Superior Ductility Research Articles

Experimental and numerical study of corrugated steel-plain concrete composite structures under contact explosions

This paper investigates the dynamic response and blast resistance of corrugated steel-plain concrete (CSPC) composite structures subjected to contact blast. A series of explosive tests were conducted to investigate the acceleration, deformation, and damage patterns of CSPC plates under varying blast loads and arrangements of shear connectors, and these findings were compared with reinforced concrete (RC) plates. The results suggested that CSPC plates exhibited superior ductility and blast resistance, and effectively mitigated concrete collapse. The CSPC slab primarily underwent elastic deformation when the TNT charge was small, with the rebound deformation of the concrete and steel plates acting as a significant mode of energy dissipation. As for larger TNT charges, the maximum deformation of the plate progressively increased, especially when exceeding 0.3 kg, the deformation rebound ratio decreased significantly, and the plastic deformation increased. For further increased explosive loads, the concrete and steel plates exhibited a pronounced strain rate effect with a slowed growth rate of deformation. By examining different configurations of shear connectors, it was discovered that the adhesive strength between concrete and steel plates was closely related to the energy dissipation mode, and the elastic recovery capability and deformation resistance of the CSPC structure significantly deteriorated when the shear connectors were shorter, sparser or thinner. A numerical model based on LS-DYNA was designed to further analyze the blast resistance characteristics of CSPC plates. An engineering collapse coefficient Kz was established to predict the failure level of the CSPC plates. This paper provides useful insights for the optimal design and damage assessment of CSPC composite structures.

Aging temperature effect on the phase composition, microstructure, and selected mechanical properties of non-equiatomic TiZrNbTaMo/Mn HEAs targeted for biomedical implants

High entropy alloys (HEAs) have been developed for many applications and recognized for their superior strength, ductility, and corrosion resistance, attracting the attention for biomedical applications. This study aims to evaluate the effect of aging treatment at distinct temperatures on the phase composition, microstructure, and selected mechanical properties of non-equiatomic TiZrNbTaMo and TiZrMoNbTaMn HEAs for potential use as biomedical implants. The TiZrNbTaMn sample exhibited a single BCC phase, while the TiZrNbTaMo a major BCC and minor HCP phases. The microstructure of the TiZrNbTaMo sample was composed of BCC grains with some acicular precipitations of the HCP phase in the grain boundaries, having the aging temperature acted in the grain growth and secondary phase precipitation. Contrarily, the TiZrNbTaMn sample exhibited larger BCC grains permeated with a minor amount of acicular structures, which were entirely decomposed with the aging treatments. The semi-quantitative chemical analysis indicated that the phase composition was a result of elemental chemical segregation, having the refractory metals (Mo, Ta, and Nb) preferentially located in the inner region of the grains, while the other ones (Ti, Zr, and Mn) in the grain boundary. The aging treatment acted in the phase precipitation/dissolution oppositely on the samples through the atomic diffusion mechanism induced by the temperature. The elastic modulus and Vickers microhardness were sensitive to the chemical and phase composition of the samples, having the TiZrNbTaMo aged at 773 K achieved better performance than the commercial Ti-6Al-4 V alloy for use as biomedical implants.

Negative enthalpy alloys and local chemical ordering: a concept and route leading to synergy of strength and ductility.

Solid solutions are ubiquitous in metals and alloys. Local chemical ordering (LCO) is a fundamental sub-nano/nanoscale process that occurs in many solid solutions and can be used as a microstructure to optimize strength and ductility. However, the formation of LCO has not been fully elucidated, let alone how to provide efficient routes for designing LCO to achieve synergistic effects on both superb strength and ductility. Herein, we propose the formation and control of LCO in negative enthalpy alloys. With engineering negative enthalpy in solid solutions, genetic LCO components are formed in negative enthalpy refractory high-entropy alloys (RHEAs). In contrast to conventional 'trial-and-error' approaches, the control of LCO by using engineering negative enthalpy in RHEAs is instructive and results in superior strength (1160MPa) and uniform ductility (24.5%) under tension at ambient temperature, which are among the best reported so far. LCO can promote dislocation cross-slip, enhancing the interaction between dislocations and their accumulation at large tensile strains; sustainable strain hardening can thereby be attained to ensure high ductility of the alloy. This work paves the way for new research fields on negative enthalpy solid solutions and alloys for the synergy of strength and ductility as well as new functions.

