Strength-ductility Synergy Research Articles

Remarkable mechanical properties at room and cryogenic temperatures in a metastable high-entropy system through BCC and HCP martensitic transformations

Metastable high-entropy alloys (HEAs) with strong transformation-induced plasticity (TRIP) effects are quite desirable from the standpoint of mechanical performance. This can be achieved through ε (HCP) and α΄ (BCC) martensitic transformations during deformation, for which their importance and effectiveness should be systematically evaluated. Accordingly, in the present work, by adjusting the chemical composition of the FeCoCrNiMnV system, the formation of ε and α′-martensite was tailored. Vanadium alloying resulted in a single FCC phase, and increasing Fe at the expense of Co promoted the formation of α′-martensite over ε-martensite. The V-free Fe45Co30Cr15Ni5Mn5 HEA exhibited high strength but low ductility. However, the V-containing Fe40Co30Cr15Ni5Mn5V5, Fe45Co25Cr15Ni5Mn5V5, and Fe50Co20Cr15Ni5Mn5V5 HEAs showed much better tensile properties at room and cryogenic temperatures. The last HEA with the highest Fe content showed a remarkable room-temperature strength-ductility synergy with an ultimate tensile strength (UTS) of 826 MPa, a total elongation of 88 %, and tensile toughness of 604 MJ m−3, ascribed to the remarkable TRIP effect by the α′-martensite formation. At cryogenic temperatures, this effect resulted in a superior strength-ductility balance with a UTS of 1511 MPa, a total elongation of 68.9 %, and a tensile toughness of 814 MJ m−3. The results showed that α′-martensite formation is more important for overcoming the strength-ductility trade-off compared to ε-martensite formation in HEAs.

Superior strength-ductility synergy in additively manufactured CoCrFeNi high-entropy alloys with multi-scale hierarchical microstructure

Additive manufacturing offers a feasible route for fabricating net-shape metallic materials with advanced physicochemical and mechanical properties, which is unattainable through conventional routes. This study focuses on the processing parameters, microstructural, and mechanical properties of the CoCrFeNi high-entropy alloys (HEAs) fabricated via laser powder bed fusion (LPBF). A near-dense LPBF CoCrFeNi HEA was manufactured by fine-tuning the parameters. Compared with conventionally processed CoCrFeNi HEAs, the as-built samples exhibit excellent strength-ductility synergy with 200 % higher yield strength and unsacrificed ductility. Microstructural analyses of the LPBF samples demonstrate a hierarchical structure including melt pools, columnar grains, dislocation cells, and elemental segregations. This excellent strength is attributed to the high-density dislocation cellular structure and Cr2O3 nanoparticles that impede the dislocation motion. The excellent ductility correlates to the steady work-hardening regulated by the interactions between cellular structure, dislocations, deformation twins, and nanoprecipitation. This work provides promising outlook towards fabricating high-performance alloys with tailored hierarchical microstructure.

Effects of rolling at different temperatures and subsequent recovery annealing on the mechanical properties of a metastable carbon containing FeMnCoCr high-entropy alloy

Metallic materials or alloys consisting of single face-cubic centered (FCC) phases typically face difficulties in obtaining high strength without sacrificing ductility. The introduction of different crystalline defects via pre-straining and the activation of multiple deformation mechanisms have been shown to be effective in achieving superior strength–ductility synergy. In this work, we investigated the role of varying rolling conditions and subsequent annealing on the mechanical response in an established twinning- and transformation-induced plasticity dual phase high-entropy alloy (TWIP-TRIP-DP HEA). We found that all of the annealed samples exhibited similar nano-twinned structures. Furthermore, phase transformation from FCC γ to hexagonal close-packed (HCP) ε prevailed along the nano-twins under mechanical loading. With increasing rolling temperature, the phase stability of the matrix revealed a downward trend, resulting in a significant increase in TWIP/TRIP effects along with a prominent change in the deformation microstructure. Our study presented a simple and feasible strategy for manipulating mechanical performance by modulating the microstructural characteristics and associated deformation modes.

