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Herein, nitrogen-doped tin oxide intercalated activated carbon nanocomposite (N-AC/SnO 2 ) were prepared using hydrothermal strategy and explored as an electrode for capacitive desalination and disinfection. Although tin oxide (SnO 2 ) has good characteristics, the nitrogen must be carefully considered for modifying the characteristics of the carbonaceous materials to improve the performance as an electrode in the CDI process. The characterization of the proposed materials which investigated by XRD, TEM, FE-SEM, XPS and FT-IR affirmed the formation of the nanocomposite. The electrosorption behavior investigated by electrochemical techniques demonstrates that, compared to the specific capacitance of the AC and AC/SnO 2 (207.46 F g −1 and 233.21 F g −1 ), that of the N-AC/SnO 2 is higher at 408.8 F g −1 , and N-AC/SnO 2 exhibits better electrical conductivity. The CDI performance evaluated by batch mode experiments through an applied voltage of 1.2 V in a 50 mg L −1 NaCl aqueous solution shows that the N-AC/SnO 2 electrode introduces a higher electrosorptive capacity of 3.42 mg g −1 , an enhanced desalination efficiency of 61.13%, and good antibacterial performance. Overall, the present study demonstrates that N-AC/SnO 2 has considerable potential as an electrode material for CDI application. [ABSTRACT FROM AUTHOR]

The tensile test criterion to obtain a reliable stress-strain curve from load-displacement data of metallic materials exhibiting twinning or phase transformation was developed especially for environments that do not allow the use of an extensometer. The study shows that neither ASTM E8 / E8M standard specimen nor strip-shaped specimen geometry was appropriate for converting load-displacement data to an actual stress-strain curve; the former exhibited an undesired two-stage yield, while the latter revealed premature fracture. To solve these problems, the relationship between the specimen geometries and load-displacement data was carefully analyzed for dog-bone type specimens having a minimized fillet radius; it was found that the ratio of grip width W gr to gauge width W ga should be higher than the ratio of fracture stress to the first yield stress σ 1 . Otherwise, a second yield always occurred when the stress reached a value close to σ 1 W gr / W ga , obstructing the data analysis to reconstruct the actual stress-strain curve from load-displacement data. Finally, a methodology to verify whether the tensile test satisfied the criterion was suggested in terms of a nominal strain hardening rate. [ABSTRACT FROM AUTHOR]

Microstructure, mechanical properties as well as phase transformation behavior of newly developed Ni 49 Ti 36 Hf 15-x Ta (x=0, 3, 6, 9, 12) high temperature shape memory alloys has been investigated. Ni 49 Ti 36 Hf 15 alloy consists of (Ti,Hf) 2 Ni phase which is brittle and incoherent with the martensite matrix. However, addition of Ta in place of Hf suppresses the brittle (Ti,Hf) 2 Ni phase formation with white Ta rich phase. More than 70% reduction in area has been observed in Ta added Ni 49 Ti 36 Hf 15 high temperature shape memory alloys. The austenitic transformation temperature is well above 200 °C (473 K) for lower Ta concentrations with up to 6 at. %; however; at higher Ta concentrations (i.e. above 9 at. %) decreases significantly. Overall, the addition of Ta greatly influences the hot deformation behavior and high temperature shape memory properties of Ni 49 Ti 36 Hf 15 alloy. The present paper discusses the detailed investigation on Ni 49 Ti 36 Hf 15-x Ta (x=0, 3, 6, 9, 12) high temperature shape memory alloys. [ABSTRACT FROM AUTHOR]

The mechanisms of dynamic recrystallization (DRX) in a 50Ti-47Ni-3Fe alloy are studied using compression tests at temperatures of 1023–1323 K with strain rates of 0.01–10 s −1 , and the resulting stress-strain curves are used to construct an Arrhenius equation with a Zener-Hollomon parameter (Z). The relationship between this Z parameter and stress, and its effect on the subgrain size are discussed. With the help of electron backscatter diffraction (EBSD), the development of recrystallizing grain boundaries is tracked in deformed grains with different grain orientation spread (GOS) values. Continuous dynamic recrystallization (CDRX) is subsequently confirmed by evidence of the conversion of low-angle boundaries (LAGBs) into high-angle boundaries (HAGBs). Grain boundary sliding (GBS) and HAGB migration are therefore considered secondary mechanisms under high-Z (ln Z > 29) and low-Z (ln Z < 23.5) conditions, but CDRX is confirmed as the dominant DRX mechanism. [ABSTRACT FROM AUTHOR]