Atomic-scale observation of nucleation- and growth-controlled deformation twinning in body-centered cubic nanocrystals

Twinning is an essential mode of plastic deformation for achieving superior strength and ductility in metallic nanostructures. It has been generally believed that twinning-induced plasticity in body-centered cubic (BCC) metals is controlled by twin nucleation, but facilitated by rapid twin growth once the nucleation energy barrier is overcome. By performing in situ atomic-scale transmission electron microscopy straining experiments and atomistic simulations, we find that deformation twinning in BCC Ta nanocrystals larger than 15 nm in diameter proceeds by reluctant twin growth, resulting from slow advancement of twinning partials along the boundaries of finite-sized twin structures. In contrast, reluctant twin growth can be obviated by reducing the nanocrystal diameter to below 15 nm. As a result, the nucleated twin structure penetrates quickly through the cross section of nanocrystals, enabling fast twin growth via facile migration of twin boundaries leading to large uniform plastic deformation. The present work reveals a size-dependent transition in the nucleation- and growth-controlled twinning mechanism in BCC metals, and provides insights for exploiting twinning-induced plasticity and breaking strength-ductility limits in nanostructured BCC metals.

Numerical and Experimental Studies on Crack Resistance of Ultra-High-Performance Concrete Decorative Panels for Bridges

This study develops a new type of decorative bridge panel by ultra-high-performance concrete (UHPC) based on the project of the Guangyangwan Bridge. First, the numerical analysis was carried out using MIDAS and ABAQUS to find the critical position of the bridge and decorative panels. The numerical results showed that the last concrete cantilever segment had the greatest vertical deflection, and the corresponding panel had the greatest stress response. Based on the numerical results, this study conducted a series of full-scale, self-balanced bending tests to examine the crack resistance of six UHPC panels and six glass fiber-reinforced concrete (GRC) panels with varying curved section thicknesses (from 25 to 40 mm). The experimental results indicate that, due to the high strength of the UHPC matrix and the wall effect of steel fiber distribution, the crack resistance of UHPC panels is significantly superior to that of GRC panels. UHPC panels possessed superior stiffness and ductility, while GRC panels showed brittle fracture when the curved section thickness reached 34 mm. The uniaxial tensile cracking strength of UHPC with a steel fiber volume fraction of 1.6% was 14.7% greater than that of GRC with a glass fiber volume fraction of 5%. At the same curved section thicknesses, UHPC decorative panels exhibit cracking loads and ultimate loads that are 64.3% to 123.0% and 29.2% to 115.0% greater than GRC panels, respectively. Hence, UHPC is more suitable to produce ultra-thin decorative panels for bridges that are subjected to severe environmental action and external forces.

Selective laser melting processing of heterostructured Ti6Al4V/FeCoNiCrMo alloy with superior strength and ductility

In the selective laser melting (SLM) process, the transient nature of the molten pool and rapid cooling rate facilitates partial homogenization of components, resulting in attaining a finer scale concentration modulation and spatial heterostructure. However, the SLM-processed Ti6Al4V alloys have long suffered from the problem of both large detrimental columnar grains and poor work-hardening capacity. In this study, a high entropy alloy of FeCoNiCrMo particles was incorporated into the Ti6Al4V alloy and fabricated by the SLM technique. The resulting alloys exhibited a fine-scale modulated β + α' spatial heterostructure, delivering a notable tensile strength of 1366.4 MPa and a uniform elongation of approximately 8.7% with an excellent work-hardening capacity exceeding 300 MPa. This outstanding performance can be attributed to the progressive transformation-induced plasticity (TRIP) effect and hetero-deformation induced (HDI) strengthening within the ultra-refined α' martensite and metastable β phase regions. This work provided a compelling model of additive manufacture of heterogeneous structures while offering new insights and directions for the development of metallic materials with high strength-ductility characteristics.

