryogenic-treated wire exhibits a comparatively refined microstructure on the machined surface, displaying fewer micro-voids and shallow craters. Comparative analysis shows that cryogenically treated wire offers 65.5 %, 35.3 % and 33.4 % reduction in length error, vertex angle error and curvature radius error than non-treated wire. The findings of this study can be helpful for the manufacturing industry for precision machining of intricate geometries.

The distribution of reinforcements and interfacial bonding state with the metal matrix are crucial factors in achieving excellent comprehensive mechanical properties for aluminum (Al) matrix composites. Normally, after heat treatment, graphene nanosheets (GNSs)/Al composites experience a significant loss of strength. Here, better performance of GNS/Al was explored with a hybrid strategy by introducing 0.9 vol.% silicon carbide nanoparticles (SiCnp) into the composite. Pre-ball milling of Al powders and 0.9 vol.% SiCnp gained Al flakes that provided a large dispersion area for 3.0 vol.% GNS during the shift speed ball milling process, leading to uniformly dispersed GNS for both as-sintered and as-extruded (0.9 vol.% SiCnp + 3.0 vol.% GNS)/Al. High-temperature heat treatment at 600 °C for 60 min was performed on the as-extruded composite, giving rise to intragranular distribution of SiCnp due to recrystallization and grain growth of the Al matrix. Meanwhile, nanoscale Al4C3, which can act as an additional reinforcing nanoparticle, was generated because of an appropriate interfacial reaction between GNS and Al. The intragranular distribution of both nanoparticles improves the Al matrix continuity of composites and plays a key role in ensuring the plasticity of composites. As a result, the work hardening ability of the heat-treated hybrid (0.9 vol.% SiCnp + 3.0 vol.% GNS)/Al composite was well improved, and the tensile elongation increased by 42.7% with little loss of the strength. The present work provides a new strategy in achieving coordination on strength–plasticity of Al matrix composites. [ABSTRACT FROM AUTHOR]

We employed a novel technique combining wire and powder co-delivery to fabricate a functionally gradient material (FGM) structure consisting of Al-based composites reinforced with alternating TiC and B4C particles. The TiC content increases from the bottom up and then decreases, while the B4C content gradually increases, resulting in a continuous gradient structure. Correspondingly, the grain size of the Al matrix also changes with the variation of ceramic particles, forming a dual-gradient change trend. This FGM structure exhibits a multi-performance balance of strength, ductility, anti-wear and damping properties, making it a promising candidate for the cost-effective application in multi-performance heterostructured components. This article reports a novel technique to manufacture FGM structures using a wire-and-powder co-delivery method. The resulting dual-gradient TiC-B4C/Al composite structure exhibits a balance of strength, ductility, anti-wear and damping. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office 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.)

Aluminum matrix composites (AMMCs) have demonstrated substantial potential in the realm of armor protection due to their favorable properties, including low density, high specific stiffness, and high specific strength. These composites are widely employed as structural components and frequently encounter high strain rate loading conditions, including explosions and penetrations during service. And it is crucial to note that under dynamic conditions, these composites exhibit distinct mechanical properties and failure mechanisms compared to static conditions. Therefore, a thorough investigation into the dynamic mechanical behavior of aluminum matrix composites and precise constitutive equations are imperative to advance their application in armor protection. This review aims to explore the mechanical properties, strengthening the mechanism and deformation damage mechanism of AMMCs under high strain rate. To facilitate a comprehensive understanding, various constitutive equations are explored, including phenomenological constitutive equations, those with physical significance, and those based on artificial neural networks. This article provides a critical review of the reported work in this field, aiming to analyze the main challenges and future development directions of aluminum matrix composites in the field of protection. [ABSTRACT FROM AUTHOR]

The manuscript presents the synthesis and dry sliding wear performance of Al7075 alloy‐based composites. Five compositions namely Al7075 alloy, Al7075+3 vol % molybdenum disulfide, Al7075+3 vol % molybdenum disulfide+3 vol % zirconium diboride, Al7075+3 vol % molybdenum disulfide+6 vol % zirconium diboride and Al7075+3 vol % molybdenum disulfide+9 vol % zirconium diboride were stir cast and characterized for hardness, x‐ray diffraction, microstructure, and tribological properties. In‐situ formed zirconium diboride particles increase the hardness of Al7075 alloy whereas molybdenum disulfide shows the opposite trend due to its self‐lubricating nature. X‐ray diffraction analysis identifies subsequent phase particles in the matrix while microstructural images exhibit the dispersion and morphology of reinforcement particles. The wear tests and friction coefficient were analyzed with variations of sliding velocity, normal load, sliding distance, and compositions. Further, the obtained wear results were also correlated with microstructure and wear surface topography. Al7075+3 vol % molybdenum disulfide composite shows the lowest coefficient of friction because of its self‐lubricating nature. Al7075+3 vol % molybdenum disulfide+9 vol % zirconium diboride hybrid composite exhibits the lowest wear rate at high velocity as well as at high load and can be potentially used in manufacturing and tribological applications. Moreover, the use of this material may lead to the minimum requirement of external toxic lubricants that make it cost‐effective and environmentally sustainable. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Materials Engineering / Cailiao Gongcheng is the property of Journal of Materials Engineering Editorial Office 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.)