Bulk nanocrystalline ( d = 20–40 nm) Ni–Ti shape memory alloy was produced via cold marforming, followed by optimum post-heat treatment. The total accumulative strain ( ε ∼ 0.7) during the process was much lower than that typically imposed during severe plastic deformation operations (i.e., 5 ≤ ε ≤ 12). In-situ heating transmission electron microscopy revealed that the present process was effective in promoting static recrystallization and limiting grain growth. The nanocrystalline alloy exhibited enhanced shape memory behaviors. [ABSTRACT FROM AUTHOR]

Plastic anisotropy and associated deformation mechanisms of rolling textured high purity alpha phase titanium were investigated by carrying out uniaxial compression tests along the three featured directions, the rolling direction (RD), normal direction (ND) and transverse direction (TD), in combination with an electron backscatter diffraction measurement and a Schmid factor (SF) analysis. The results revealed that the specific crystallographic feature of the material, caused by rolling texture, influences the activities of dislocation slips and twinning by affecting their SF, and this significantly varies with the loading direction, consequently leading to anisotropic deformation. The material yielding was dominated by dislocation slips, and the change of yielding mechanism with the loading direction (prismatic slip for the RD and TD, and basal slip for the ND) gave rise to yielding anisotropy. As the material deformed beyond the yielding point, deformation twins took place and played a decisive role in the deformation. The twinning characteristics including types of twins, morphology, twin area fraction with strain and related texture modification significantly varied with the loading direction, and this had a completely different effect on strain hardening behavior, thereby causing deformation anisotropy. [ABSTRACT FROM AUTHOR]

Highlights: [•] We have investigated the effect of cold working on the martensitic transformation. [•] The TiNi wire showed multiple-stage martensitic transformation behavior. [•] The multiple-stage transformations originated from microstructural instability. [ABSTRACT FROM AUTHOR]

Highlights: [•] Low temperature milling effectively decreased grain size. [•] Low temperature milling was very effective in oxide particle size reduction. [•] Homogeneous distribution of Y2O3 was very important for fine microstructure. [•] Tensile strength was significantly increased by low temperature milling. [Copyright &y& Elsevier]

Highlights: [•] Flow softening of Ti–6Al–4V with a lamellar microstructure was modeled. [•] Flow softening originated from colony rotation and alpha particle coarsening. [•] The model provided an accurate prediction of the flow response during hot working. [ABSTRACT FROM AUTHOR]

In this study, a Ti–3Mo–3Cr–2Fe–2Al alloy (α + β Ti alloy) showing twinning- and transformation-induced plasticity was investigated. The existence of α yielded fine-grained β phases. The β grains, comprising low-angle boundaries, produced a high yield strength of 737 MPa despite the low α volume percentage. Martensite and twin interactions with these boundaries induced local stress concentrations. These led to a high work-hardening rate compared to that in a full β microstructure. The α + β Ti alloy showed an excellent combination of strength (1324 MPa) and ductility (0.37). Image 1 • α+β Ti–3Mo–3Cr–2Fe–2Al alloy showed the twinning- and transformation-induced plasticity. • The existence of α developed sub-grained structure and yielded the grain refinement. • Both twin and martensite impinged the low angle boundaries resulting in local stress concentration. • The sub-grained structure caused by α exhibited an excellent tensile properties. [ABSTRACT FROM AUTHOR]