Current-manipulated martensite transformation to enhance strength-ductility synergy in a medium Mn steel

In order to quantify the thermal and athermal effects during pulse current assisted deformation, the deformation behavior of medium manganese steel was studied using forced air cooling. At room temperature, the ultimate tensile strength of medium manganese steel is 1350 MPa and the total elongation is 47.3 %. However, in the pulsed current assisted deformation under forced air cooling, its strength and ductility are synergistically improved, with the ultimate tensile strength increased to 1380 MPa and the total elongation increased to 57 %. Athermal effects can delay deformation-induced martensite transformation by reducing austenite dislocation density and reducing stress concentration at austenite-ferrite phase boundaries, resulting in better strength and ductility in the pulsed tensile sample with forced air cooling. While the thermal effect increases the strain energy required for deformation-induced martensite transformation, resulting in a decrease in martensitic content and a decrease in accumulated dislocation density. Therefore, compared with the sample with forced air cooling, the ultimate tensile strength of the pulse tensile sample without forced air cooling is reduced.

A single-phase Nb25Ti35V5Zr35 refractory high-entropy alloy with excellent strength-ductility synergy

Refractory high entropy alloys (RHEAs) are promising candidates for high-temperature structural materials due to their excellent high-temperature performance. However, the room-temperature brittleness of most alloys results in poor plastic formability, thereby limiting their engineering applications. In this study, Nb25Ti35V5Zr35 alloy with cold-rollability was developed, and its phase stability, tensile mechanical properties, elastic properties, strengthening mechanism, and deformation mechanism were investigated by combining experiments, CALPHAD, DFT and molecular statics (MS) methods. The results demonstrate that Nb25Ti35V5Zr35 alloy possesses good phase stability, with both the as-cast and annealed states maintaining a single-phase BCC structure without undergoing phase transformation. The tensile yield strength of the alloy reaches its peak at 1152 MPa in the cold-rolled condition, while its annealed state exhibits an optimal balance of strength and plasticity, with a yield strength of 836 MPa and an elongation of 22.45 %, respectively. Solid solution strengthening is the primary source of its high strength, with V and Zr playing key roles in this strengthening mechanism. Dislocation slip plays a dominant role in plastic deformation. Additionally, compared to traditional BCC alloys, the significance of edge dislocations in the deformation process is notably enhanced, with the {112} plane serving as the preferred slip plane for dislocations. DFT results indicate that the alloy exhibits significant anisotropy in both Young's modulus and shear modulus. This work contributes to understanding the material properties of the Nb25Ti35V5Zr35 alloy and provides a reference for the design of new ductile RHEAs.

Disrupting variant selection memory effect in laser powder bed fusion to improve strength-ductility synergy of Ti-6Al-4V alloys

Texture formation is frequently observed in parts produced by Laser Powder Bed Fusion (L-PBF), which can induce anisotropy and may potentially degrade plasticity. In this study, we introduce a laser remelting strategy to mitigate these adverse effects. By employing experimental observations and numerical simulations, we established the relationship between melt pool thermal history, variant selection, and mechanical properties. Our results indicate that the strengthening of texture can be prevented by disrupting the variant selection memory effect when there is a difference in scanning speeds between the printing and remelting lasers. The achieved random variant orientation is attributed to the altered cooling rates and temperature gradient directions during solidification across different layers. The optimized Ti-6Al-4V alloy demonstrates high strength (1211.5 ± 13 MPa) and significant elongation (12.3% ± 0.8%), exhibiting a superior strength-ductility synergy compared to samples produced by direct printing or laser remelting with consistent parameters, as well as most reported L-PBF processed Ti-6Al-4V alloys. Our findings provide new insights into phase transformation kinetics in L-PBF of Ti-6Al-4V alloys and facilitate the optimization of this process for manufacturing high-performance components.