In order to investigate the hot deformation behavior of an in situ 2 wt.% TiB2-reinforced 6061 Al matrix composite (hereafter labeled as TiB2/6061 Al composite), hot compression tests were conducted over the deformation temperatures of 300-500 °C and the strain rates of 0.001-10 s−1. The flow stress of the TiB2/6061 Al composite decreases with the deformation temperature increasing and strain rate decreasing during the hot compression process. The Arrhenius constitutive equation with the activation energy to be 335.6 kJ mol−1 was constructed to characterize the flow stress behavior. Hot compression can effectively eliminate the casting void defects of the studied composite and significantly improve the distribution of TiB2 particles in the composite matrix. The existence of TiB2 particles in the studied composite can result in inadequate dynamic recrystallization, and T6 heat treatment can control the microstructure of the hot deformed TiB2/6061 Al composite. [ABSTRACT FROM AUTHOR]

Process parameters and powder spreading quality are important factors for aluminum matrix composites (AMCs) prepared using laser powder bed fusion (LPBF). In this study, a Box–Behnken Design (BBD) was used to optimize the process parameters, and near-spherical β-SiC was selected to improve the quality of powder spreading. The rationality of parameter optimization was verified by testing the density of samples prepared using different laser power levels. Al4C3 diffraction peaks were found in XRD patterns, which indicated that interface reactions occurred to form good interface bonding between the Al matrix and the SiC particles. The tensile strength and plasticity of LPBF α-SiC/AlSi10Mg were lower than that of LPBF AlSi10Mg, which was mainly due to the poor fluidity of the powder mixtures and powder spreading quality. For LPBF β-SiC/AlSi10Mg, the tensile strength increased and elongation decreased slightly compared to LPBF α-SiC/AlSi10Mg. The data in this study were compared with the data in other studies. In this study, LPBF AlSi10Mg and LPBF β-SiC/AlSi10Mg not only showed the inherent high strength of their LPBF parts, but also had relatively high plasticity. Matching between strength and plasticity was mainly dependent on the scanning strategy. Most studies use uni-directional or bi-directional scanning strategies with a certain rotation angle between layers. A chessboard scanning strategy was used in this study to form a coarse remelted connected skeleton inside the material and significantly improve plasticity. This study lays a theoretical and experimental foundation for the controllable preparation of SiC-reinforced AMCs using LPBF. [ABSTRACT FROM AUTHOR]

Enhancing the mechanical properties of conventional ceramic particles-reinforced aluminum (Al 1060) metal matrix composites (AMCs) with lower detrimental phases is difficult. In this research work, AMCs are reinforced with graphene nanosheet (GNS) and hybrid reinforcement (GNS combined with 20% SiC, synthesized by shift-speed ball milling (SSBM), and further fabricated by two-pass friction stir processing (FSP). The effect of GNS content and the addition of SiC on the microstructure and mechanical properties of AMCs are studied. The microstructure, elemental, and phase composition of the developed composite are examined using SEM, EDS, and XRD techniques, respectively. Mechanical properties such as hardness, wear, and tensile strength are analyzed. The experimental results show that the GNS and the SiC are fairly distributed in the Al matrix via SSBM, which is beneficial for the mechanical properties of the composites. The maximum tensile strength of the composites is approximately 171.3 MPa in AMCs reinforced by hybrid reinforcements. The tensile strength of the GNS/Al composites increases when the GNS content increases from 0 to 1%, but then reduces with the further increase in GNS content. The hardness increases by 2.3%, 24.9%, 28.9%, and 41.8% when the Al 1060 is reinforced with 0.5, 1, 2% GNS, and a hybrid of SiC and GNS, respectively. The SiC provides further enhancement of the hardness of AMCs reinforced by GNS. The coefficient of friction decreases by about 7%, 13%, and 17% with the reinforcement of 0.5, 1, and 2% GNS, respectively. Hybrid reinforcement has the lowest friction coefficient (0.41). The decreasing friction coefficient contributes to the self-lubrication of GNSs, the reduction in the contact area with the substrate, and the load-bearing ability of ceramic particles. According to this study, the strengthening mechanisms of the composites may be due to thermal mismatch, grain refinement, and Orowan looping. In summary, such hybrid reinforcements effectively improve the mechanical and tribological properties of the composites. [ABSTRACT FROM AUTHOR]

The mechanical properties of aluminum matrix composites at negative temperatures are assessed experimentally by means of the classification of acoustic emission pulses; attention focuses, in particular, on the ductile–brittle transition temperature. This transition does not occur even at –100°C, and so it is possible to use aluminum matrix composites for suspension components operating in the Arctic and Antarctic. [ABSTRACT FROM AUTHOR]