Abstract In this study, the deformation mechanism of a metastable Ti-4Al-4Fe-0.25Si-0.1O alloy was investigated via ex-situ electron backscattering diffraction (EBSD) and field-emission transmission electron microscopy (FE-TEM). A stress-induced α′-martensitic transformation occurred from the retained β phase. New variants of α′-martensite were nucleated and grew in the transformed α′-martensite under increasing levels of applied stress. Microstructural observations revealed that the orthorhombic nanodomains were sheared in the prior α′-martensite; these sheared nanodomains contributed to the formation of different variants of α′-martensite. This additional martensitic transformation resulted in an excellent combination of strength (ultimate tensile strength; UTS: 1340 MPa) and ductility (30%). Highlights • Ti-4A-4Fe-0.25Si alloy showed the stress-induced α′-martensite transformation. • Randomly distributed nano-domain was sheared by the martensite transformation. • The sheared domains were transformed to secondary martensite. • This stepwise transformation exhibited an excellent tensile properties. [ABSTRACT FROM AUTHOR]

In this study, the effect of phase conditions on the tensile behaviors of Ti-Cu alloys with Cu contents of 0, 10, 20, and 30 wt% is investigated by controlling the annealing temperature. An in-depth characterization of the alloy microstructure is performed using scanning electron microscopy and transmission electron microscopy. The results suggest that the mechanical properties of the Ti-Cu alloys are strongly affected by the Cu content in α lath, which is dependent on the volume of Ti 2 Cu rather than Ti 2 Cu itself. A high volume of Ti 2 Cu reduces the Cu content in α lath, resulting in high elongation and low strength. Ti 2 Cu has superior antibacterial properties when compared with that of the Cu-supersaturated α lath. This study provides new insights into the design of Ti-Cu alloys for application as a biomaterial. • Ti-Cu alloys were used to study effect of phase condition on tensile behavior. • Cu content in α lath strongly influences the mechanical properties. • High Cu content in α lath increased the strength but decreased the ductility. • Equiaxed Ti 2 Cu + α lath is beneficial for high ductility and antibacterial ability. [ABSTRACT FROM AUTHOR]

Highlights: [•] We fabricated TiNi thin films using advanced multi-target sputtering system. [•] We examine martensitic transformation of TiNi thin films by heat-treatment. [•] Composition effect on martensitic transformation of TiNi films was also examined. [•] Ideal heat-treatment condition of TiNi thin films for application was reported. [ABSTRACT FROM AUTHOR]

The phase stability of near/metastable β-type Ti–Cr-(Mn) alloys with 4.06–13.46 wt% molybdenum equivalent fabricated by rapid solidification process were evaluated using several parameters, i.e. bond order, metal d -orbital energy level and molybdenum equivalent. The microstructural evolution of the near/metastable β-type Ti–Cr and Ti–Cr–Mn alloys was systematically investigated by using optical and transmission electron microscopies. With increasing molybdenum equivalent value in the Ti–Cr-(Mn) alloys, α" martensitic transformation and precipitation of athermal ω phase were strongly suppressed during rapid cooling. Based on microstructural investigation, the β phase stability of the alloys was evaluated using the phase stability index diagram using bond order, metal d -orbital energy level parameters. Moreover, the microstructural evolution depending on the phase stability of Ti–Cr-(Mn) alloys strongly affected to mechanical properties and trade-off behavior between strength and plasticity. Based on these microstructural evolutions and mechanical properties of the Ti–Cr-(Mn) alloys, the phase stability and a relationship between phase stability and mechanical properties of near/metastable β-type titanium alloys were systemically investigated. Image 1 • Phase stability of Ti–Cr-(Mn) alloys was evaluated by theoretical parameters and systematic investigation. • β phase stability strongly affected martensitic transformation and microstructure. • Additional phase boundaries for α" and ω ath phases were added in B o ‾ − M d ‾ phase stability index diagram. • Ti–Cr(Mn) alloys revealed large trade-off behavior on mechanical properties. • Linear relationship between yield strength and [Mo] eq value was identified. [ABSTRACT FROM AUTHOR]

