Differing from the statically precipitated grain boundary α(GBα) that holds Burgers Orientation Relationship(BOR) with adjacent β grains, in this work, it was found that over 97.77 % of the dynamically precipitated...
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Differing from the statically precipitated grain boundary α(GBα) that holds Burgers Orientation Relationship(BOR) with adjacent β grains, in this work, it was found that over 97.77 % of the dynamically precipitated GBαs do not hold BOR with either side of the adjacent β grains in hot-forged Ti-652 titanium alloy. The evolution of GBα orientation was decoupled as dynamic precipitation and annihilation, which was quantitatively distinguished by defining three misorientation angles: the deviation form BOR(ω), the misorientation between adjacent β grains(θ) and the misorientation between non-BOR GBαs(θ'). During the entire hot forging, an adequate dynamic precipitation produces piecewise continuous and slender GBαs with ω <10°typically, manifesting as θ <25°but θ'>45°. Oppositely, a sufficient annihilation leads to the dynamic globularization of GBαs and increase of ω with θ≥25°but mainly θ'≤45°. Dynamic precipitation was driven by the intrinsic BOR preference of GBαs, while annihilation attributed to grain growth and rotation caused by accumulated plastic deformation. Deciphering the dynamic precipitation and annihilation of GBα provides a quantitative criterion to tailor microstructures and mechanical properties in the future.
With the further requirements of electronic products and powered vehicles,the development of a new generation with low-voltage and high-capacity anode materials is crucial for lithium-ion batteries(LIBs).Transition me...
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With the further requirements of electronic products and powered vehicles,the development of a new generation with low-voltage and high-capacity anode materials is crucial for lithium-ion batteries(LIBs).Transition metal phosphides,especially cobalt phosphide(CoP)composites,have become a research hotspot for LIBs anode materials in recent years due to their high theoretical specific capacity,low polarization,and suitable voltage *** review first systematically discusses the lithium storage mechanism and preparation methods of CoP in current ***,the applications of CoP anode materials in LIBs are categorically reviewed,including the composites of CoP with various types of carbon materials and ***,the challenges and future development directions of CoP anode materials are summarized to provide guidance for further improving the lithium storage performance of CoP and its practical applications.
High-strength titanium alloys(HS-TAs), particularly those with an ultimate tensile strength exceeding 1100 MPa,play a crucial role in aerospace and other advanced engineering fields. However, faced with the continuous...
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High-strength titanium alloys(HS-TAs), particularly those with an ultimate tensile strength exceeding 1100 MPa,play a crucial role in aerospace and other advanced engineering fields. However, faced with the continuously evolving industrial landscape and increasingly complex application environments, research and development of HS-TAs are encountering unprecedented challenges. This paper provides a review of significant research advancements in the field of HS-TAs in recent years, with a special focus on the latest achievements in microstructural design, processing technology, and strengthening mechanisms. Initially, the paper offers an integrated assessment of how alloying and non-alloying elements precisely control the distribution and morphology of α andβ phases at the microscale, and their impact on the mechanical properties of titanium alloys. Subsequently, from the perspectives of plastic deformation and microstructure regulation, the paper delves into the contributions of various mechanisms such as solid-solution strengthening, grain boundary strengthening, and precipitation strengthening, to the enhancement of high-strength titanium alloy performance. Additionally, the article compares and analyzes the effects of different heat treatments and mechanical processing techniques on the microstructure and overall performance of HS-TAs. Finally, the paper presents future research directions and potential applications of these alloys in some key areas, aiming to provide a theoretical foundation and practical guidance for the development of advanced structural materials with high strength and optimized ductility.
Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstr...