Excellent strength-ductility synergy assisted by dislocation dipole-induced plasticity in Co-free precipitate-strengthened medium-entropy alloy

Precipitation strengthening is one of the most effective approaches for developing advanced structural materials with outstanding strength-ductility combinations. However, most compositional designs of precipitate-strengthened HEAs/MEAs compromise the cost-property tradeoff owing to the addition of expensive Co element. In this study, a Co-free FeCrNi-based precipitate-strengthened medium entropy alloy (denoted as Al0.2Cr0.9FeNi2.2Ti0.2) with a near-equiatomic FeCrNi matrix and a high content (∼ 35 %) L12 nanoprecipitates was designed using a mixing strategy. The microstructural features, mechanical performance, deformation substructure evolution, and strengthening mechanisms were systematically investigated using EBSD, TEM, and APT. Tensile tests indicated that the current alloy aged within a moderate temperature range achieved an exceptional strength-ductility combination compared to existing Co-containing and Co-free HEAs/MEAs. Particularly, the alloy aged at 700 ℃ (denoted as 700A) demonstrated a high ultimate tensile strength of 1606 MPa and a large ductility of 25 %, benefiting from both precipitation hardening and an unusual strain-hardening sustainability. Such anomalous strain-hardening sustainability can be attributed to the dislocation dipole-induced plasticity. High-density dislocation dipoles can simultaneously provide additional strain hardening by reducing the dislocation mean free path and enhance plastic deformation compatibility by acting as stress delocalization origins, thereby contributing to excellent strength-ductility synergy. These findings will not only open a new door for the future development of high-performance Co-free precipitate-strengthened HEAs/MEAs, but also deepen the understanding of the work-hardening mechanisms in these alloys.

Hierarchical modification of bimodal grain structure in Al/Ti laminated composites for extraordinary strength-ductility synergy

Al/Ti laminates with altering Al grain sizes was fabricated via hot press sintering. Fine Al powders results in low sintering density and obvious cracks at Al/Ti interface. Large Al powders greatly increased the grain size, grain aspect ratio, LAGBs fraction, and recrystallization fraction of the Al layers. The texture heterogeneity is also significant, with rolling texture in Ti layer and random texture in Al layer. Ti5Si3 phase precipitated at Al/Ti interface, and it gradually partitioned Ti atoms from TiAl3 and hindered the formation of TiAl3. Moreover, numerous stacking faults, dislocation loops, dislocation pinning, and dislocation tangles were observed at Al/Ti interface, resulting in an increased back stress. Large Al grains contributes the highest bending strength of 734.8 MPa, tensile strength of 753.2 MPa, and fracture strain of 62 %. The effect of grain size on work hardening was attributed to the fraction of LAGBs, dislocation storage capacity and additional HDI strengthening.

Strength-ductility synergy in a non-equiatomic Co–Cr–Ni medium entropy alloy wall structure deposited using twin-wire arc additive manufacturing

An innovative twin-wire arc additive manufacturing (T-WAAM) has been deployed to fabricate a Co-rich non-equiatomic Co–Cr–Ni medium entropy alloy. The TWAAM-built single-wall structures of Co50Cr10Ni40 alloy were fabricated under argon gas shielding using dual gas metal arc welding sources. The microstructure studies revealed a single-phase FCC crystal structure and defect-free deposition. The slender columnar substructure and cellular substructure are formed along the build direction (BD) and scan direction (SD) respectively, which are commonly observed in the wall structures of other conventional FCC alloys. The tensile coupon SD and BD displayed a superior high strength and ductility combination. The T-WAAM-fabricated Co50Cr10Ni40 alloy showed both strength and elongation 1.4 times greater than that of the laser additive manufactured equiatomic CoCrNi wall structure. Thus, the study opens up a new avenue to tailor the mechanical properties of CoCrNi MEA by composition variation, with an added advantage of higher deposition rates of TWAAM.

Simultaneously improving the strength and ductility of an oxide dispersion-strengthened high-entropy alloy by employing innovative precursors for oxide formation