We used selective laser melting (SLM) to produce a three-dimensional specimen of pure Ti and found that an equiaxed grain structure and weak crystallographic texture could be achieved simultaneously via subsequent heat treatment. These traits have never been attained simultaneously in pure Ti prepared by traditional methods such as casting and rolling. This remarkable achievement was possible because recrystallization occurred during heat treatment without plastic deformation; such deformation introduces stored energy that drives recrystallization but inevitably causes a strong texture to develop. The occurrence of recrystallization was attributed to unique features of the SLM process including a very high cooling rate and repetitive layer stacking. These features generated considerable stored energy by affecting solidification and the β → α phase transformation. Steep in-grain orientation gradients and a fine lath structure also contributed to the activation of recrystallization by facilitating recrystallization nucleation. The heat-treated specimen showed tensile properties with significantly reduced anisotropy. This finding will provide new strategies for developing isotropic metallic materials and may introduce new applications of SLM. • A three-dimensional specimen of pure Ti was produced using selective laser melting. • Both equiaxed structure and weak texture were achieved by subsequent heat treatment. • These traits cannot be attained simultaneously by traditional manufacturing methods. • This desirable ability of SLM originates from unique features of SLM process. • The heat-treated sample had significantly reduced anisotropy in tensile properties. [ABSTRACT FROM AUTHOR]

The low-cost β-titanium alloys, Ti-Cr-Al-Si, have been designed by the addition of a commercial Al-based die-cast alloy (ADC12, Al 87.38 Cu 0.95 Si 10.65 Mg 0.27 Zn 0.30 Fe 0.32 Mn 0.11 Cr 0.02 in at.%) containing Si content. The microstructural investigation on Ti 84-x Cr 16 (ADC12) x (x = 6, 16 at.%) alloys exhibited that the addition of 6 at.%ADC12 completely dissolved in the β-Ti phase, and exhibited reasonable yield strength by solid solution hardening of the β-Ti phase with large plasticity. The addition of 16 at.%ADC12 effectively reduces the cost of the β-titanium alloys and induces microstructural evolution with formation of Ti-silicide. The β-Ti phase containing high content of solutes and the very fine Ti 5 Si 3 phase that segregated in the interdendritic regions, due to Si solute partitioning during dendritic solidification, mediates outstanding tensile mechanical properties (1015 MPa in yield strength and 17.5% in elongation). These results reveal that the alloy designs using the commercial materials containing various solute elements can facilitate the development of the competitive low-cost β-titanium alloys with excellent mechanical properties. Image 1 • Low-cost β-titanium alloys were designed using cheap commercial ADC12 alloy. • Tensile properties of the alloys improved significantly by addition of ADC12 alloy. • An addition of ADC12 alloy facilitated two strengthening mechanisms. • Solid solution strengthening induced by high Al content dissolved in β-Ti phase. • Precipitation hardening induced by fine Ti-silicide formed during dendritic solidification. [ABSTRACT FROM AUTHOR]

Abstract Bimodal grain structures are often produced in a metal by employing severe plastic deformation followed by low-homologous-temperature annealing (≤0.4 T m , where T m is melting temperature). Here, a bimodal grain structure was achieved in a Co–20Cr–15W–10Ni–C superalloy via moderate cold rolling (strain ≈0.3) and ultrahigh-homologous-temperature annealing (≥0.8 T m). During annealing, carbide-assisted heterogeneous static-recrystallization played a key role in forming the bimodal grain structure. A 40% increase in combined strength and ductility was observed. Graphical abstract Image 1 Highlights • A bimodal grain structure was achieved in a superalloy without severe deformation. • Cold rolling and ultrahigh-homologous-temperature annealing were carried out. • Carbide-assisted heterogeneous static recrystallization occurred during annealing. • The bimodal grain structure provided 40% higher σ × ε values than uniform grains. [ABSTRACT FROM AUTHOR]