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Equal channel angle pressing is recognized for its ability to refine alloy grains and alter grain orientation, thereby achieve better mechanical performance of the magnesium alloy. This study investigates the microstructures,dynamic recrystallization mechanism, texture development, and mechanical performance of GW94K(Mg–8.7Gd–4.18Y–0.42Zr wt. %) Mg alloy following ECAP-4 passes at 400°C and 3 mm/min. Results show that when high-temperature deformation is undertaken, twin formation is suppressed while dislocation slip is facilitated, increasing dislocation density during deformation. Following ECAP deformation, the sample displayed higher fracture elongation, TYS, and UTS than the as-solutioned GW94K alloy. In particular, the GW94K alloy performed well mechanically after ECAP-4 passes, with an ultimate TYS of 231 MPa, an UTS of 290 MPa, and an elongation of 14.8 %. DDRX and shear bands induce CDRX, both of which are important in plastic deformation. as well as in modifying microstructure and grain orientation during ECAP deformation.
Scholars aim for the improved impedance matching (Z) of materials while maintaining their excellent wave absorption properties. Based on the hydrolysis characteristics of isopropyl titanate, a simple preparation proce...
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Scholars aim for the improved impedance matching (Z) of materials while maintaining their excellent wave absorption properties. Based on the hydrolysis characteristics of isopropyl titanate, a simple preparation process for the coating of carbonyl iron powder(CIP) with TiO_(2) was designed. Given the TiO2coating, the Z of the CIP@TiO_(2) composite was adjusted well by decreasing the dielectric constant. Moreover, the interfacial polarization of CIP@TiO_(2) was enhanced. Ultimately, the electromagnetic-wave (EMW) absorption property of the CIP@TiO_(2)composite was improved substantially, the minimum reflection loss reached-46.07 dB, and the effective absorption bandwidth can reach 8 GHz at the composite thickness of 1.5 mm. Moreover, compared with CIP, the oxidation resistance of CIP@TiO_(2)showed remarkable improvement. The results revealed that the oxidation starting temperature of CIP@TiO_(2) as about 400℃,whereas the uncoated CIP had an oxidation starting temperature of approximately 250℃. Moreover, the largest oxidation rate temperature of CIP@TiO_(2) increased to around 550℃. This work opens up a novel strategy for the production of high-performance EMW absorbers via structural design.
This paper presents a systematic investigation of the microstructure and magnetocaloric properties of melt-extracted Sm_(20)Gd_(20)Dy_(20)Co_(20)Al_(20)high-entropy *** fabricated wires exhibited an amorphous structur...
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This paper presents a systematic investigation of the microstructure and magnetocaloric properties of melt-extracted Sm_(20)Gd_(20)Dy_(20)Co_(20)Al_(20)high-entropy *** fabricated wires exhibited an amorphous structure,and the temperature interval of the undercooled liquid AT was 45 *** microwires underwent a second-order magnetic transition from a ferromagnetic to a paramagnetic state near the Curie temperature(T_(C)=52 K),The maximum magnetic entropy change(-ΔS_M^(max)),the relative cooling power and the refrigeration capacity reached 6.34 J·kg^(-1)·K^(-1).422.09 J·kg^(-1)and 332.94 J·kg^(-1),respectively,under a magnetic field change of 5 *** addition,the temperature-averaged entropy changes with two temperature lifts(3 and 10 K)were 6.32 and 6.27 J·kg^(-1)·K^(-1),*** good magnetocalorie performance highlights the significant potential for the Sm_(20)Gd_(20)Dy_(20)Co_(20)Al_(20)microwires to be used as magnetic refrigerant materials in low-temperature region *** work will serve as a valuable reference for future investigations on low-temperature high-entropy magnetocaloric materials.
Achieving a delicate synergy between mechanical robustness and antifouling attributes in coatings re-mains a formidable challenge for marine *** by the assembly of nacre,we present a novel approach to fabricate a nacr...