The engineering of a composite microstructure, achieved by coupling heterogeneous grain distribution with oxide dispersion, has been demonstrated as an effective strategy for enhancing the strength-ductility synergy of alloys at both room and elevated temperatures. The effectiveness of this approach is strongly correlated with the micro-features of dispersed oxides. In this study, we selected the Ni38Co20Cr20Fe18Ti4 high-entropy alloy (HEA) as the base material, which could achieve the desired composite structure through preparation using mechanical alloying and spark plasma sintering methods. Our primary objective was to investigate the effects of incorporating Y2O3 or utilizing hydrides (TiH2 and YH3) as alternative precursors on the modification of oxide precipitates, evolution of a bimodal grain microstructure, and alteration in mechanical properties for the oxide dispersion strengthened (ODS) HEA. The results show that the incorporation of Y2O3 promotes the formation of ultrafine and semi-coherent Y2Ti2O7 ternary oxide particles, in addition to the pre-existing coarse binary TiO in the HEA matrix. Moreover, this leads to a significant increase in the fraction and a decrease in the average size of ultrafine grains (UFGs) within the bimodal microstructure. Notably, utilizing Ti- and Y-hydrides instead of Y2O3 and Ti as oxide-forming precursors within an equivalent composition remarkably amplifies the precipitation proportion of Y2Ti2O7 among dispersoids while further refining UFGs. The ODS-HEA synthesized using hydrides exhibits a simultaneous enhancement of 12 % in yield strength and 13 % in elongation to fracture, compared to that prepared from Ti and Y2O3. This intriguing phenomenon primarily arises from the heightened strengthening and toughening contributions, facilitated by the increased precipitation of advantageous Y2Ti2O7 nanoparticles.

Strong and ductile Resinvar alloys with temperature- and time-independent resistivity

Materials with well-defined electrical resistivity that does not change with temperature or time are important in robotics, communication and automation. However, the challenge of designing such materials has remained elusive due to the temperature-dependent electron-phonon scattering. Moreover, resistive electrical conductors used in flexible and mobile systems under high mechanical loads must possess both high strength and ductility. Achieving such multi-properties presents a fundamental challenge. Here, we solve this problem by combining multicomponent alloy design with atomic-scale chemistry tuning. We term the resultant material ‘Resinvar’ alloy, due to its invariable resistivity (148 μΩ·cm) over wide temperature ranges from room temperature to 723 K. The alloy also has high tensile strength (948 MPa) at large tensile elongation (53%). The distorted lattice, chemical short-range order and ordered coherent nanoprecipitates in the material enable the invariant resistivity via promoting temperature-independent inelastic electron scattering, and contribute to the excellent strength-ductility synergy by manipulating dislocation slip.

Achieving strength-ductility synergy in LPBF Ti-6Al-8 V alloy through in situ alloying

This study utilized in situ alloying during laser powder bed fusion (LPBF) to create a novel Ti-6Al-8V (wt. %, Ti68) alloy. Pure vanadium nanoparticles were incorporated into Ti-6Al-4V feedstock at a concentration of 4 wt.%. The resulting Ti68 alloy displayed exceptional mechanical properties, including a ultimate tensile strength of 1163 ± 34 MPa and a fracture elongation of 13.1 ± 2.0 %. These improvements can be attributed to the unique microstructure of this alloy, characterized by a heterogeneous α’+β phase resulting from the uneven distribution of vanadium. This microstructure enables sustained plastic deformation through dislocation slip and twinning in α’ phase, as well as dislocation slip and stress-induced martensitic transformation in β phase.

Enhancing strength-ductility synergy in low-Mn lightweight steel by large-deformed warm rolling and flash annealing

The presence of δ-ferrite makes it challenging to achieve higher strength-ductility in low-Mn lightweight steels. In this study, a large deformation warm rolling process was used to construct a precursor enriched with Mn, nano-precipitations, ultra-fine grains, and high-density dislocations. The subsequent flash annealing process not only promotes the formation of multi-heterogeneous structures but also refines and reduces δ-ferrite while increasing the ultrafine-grained hard phase martensite. Additionally, this process enhances the retention of retained austenite, whose ultrafine grains contribute to improved mechanical stability. The synergistic effect of multiple strengthening mechanisms enables low-Mn lightweight steel to achieve outstanding comprehensive mechanical properties, with a tensile strength of 1423 MPa and a total elongation of 23.0 %.