Abstract In recent years, capacitive deionization (CDI) has attracted intensive research due to its environmentally-friendly nature and low power requirement. Although the characteristics of titania (TiO 2) and zirconia (ZrO 2) are almost the same, ZrO 2 has not attracted the same attention since the characteristics of the carbonaceous material need to be modified to enhance its performance as an electrode in CDI cells. In this study, the wettability and electrochemical behavior of activated carbon (AC), as a widely used, effective, and inexpensive material, was distinctively improved by doping with zirconia nanoparticles. The introduced AC/ZrO 2 nanocomposite was fabricated using the alkaline hydrothermal method. Investigation of the surface morphology, phase and crystallinity by SEM, TEM, XPS, and XRD demonstrated the successful doping of AC by zirconia nanoparticles. Interestingly, the wettability measurement showed excellent enhancement, since the water contact angles of pristine and doped AC are 45° and 148°, respectively. The electrochemical experiments demonstrated that the synthesized composite (AC/ZrO 2) has a specific capacitance of 282.8 F g−1, which is higher than that for AC (207.5 F g−1). Due to the significant improvement in wettability and specific capacitance, the desalination performance and the salt ion electrosorption capacity were also enhanced: 40.4% and 68.5%, and 2.82 and 4.79 mg/g for AC and AC/ZrO 2 , respectively. Moreover, the introduced AC/ZrO 2 revealed 99% remaining desalination retention suggesting high stability. Overall, this study demonstrates ZrO 2 is an effective, stable, and environmentally safe material for improving the performance of carbonaceous CDI electrodes. Graphical abstract Image 1 Highlights • ZrO 2 NPs/AC is introduced as effective CDI electrode material. • The salt removal efficiency has been improved to 68.5%. • Good performance is due to improving the specific capacitance. [ABSTRACT FROM AUTHOR]

The effect of interlayer cooling in directed energy deposition on the microstructure and mechanical properties of two titanium alloys (Ti–6Al–4 V and Ti–2.5Fe–4.5Al–0.25Si) was investigated in this study. On the one hand, the general process of directed energy deposition provided sufficient time for element partitioning, resulting in the formation of the isothermal ω. On the other hand, interlayer cooling interfered with element partitioning and isothermal ω formation. It induced the formation of the supersaturated α. The isothermal ω or supersaturated α, generated based on the fabrication conditions, significantly influenced the mechanical properties of these alloys. The higher the β-phase stability of the alloy, the greater is the change in its mechanical properties depending on the fabrication conditions. This study provides guidelines for the design of new alloys manufactured using directed energy deposition. • Two Ti alloys were used to study effect of interlayer cooling on tensile behavior. • Supersaturated α and isothermal ω strongly influences the tensile properties. • Interlayer cooling generated the supersaturated α and increased the strength. • General fabrication generated isothermal ω and decreased the ductility. [ABSTRACT FROM AUTHOR]

Zinc oxide (ZnO) nano flowers uniformly attached to the surface of Molybdenum disulfide (MoS 2 ) sheet were successfully prepared via a simple facile one pot hydrothermal method. The morphology and microstructure of the prepared samples was characterized using field – emission scanning electron microscopy (FE-SEM), Transmission electron microscopy (TEM), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR), and photoluminescence (PL) spectroscopy. The Brunauer-Emmett-Teller (BET) surface area was determined using physical and chemical analyzer. The characterization results showed that the flowers like ZnO micro-structures were uniformly attached to the surface of MoS 2 . The as-prepared MoS 2 /ZnO composite showed enhanced photocatalytic activity and considerable stability for the photo degradation of phenol red as compared with pure MoS 2 and ZnO under both UV and visible light irradiation. Such an enhancement of photo degradation capability was ascribed to the synergistic effect between the flowers-shaped ZnO particles and sheet-like structure of MoS 2 , which boost the migration efficiency of photo-induced electrons and hinder electron-hole recombination rate. It was also found that the amount of MoS 2 in the composite has a significant effect on the degradation activity. Moreover, the antibacterial activity test towards the gram negative Escherichia-coli showed that the MoS 2 /ZnO composite has better antibacterial properties compared to pure ZnO and MoS 2 . [ABSTRACT FROM AUTHOR]