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Achieving a delicate synergy between mechanical robustness and antifouling attributes in coatings re-mains a formidable challenge for marine *** by the assembly of nacre,we present a novel approach to fabricate a nacre-like metallic *** coating comprises an amorphous matrix with excellent anti-corrosion and anti-wear properties,as well as Cu-rich 3D interconnected channels for antifouling *** coating is produced by high velocity oxygen fuel(HVOF)thermal spraying of surface-modified Fe-based amorphous powders with a *** resulting coating exhibits excep-tional mechanical robustness,including high resistance to erosion,abrasion,and impact,surpassing con-ventional polymer antifouling ***,the controlled Cu+leaching capability of the in-situ constructed 3D interconnected diffusion channels,facilitated by the Cu-rich intersplats,contributes to the remarkable antifouling *** includes nearly 100％resistance to bacterial adhesion after 1 day of immersion and over 98％resistance to algal attachment after 7 d of immersion,resulting in a prolonged service ***,even after 200 cycles of wear damage,the Cu-modified amorphous coating still maintains its excellent antifouling *** Cu-rich intersplats play a critical role in transporting and sustainably leaching Cu ions,thereby accounting for the outstanding antifouling ***,we aim to advance the design of high-performance coatings suited for diverse marine applications,where both the mechanical robustness and antifouling properties are essential.
In our current study,the impact of pre-creep treatment at 300 ℃ and 560 MPa for 1000 h on the sub-sequent creep behavior and properties at an elevated temperature of 400 ℃ have been *** characterization of the resul...
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Amorphous alloys, i.e., metallic glasses, combine high strength, hardness, excellent wear and corrosion resistance, and unique thermoplasticity due to their short-range ordered but long-range disordered glassy structu...
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Amorphous alloys, i.e., metallic glasses, combine high strength, hardness, excellent wear and corrosion resistance, and unique thermoplasticity due to their short-range ordered but long-range disordered glassy structures. However, critical size constraints limit their applications in advanced fields such as electrocatalysis, sensing, and complex devices. Here we report a novel lattice metamaterial fabricated by conformally depositing NiNbSn amorphous alloy coatings onto three-dimensional(3D)-printed polymer scaffolds with a cubic micro-nano lattice template. The cubic lattice design enables efficient stress transfer and uniform strain energy distribution,minimizing stress concentration. Meanwhile, the NiNbSn coating, featuring amorphous and nanocrystalline components, further enhances the structure through size hardening. The resulting hybrid polymer/alloy lattice shows excellent mechanical properties and an exceptional energy absorption capacity. Furthermore, coating the hybrid lattice with a NiMoPB glassy film results in a 3D nano-micro electrode for glucose detection, achieving a sensitivity of 13 times higher than that of the castcounterpart. Our strategy opens a new path to fabricating hybrid polymer/MGs micro-nano lattice structures with excellent mechanical and electrochemical performance, broadening the potential applications of metamaterials.
The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were *** compression and tenssion tests were carried out by Gleebl...
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The hot deformation behaviors of sulfur-containing gear steel 20MnCr5 containing three different contents of Nb and B(0,0.021%Nb,and 0.024%Nb-0.0022%B)were *** compression and tenssion tests were carried out by Gleeble3800 at the austenite region from 850 to 1150℃and the adverse effects of Nb and B were analyzed by the fracture,microstructure and precipitate *** compression tests showed that the proportions of instable area in hot processing maps of 0.021%Nb and Nb-B steels were higher and the deformability of Nb free steel was *** tensile deformation experiments showed that the reduction areas of Nb free,0.021%Nb and Nb-B steels were 92%-99%,84%-98%and 67%-97%,*** addition of Nb or Nb and B inhibited the dynamic recrystallization during hot deformation,and consequently,more deformed grains were then formed in 0.021%Nb and Nb-B steels thus to obtain the microstructure with worse uniformity and then deteriorate the *** addition,the interaction between inclusions and microalloyed elements was also *** particles of 0.021%Nb and Nb-B steels dynamically precipitated during deformation and precipitated together with MnS thus to worsen the deformability,resulting in the decrease of reduction area.
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