Recent Developments of Bioactive Glass Electrophoretically Coated Cobalt-Chromium Metallic Implants

Coating surfaces with bioactive glass can be defined as depositing fine bioactive glasses on biomaterial substrates. Cobalt-chromium is a viable alternative to stainless steel for long-term applications with superior ductility. The mechanical properties of cobalt-chromium alloys are high strength with elastic modulus of 220–2300 GPa, more significant than the 30 GPa of bones. Combining metals and bioactive glass results in high biocompatibility and improved bioactivity of implant surfaces. In addition, it triggers new bone tissue to regenerate through osteogenesis and mineralisation. However, implantation failure still occurs and requires surgery revision due to a lack of adequate bone bonding and delamination at the coating surface of the implant. The current review summarises the adhesion between bioactive glass coatings and cobalt-chromium substrates applied through electrophoretic deposition (EPD).

The discrepancy in basal slip hardening rates of cast and extruded Mg-Y-Zr alloys

The differences in the deformation mechanisms during uniaxial tension of cast and extruded Mg–2Y-0.5Zr (wt%) alloys have been investigated by using EBSD-based slip trace analysis and VPSC simulation methods, and a novel method for counting the activity of slip/twinning using grain area has been proposed. Slip trace analysis reveals that enhanced ductility and reduced tensile-compressive asymmetry observed in the Mg–2Y-0.5Zr (wt%) alloy can be attributed to the addition of the Y element, which modified the texture, and promoted pyramidal <c + a> slip and suppressed prismatic <a> slip. The extruded alloy exhibits a distinctive pseudo-fiber bimodal microstructure, which contributes to its superior ductility. The VPSC results indicate that the CRSSnon-basal/CRSSbasal ratio of the extruded alloys decreases, whereas the CRSStwinning/CRSSbasal ratio increases, which is attributed to the different effects of the grain refinement on the different deformation modes. In addition, both the VPSC results and the slip trace analysis results indicate that the extruded alloy exhibits reduced non-basal slip activity compared to the cast alloy at similar strain levels. The work-hardening rate curves and VPSC parameters give a reasonable explanation that the key to the increase in the ductility of Mg–Y–Zr alloys after extrusion is the decrease in the basal hardening rate rather than the non-basal slip activity. The refinement of grain size leads to a significant decrease in basal slip hardening rate, primarily due to the decrease in the additional hardening effect caused by tensile twinning and the generation of an additional GBS mechanism in the pseudo fiber microstructure.

Elliptical concrete-filled FRP tubes with an embedded H-shaped steel under axial compression and cyclic lateral loading: Experimental study and modelling

Concrete-filled FRP tubes (CFFTs) have found increasing applications due to their superior ductility and remarkable corrosion resistance. In published literature, circular CFFTs and rectangular CFFTs have been investigated extensively, while there are relatively few studies on elliptical CFFTs. There is no research about elliptical CFFTs with an embedded H-shaped steel (i.e., HS-ECFFTs) under axial compression and cyclic lateral loading. Against this background, this paper investigated the seismic behaviour of HS-ECFFTs experimentally and numerically. Test results indicated that: (1) all HS-ECFFTs performed well with remarkable energy dissipation ability; (2) due to the effective FRP confinement, the local buckling of the H-shaped steel was prohibited; (3) the elliptical aspect ratio had limited influences on the ductility, the stiffness degradation and the energy dissipation; (4) the FRP thickness, after a certain threshold, showed beneficial but limited influences on the peak load, the stiffness degradation and the energy dissipation; (5) the HS-ECFFT specimen performed much better in terms of the peak load, the ductility, the stiffness degradation and the energy dissipation when it was bending around the strong axis. The proposed numerical model established on the OpenSees platform could generate reasonably accurate numerical results for all HS-ECFFTs.