Enhanced thermal stability in additive friction stir deposited ODS IN9052 Al alloy

Mechanically alloyed (MA) oxide dispersion strengthened (ODS) IN9052 Al alloy exhibits excellent strength both at ambient and high temperatures (up to 300 °C). The limited ductility at ambient temperatures, stemming primarily from the inherent microstructure, impede its practical appeal in structural applications. The present study signifies a maiden effort to additively manufacture MA-ODS IN9052 alloy using solid-state additive friction stir deposition (AFSD) process which has added advantages of uniform particle dispersion, severe particle breakdown, and a recrystallized microstructure. This study indicates a remarkable transition from the initial strain softening behavior in the as received alloy to significant work hardening in the AFSD condition, while maintaining satisfactory yield strength of ∼380 MPa at ambient temperature highlighting a favorable strength-ductility synergy. Importantly, exceptional thermal stability has been achieved in the AFSD alloy by systematically optimizing the process parameters to engineer microstructural heterogeneity. The AFSD alloy demonstrated an impressive high temperature strength, with ∼22 % and ∼49 % increase in yield strength as compared to forged alloy at 240 °C and 340 °C, respectively. Enhancing high temperature strength in aluminum alloys has been a long standing goal and the current results outperform other commercially available high temperature Al alloys. Excellent thermal stability in the AFSD processed alloy is attributed to the nano-scale carbon-rich cluster formation around oxides and carbides in the matrix. These particles restrict grain boundary sliding and are more effective in dislocation-particle interaction. The findings are supported by detailed TEM and atom probe tomography analysis.

Fabricating a pure titanium foil with excellent strength-ductility combination via bimodal grain structure coupling with deformation twins

Preparation of pure titanium foil by cold rolling deformation often confronts the strength-ductility trade-off dilemma, how to obtain an excellent strength-ductility combination remains a great challenge. In the present work, we have prepared a pure titanium foil with a bimodal grain (BG) structure consisting of coarse grain (CG) and ultrafine grain (UFG), coupling with high-density deformation twins (DT) via a cryogenic-temperature rolling (CTR) and partial recrystallization annealing (PRA) process. Notably, a high strength-ductility synergy with YS of ∼483 MPa, UTS of ∼517 MPa and elongation of ∼21 % is achieved. The high strength is mainly caused by pronounced fine grain strengthening from the UFG region and twin boundary strengthening from strong interactions between DT and dislocations activated in the CG region. The GND caused by the hetero-deformation between CG and UFG, along with the activation of pyramidal <c+a> dislocation via DT in the CG region endows the pure titanium foil with excellent ductility.

A fully recrystallized heterogeneous grain structure with dispersed second phases for enhancing strength-ductility synergy in an Al-Cu-Mn alloy

Introducing heterogeneous grain structures has been demonstrated as an effective strategy to overcome the strength-ductility trade-off in metallic materials. Here, we designed a fully recrystallized heterogeneous microstructure via controlling local recrystallization around the grain boundaries coupled with the second phase. The representative feature of this microstructure is the topology of the nearest grain neighbors, where a fully recovered large grain is surrounded by multiple recrystallized small grains. Meanwhile, the second phase distribution around the grain boundary could be remarkably optimized during the processing. Within a commercial Al-Cu-Mn alloy, a remarkable ultimate tensile strength of 365 MPa with uniform elongation of 30 % was achieved through this heterogeneous structure, corresponding to an 18 % increase in ultimate tensile strength and a 29 % improvement in ductility compared with the uniform-grained counterpart. Characterized by quasi-in-situ EBSD, it was found that the multiple small grain neighbors coordinated local strain incompatibility near the hetero-interface by dislocation slips and local reorientations, which can better sustain the strain hardening. In situ tensile tests unveiled the micro-crack blunting by ductile large grains, endowing superior crack-arrest capability. Moreover, tailored dispersed Al2Cu particles inhibited inter-cluster void coalescence and interface-debonding by eliminating continuous crack growth paths, promoting stable damage evolution. These results give a new insight into the controllable design of heterogeneous-grained alloys with second phases for achieving superior combinations of mechanical properties.