Highlights: [•] Significant particle/grain size refinement of both Y2O3 and Fe-alloy powders by cryomilling. [•] Mechanisms of fragmentation/dissolution of Y2O3 during cryomilling were suggested. [•] The effect of cryomilling on residual microstrain was found. [•] Increased interstitial elements contamination during cryomilling was found. [ABSTRACT FROM AUTHOR]

Abstract: We report an ethylene glycol-mediated one-pot synthesis with post-annealing treatment of uniformly-distributed TiO2 nanospheres on nanosheet-based α-Fe2O3 (hematite) hierarchical flowers. The present samples were characterized by several analytical techniques including field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and thermogravimetric analysis (TGA). Enhancement in photocatalytic efficiency with magnetically-assisted recovery could be realized in the present TiO2/α-Fe2O3 nanocomposites due to the high crystallinity of anatase TiO2 and the recyclability was resulted from ferromagnetics of hematite. [Copyright &y& Elsevier]

Laser-powder bed fusion (L -PBF) is being increasingly employed in the fabrication of commercially pure titanium (CP-Ti) components for biomedical applications. However, L -PBF-manufactured CP-Ti parts typically exhibit high strength and reduced ductility owing to the formation of acicular α′ martensite. It is essential to decompose the acicular α′ martensite into the equilibrium α phase through post-heat treatments to achieve superior mechanical properties. In this study, post-heat treatments were applied to L -PBF-fabricated CP-Ti Gr. 1−Gr. 4 samples. The microstructures of the as-fabricated CP-Ti samples were dominated by acicular α′ martensite, which exhibited high strength (>800 MPa) but low ductility (<20%). Full annealing resulted in the formation of equiaxed grains and the disappearance of the columnar structures in the CP-Ti samples. The equiaxed grains contributed to high ductility (>30%) in the Gr. 1 and Gr. 2 samples, but low ductility (<20%) in the Gr. 3 and Gr. 4 samples. This low ductility is associated with the formation of grain-boundary β layers. Well-designed partial annealing led to the formation of bimodal structures consisting of both equiaxed and fine lamellar grains. This specific structure provides both a high strength (>700 MPa for Gr. 2 and,>850 MPa for Gr. 4) and high ductility (>35% for Gr. 2 and Gr. 4), which are superior to those of the samples processed under full annealing conditions. Therefore, tailoring the bimodal structure in the L -PBF-manufactured CP-Ti for both high strength and ductility is promising for biomedical applications. • Bulk CP-Ti Gr. 1−Gr. 4 were produced using selective laser melting. • As-fabricated CP-Ti exhibited high strength and low ductility. • Equiaxed and bimodal structure were achieved by post-heat treatment. • The bimodal structures provided higher σ × ε values than equiaxed grains. [ABSTRACT FROM AUTHOR]

• ANN model corrected flow stress of WAAM Ti-6Al-4V alloy used to construct processing map. • The self deformation activation energy were significantly different in the α+β and β phase region. • The high fraction and nearly equiaxed DRX α obtained at the high efficiency region of the processing map. • The hot forged sample at optimum condition show weak texture, high strength and elongation. Recently, the hybrid method has been developed in which wire and arc additive manufacturing (WAAM) use to produce the near net shape preform for the single-step hot forging process. The hybrid method overcomes the defects and anisotropic properties of WAAM processed preform and produce the net shape of the component with better mechanical properties. This study investigates the hot deformation behavior and mechanical properties of WAAM Ti-6Al-4V alloy containing widmantatten microstructure (0.34 – 0.48 µm) produced by the hybrid method. Hot deformation tests were conducted in the temperature range 700–1000 °C and strain rate range 0.01 s−1 – 10 s−1 up to the height reduction of 60%, using the thermal-mechanical simulator gleeble-3800. The artificial neural network model (ANN) has been developed to correct the non-isothermal flow curve at finer intervals of experimental conditions. The microstructural studies were carried out at various regions using a developed processing map. The microstructures show an instability region at a high strain rate and lower temperature, associated with flow localization and lamellae kinking. At the same time, the high efficiency and stable regions are related to dynamic recrystallization in the temperature range 900–950 °C at a strain rate below 1 s−1. The self-deformation activation energy in the α + β and β phase regions was 308.7 kJ/mol and 493.2 kJ/mol, respectively. The forged sample at 920 °C and strain 0.6, 0.8, and 0.9 show high strength, elongation, and weak texture compared to the received and stress relieved sample. [ABSTRACT FROM AUTHOR]