Microstructure and mechanical property of A356 cast remanufactured by ultrasonic frequency pulsed TIG process

Remanufacturing quality is critical to the service performance of aluminum alloy castings. Here, casted A356 Al7Si0.3 Mg alloy was remanufactured by using ultrasonic frequency pulsed (UFP) TIG deposition process. The heterogeneous microstructure evolution, hardness distribution, and tensile behavior of the repaired part were investigated and discussed. The UTS, YS and elongation of the UFP-TIG remanufactured A356 are 183 MPa, 121 MPa and 3.3 %, respectively. The repaired part shows a strength coefficient of 0.93 and superior ductility over the cast.

Synthesis of core–shell ZnO nanoparticles and their effect on mechanical and antibacterial properties for PLLA/ZnO nanocomposites

AbstractTo overcome the inherent brittleness of renewable poly(l‐lactide) acid (PLLA) and enable it for use in a wide application, we successfully synthesized the toughening agent of ZnO nanoparticles grafted by poly(caprolactone‐co‐d‐lactide) (ZnO‐g‐PCLDLA) via sequential open‐loop polymerization. First, ZnO was silanized to produce hydroxyl groups on the surface of the nanoparticles. Initiated by hydroxyl groups on the ZnO core, the rubbery PCLDLA composed of caprolactone‐d‐lactide co‐polymeric segments and d‐lactide homo‐polymeric segments was successively polymerized, forming ZnO core–shell nanoparticles. PLLA/ZnO‐g‐PCLDLA nanocomposites were prepared by solution blending. The nanocomposites with 10 wt% ZnO‐g‐PCLDLA exhibited superior ductility, whose elongation at break was about 54 times higher than that of neat PLLA. This considerable increment of toughness was attributed to the rubbery shell of PCLDLA and the enhanced interfacial interaction from the interfacial stereocomplex crystallites, formed by co‐crystallization of the PLLA matrix and d‐lactide homo‐polymeric segments of the PCLDLA shell on ZnO. The PLLA/ZnO‐g‐ PCLDLA nanocomposite films possessed outstanding antimicrobial properties against Staphylococcus aureus and Escherichia coli. Positive ZnO produces an electrostatic force to interact with the negatively charged membrane of bacteria, thereby damaging the cell membrane and achieving significant antibacterial effects.Highlights ZnO‐g‐PCLDLA core–shell nanoparticles were constructed by sequential ROP. The ZnO core provided high rigidity and antimicrobial properties. The rubbery PCLDLA shell provided high elasticity and ductility. Interfacial interaction was greatly enhanced by the SC crystallites. The PLLA nanocomposite films exhibited outstanding antimicrobial activity.

Room‐Temperature Cubic Ag2S1−2xSexTex with Promising Ductility and Thermoelectric Properties Enabled by Entropy Engineering

AbstractSince the discovery of superior ductility in semiconducting Ag2S at room temperature, Ag2S‐based inorganics attract ever‐increasing attention as ductile thermoelectrics (TEs) for flexible electronics, while the monoclinic to cubic structure transition near room temperature (≈455 K for Ag2S) of these materials leads to instability of their structures and properties. In this work, single‐phase cubic Ag2S1−2xSexTex (x = 0.13–0.33) samples are stabilized at room temperature via entropy engineering. In comparison with pure Ag2S, the random mixing of S, Se, and Te at the anion site results in increased configuration entropy, improved electrical conductivity, decreased lattice thermal conductivity, and thus significantly enhanced TE properties of cubic Ag2S1−2xSexTex samples. By further optimizing the carrier concentration through introducing Ag vacancies, the slightly Ag‐deficient Ag1.98S0.34Se0.33Te0.33 sample achieves a power factor of 6.1 µW cm−1 K−2 and a dimensionless figure of merit zT of 0.4 at room temperature. In the measured temperature range of 300–500 K, this cubic sample with excellent ductility shows not only a record average zT value of 0.62 in ductile inorganics but also very stable TE properties, demonstrating the great potential of entropy engineering in the design of high‐performance ductile TE inorganics.