Synchronous improvement in strength and ductility of Cu-bearing stainless steels through formation of bimodal grain structure induced by short-time electric pulses

Excellent strength and favorable formability are two important mechanical properties of stainless steel, but there is usually a trade-off between both properties. However, it has been suggested in recent studies that preparing microstructures with a non-homogeneous structure can effectively achieve strength-ductility synergy. Given these facts, a microstructure with bimodal grain structures was prepared in this study by short-time electric pulse treatment (EPT). Besides, the evolution of microstructures and mechanical properties of Cu-bearing stainless steel during EPT was analyzed. The results demonstrated that the non-uniform heating in the EPT process can rapidly promote localized grain growth, thus forming a bimodal grain structure compared with conventional heat treatment. The microstructure of the fine grains formed random textures, while the coarsened grains showed stronger textures. After EPT, the amount of S {123} < 634 < 634 >-type textures increased significantly, with the proportion reaching up to 30.1 %. There was also a certain amount of brass {110} < 112 >- and copper {112} < 111 >-type textures. Compared with the solution-treated samples, the best overall mechanical properties were detected under the optimal electric pulse parameters, which ultimately realized a synergistic increase of 11.8 % and 10.2 % in the ultimate tensile strength and ductility. The excellent strength-ductility synergy was closely related to heterogeneous deformation-induced (HDI) strengthening and textures induced by the bimodal grain structure. This finding may provide novel insights for enhancing the formability of biomedical metallic materials.

Effects of Sn and Mn additions on microstructural characteristics and tensile properties of Mg-1Gd alloy

Effects of Sn, Mn, and their combined additions on microstructural characteristic and tensile properties of extruded Mg-1Gd (G1) alloy are explored. Compared to the sole Sn or Mn addition, an excellent grain refining is happened with the Sn and Mn combined addition. The average grain size of G1, Mg-1Gd-0.8Sn (GS10), Mg-1Gd-0.7Mn (GM10) and Mg-1Gd-0.8Sn-0.7Mn (GSM100) alloys is ∼21.3, 10.1, ∼12.8 and ∼6.8 μm, respectively. The sole Mn addition enhances the strength and ductility of G1 alloy. The forming the fine α-Mn particles and grain refining are attributed to the improved properties of GM10 alloy. The sole Sn addition increases the yield strength of G1 alloy along extrusion direction (ED), but it decreases along transverse direction (TD), The inhomogeneous distribution of coarse GdMgSn particles and formation of TD-split texture should play an important role. The combined effects of Sn and Mn additions guarantee high strength-ductility synergy of GSM100 alloy. The GSM100 alloy exhibits the ultimate strength, yield strength and ductility of ∼276, ∼158 MPa and 24.7 % along ED, and ∼253, ∼157 MPa and 17.5 % along TD, respectively. The jointly effect of the fine grains, a lot of fine GdMgSn and α-Mn particles, the texture weakening and Sn solute atom contributes to the enhancement of properties of GSM100 alloy.

Fine grains, dispersed phases and strong crystal defect interactions inducing excellent strength-ductility synergy in powder sintered Cu–18Sn-0.3Ti alloy via hot extrusion and solution treatment

In order to prepare the Cu–18Sn-0.3Ti alloy with excellent mechanical properties to realize the favorable collaborative deformation of Cu–18Sn-0.3Ti alloy and Nb in the preparation process of Nb3Sn superconducting wires by bronze method, the hot extrusion process of the Cu–18Sn-0.3Ti alloy prepared by Direct Current assisted Hot Pressed sintering based on micron atomized spherical alloy powders was systematically investigated by the combination of experiments and finite element simulation in this work. The ultimate tensile strength, yield strength and elongation can reach 683.5 MPa, 414.3 MPa and 33.3 %, respectively, through the optimization of hot extrusion parameters and subsequent solution treatment. The results show that hot extrusion with high strain rate induced the formation of fine α grains and dispersed δ phases. Especially, strong dislocations-annealing twins (ATs) interaction occurred, which was manifested as the pile-up of dislocations at twin boundaries of ATs, slippage of dislocations in multiple directions inside ATs and storage of dislocations inside ATs. Meanwhile, the high strain rate induced the formation of deformation twins inside partial grains. The grain refinement of α matrix, formation of dispersed δ phases and strong interactions of crystal defects were the main reasons for the strength-ductility enhancement of hot extruded samples, and laid an excellent microstructure foundation for further improving the mechanical properties of alloy by subsequent solution treatment. The results not only describe a feasible method for simultaneously enhancing the strength and ductility of Cu–18Sn-0.3Ti alloy, but also provide a theoretical guidance for the strength-ductility enhancement of multicomponent alloys.

Trimodal Grain Structured Aluminum Matrix Composites Regulated by Transitional Hetero-Domains

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.