• Optimal process variables for Ti–4Al–2Fe–(0−4)Mn–0.18O were determined using ANN. • A Mn content of 1.4 wt% and solution treatment temperature of 883 °C were optimal. • Dynamic grain refinement dominates the properties of the novel TRIP alloy system. • The optimized cost effective alloy offers superior mechanical properties. Transformation-induced plasticity (TRIP) Ti alloys are promising structural materials that offer high strength and ductility. However, these alloys often include heavy, expensive, and high-melting-point β-stabilizing elements such as V, Nb, Mo, and W. Herein, an artificial neural network (ANN) was used to develop a Ti–Al–Fe–Mn-based TRIP alloy comprising lighter and/or cheaper elements. The ANN model was trained with 30 experimental tensile datasets for heat-treated (830–920 °C) Ti–4Al–2Fe– x Mn (x = 0–4 wt%) alloys, and used to generate 400 tensile datasets with more finely tuned composition and temperature intervals. Based on the predicted data, an 883 °C-heat-treated Ti–4Al–2Fe–1.4Mn alloy was produced (conditions not used in the training datasets), which exhibited ultra-high specific strength (289 MPa·cm3/g) and high elongation (34%). Thus, the ANN approach successfully led to the development of a new alloy while minimizing the number of labor-intensive and time-consuming experiments. [ABSTRACT FROM AUTHOR]

Biomedical implant material simultaneously requires high yield strength and low Young's modulus. The lower boundary for the YM of Ti–13Nb–13Zr alloys is regarded to be approximately 65 GPa, which limits further improvement in their mechanical compatibility. This study proposes a novel process of cold caliber rolling to break this limit and decrease YM to 47 GPa, which is the bare minimum value since the development of this alloying system. As a result, the developed alloy exhibits a mechanical compatibility similar to those of most advanced β -Ti alloys but with a significantly lower amount of high-cost alloying elements. This study attributed the mechanical improvement to three mechanisms based on microstructural characterizations. Manufacturing advantages of the suggested method were discussed as well. Image 1 • Cold caliber rolling of Ti–13Nb–13Zr achieved markedly low Young's modulus. • Such a low Young's modulus is attributed to the formation of the α″ martensite phase. • Cold caliber rolling provides benefits in cost-saving and manufacturing advantages. [ABSTRACT FROM AUTHOR]

The present study describes the influence of β stabilizers (namely Fe and Cr) on the microstructural evolution and mechanical behavior of Ti–6Al–4V alloy fabricated by direct energy deposition. As the β stabilizer content increases from 1 to 4 wt%, the coarse columnar-grained morphology typical of additively manufactured Ti–6Al–4V is significantly refined, with a columnar-to-equiaxed transition. Furthermore, reheating of the deposited layers by the deposition of overlaying layers during fabrication induces an element partitioning effect, resulting in the formation of fine-grained α and isothermal ω. Hence, the heat profile during direct energy deposition resembles conventional solution and aging treatments. In addition, increasing the amount of β stabilizer steadily increases the room temperature strength of the Ti–6Al–4V alloy. The alloy with 4 wt% Fe showed the maximum strength, of ∼1.5 GPa. • The columnar-to-equiaxed transition of microstructure was achieved in the direct energy deposited Ti–6Al–4V alloy with the addition of Fe and Cr. • The maximum room temperature strength of the Ti–6Al–4V with 4 wt% Fe alloy reaches ∼1.5 GPa. • The reheating phenomenon caused by deposition of overlying layers during direct energy deposition resembles conventional solution and aging treatments. • With an increasing amount of β stabilizer, the phase constituents in the Ti–6Al–4V alloy changed from αʹ.→ αʹ+α+ω+β → α+ω+β [ABSTRACT FROM AUTHOR]