Experimental investigations on microstructure and mechanical properties of wall structure of SS309L using wire-arc additive manufacturing

In present study, a wall structure of SS309L was constructed through Gas metal arc welding based Wire-arc additive manufacturing process. The wall structure of SS309L underwent investigation for microstructure and mechanical properties at three positions along the horizontal deposition direction. Mechanical assessments, including microhardness testing, impact testing, tensile testing, and fractography, were conducted at three positions of walls. Microstructure study has shown a fine granular structure in addition to colony of columnar dendrites in bottom section, a columnar dendrites in middle section, and a mix of dendritic structure with even coarser structures in top section. The mean microhardness values were observed to be 159 ± 4.21 HV, 162 ± 3.89 HV, and 168 ± 5.34 HV for the top, middle, and bottom sections, respectively. Results of impact testing for the wall structure indicated greater strength compared to wrought SS309L. The tensile strength of the built structure showed average values of yield strength, ultimate tensile strength, and elongation to be 409.33 ± 7.66 MPa, 556.66 ± 6.33 MPa, and 39.66 ± 2.33 %, respectively. In comparison, wrought 309 L steel typically exhibits tensile strengths in the range of 360–480 MPa for yield strength, 530–650 MPa for ultimate tensile strength, and 35–45 % elongation. Thus, the obtained tensile strength results for the wall structure fall within the range of tensile strength observed in wrought 309 L steel. Fractography of the tensile and impact specimens, as obtained through Scanning Electron Microscopy, revealed the superior ductility of the fabricated component. This study contributes valuable insights into the manufacturing of wall structure and their analysis regarding mechanical characteristics.

TRIP-TWIP effect in deformation mechanisms of Co–Cr–Ni medium entropy via molecular dynamics simulations

Recently, Co–Cr–Ni medium-entropy alloys (MEAs) have garnered significant attention in the materials field owing to exceptional properties. However, the various mechanisms of transformation induced plasticity (TRIP) and twinning induced plasticity (TWIP) effects with variation of chemical compositions, strain rates, temperature and grain size in polycrystalline Co–Cr–Ni MEAs remains challenging. By utilizing molecular dynamics simulations, the uniaxial tensile deformation of polycrystalline Co–Cr–Ni MEAs, including equiatomic CoCrNi, and non-equiatomic Co10(CrNi)90, Cr10(CoNi)90 and Ni10(CoCr)90, has been investigated. The influence of strain rates and deformation temperatures on the mechanical properties and deformation mechanisms of CoCrNi MEA has also been explored under uniaxial tensile loading. Further, dislocation multiplication, slip motion, microstructure evolution, and their interplay with tensile deformation under different conditions have also been studied. Additionally, the relationship between different grain sizes and the flow stress of polycrystalline CoCrNi MEA has also been discussed. The findings reveal that Co10(CrNi)90 MEA exhibits highest yield stress, Young's modulus, and flow stress. While CoCrNi MEA and Cr10(CoNi)90 MEA with equiatomic ratios display similar mechanical properties, Ni10(CoCr)90 MEA demonstrates superior ductility owing to the strong TWIP and TRIP effects. Besides, strain rate, deformation temperature, and grain size all have significant impacts on the deformation mechanisms of polycrystalline CoCrNi MEA.

Immobilization of Kluyveromyces marxianus K21 via coaxial electrospinning of PVA and sugarcane bagasse composite for bioethanol production

The study employed coaxial electrospinning technology to design an immobilization system for ethanol production from a sugarcane bagasse (SCB) and polyvinyl alcohol (PVA) composite. Using response surface methodology (RSM), the most suitable pretreatment conditions were 1.84 N H2SO4 at 70.85 °C for 30 min which resulted in 4.73 mg polysaccharide per 1 mL of SCB being extracted, comparing to the theoretical value of 4.51 mg. According to physical characterization analyses, both PVA/SCB and yeast-embedded PVA/SCB composites had superior strength and ductility compared to PVA-only sample. With 36.5 g/L of sugar consumption, a total of 18.01 g/L ethanol was produced after 10 h of cultivation from PVA/SCB/K21 which was higher than that from the freely suspended culture (15.31 g/L at 12 h), resulting in a 15% increase in yield. Furthermore, the PVA/SCB/K21 system was able to maintain constant ethanol production even after 21 days of storage, and could be reused in fermentation for at least 8 cycles. The findings showed that the PVA/SCB/K21 nanothreads is an ideal system for repeated bioethanol production while upcycling sugarcane bagasse biomass waste.

Illuminating the mechanical responses of amorphous boron nitride through deep learning: A molecular dynamics study

Amorphous boron nitride (a-BN) has recently emerged as a promising ultralow-dielectric-constant material for interconnect isolation in integrated circuits. However, its mechanical properties remain poorly understood. This study establishes a deep learning potential (DLP) for hexagonal boron nitride (h-BN), cubic boron nitride (c-BN), and a-BN based on density functional theory data. The DLP accurately captures energies, forces, and virial stresses compared to direct DFT calculations. Molecular dynamics simulations employing the DLP are conducted to investigate the mechanical behaviors of a-BNs with varying densities under uniaxial tension. The results reveal that higher density a-BN exhibits increased Young's modulus and yield stress but reduced ductility, while lower density a-BN displays superior ductility and higher ultimate strain. The formation of local distortion and evolution of cracks are examined using atomic local shear strain. This work elucidates structure–property relationships in a-BN through simulations, providing useful insights for integrating a-BN in device applications.

Ductile ultrastrong China low activation martensitic steel with lamellar grain structure

The low high-temperature mechanical properties of reduced activated ferrite martensitic (RAFM) heat-resistant steels limit the maximum operating temperature of nuclear fusion reactors. However, it is difficult to improve the strength of the material without reducing its plasticity. In this study we prepared a China low activation martensitic (CLAM) steel with a layered structure through hot rolling followed by low-temperature tempering, which successfully improved its strength and ductility. In addition, we elucidate the ductility mechanisms in such lamellar structural materials. When the strength of the grain boundaries exceeds that of the grains, cracks will continuously extend along the layered grain boundaries, eventually resulting in a delamination fracture mechanism. When the grain strength exceeds that of the grain boundaries, cracks will continuously form through the relative sliding of the grain boundaries, and a large number of small cracks will initiate and propagate longitudinally along the layered boundaries. Both forms of crack propagation cause longitudinal expansion along the layered grain boundaries. The resulting longitudinal extension of cracks markedly diminishes local stress concentration to promote plastic deformation, thereby significantly increasing the ductility of the material. Employing the combination of this delamination ductility mechanism with interface strengthening and precipitation strengthening, the strength of the CLAM steel for nuclear applications is shown to be enhanced by ∼30 % without loss of elongation. The current delamination ductility strategy provides a unique pathway to develop materials with ultrahigh strength and superior ductility at economical material costs.

Machine-Learning-Assisted Development of Carbon Steel With Superior Strength and Ductility Manufactured by Electron Beam Powder Bed Fusion

In this study, based on a novel support vector machine optimization method, a wide processing window for manufacturing defect-free S25C carbon steel by electron beam powder bed fusion (EB-PBF) was identified. Samples with same energy densities exhibited similar microstructures and mechanical properties. One sample showed an optimum strength and elongation combination of 459.3 MPa and 57.6 pct. The pearlite region with irregular cementite particles was the first to crack during deformation, and the cracks gradually expanded into the surrounding area. Ferrite, cellular structures, and pearlite with parallel and straight cementite particles could effectively modulate the deformation by slip and enhance the plasticity of the S25C parts. After quenching, the strength improved to an unprecedented value of 1722.5 MPa owing to the presence of martensite and dislocation entanglements, with an elongation of 16.8 pct. The strength decreased after further tempering, and the plasticity evidently increased, with an optimum strength and elongation combination of 722.7 MPa and 44.2 pct, respectively. The microstructure of tempered sample contained lath martensite, cementite particles, and sparse dislocation lines. These results demonstrate that the current method can serve as a powerful tool for effectively optimizing the high-dimensional parameters of the EB-PBF process to produce carbon steel with excellent mechanical properties.

Shear Strengthening of Reinforced Concrete Beams Using Engineered Cementitious Composites and Carbon Fiber-Reinforced Polymer Sheets

This study evaluates the performance of Reinforced Concrete (RC) beams enhanced in shear using Engineered Cementitious Composites (ECCs) and Carbon Fiber-Reinforced Polymers (CFRPs). The experimental study encompasses fifteen RC beams. This set includes one control specimen and fourteen beams fortified in shear with Externally Bonded (EB) composites. Two of these specimens were enhanced with ECC layers, while the remaining were augmented with combined CFRP-ECC layers. Variables in the test included the ECC layer thickness, matrix type, number of CFRP layers, and strengthening configurations such as full wrapping, vertical strips, and inclined strips. The results indicated that the shear capacity of the fortified beams increased by 61.1% to 160.1% compared to the control specimen. The most effective structural performance was observed in the full wrapping method, which utilized a single CFRP layer combined with either 20 mm or 40 mm ECC thickness, outperforming other techniques. However, the inclined strip method demonstrated a notably higher load-bearing capacity than the full wrapping approach for beams with double CFRP layers paired with 20 mm and 40 mm ECC thicknesses. This configuration also exhibited superior ductility compared to the rest. Furthermore, the experimental shear capacities obtained were juxtaposed with theoretical values from prevailing design standards.

Achieving synergy of strength and ductility in powder metallurgy commercially pure titanium by a unique oxygen scavenger

Excessive interstitial oxygen (O) contamination, usually causing a dramatic loss of ductility, remains a longstanding challenge for titanium (Ti) and its alloys. Here, we propose to solve this critical problem by adding a minor CaC2 oxygen-scavenger via a simple powder metallurgy (PM) pressureless sintering approach. It is found that the surface oxide layer of hydride-dehydride (HDH) Ti powder begins to dissolve into the Ti matrix between 700 °C and 800 °C during the PM sintering process. The incorporation of CaC2 can react with the surface oxide layer (617-676 °C) prior to its active dissolution and form micrometer-sized TiC and nano-sized CaTiO3 particles, significantly refining the α-Ti grains and creating clean and well-bonded interface with Ti matrix. Therefore, the unique oxygen-scavenging effect by CaC2 produces high strength and superior ductility for Ti alloy. Even with an initially high oxygen content (∼4000 ppm), the Ti-0.4 wt.%CaC2 sample still exhibits a high ultimate tensile strength of 621±25 MPa and superior elongation of 29.3±2.6%, respectively. These values correspond to an increase of 17.6% and 301.4% compared to the as-sintered commercially pure titanium (CP-Ti) properties and far exceed the ASTM standard B381 for Grade 4 wrought Ti alloy (550 MPa and 15%) with the same O content. This work offers a novel method to develop high-strength and superior-ductility Ti materials from much more affordable Ti powder.