Started in 1985 Semimonthly
ISSN 1005-0302
CN 21-1315/TG
Impact factor:6.155

The journal has been awarded the excellent periodical in China, and its articles are covered by SCI, EI, CA, SA, JST, RJ, CSA, MA, EMA, AIA etc., PASCAL web. ISI web of Science,SCOPUS.

  Current Issue
      15 January 2021, Volume 61 Issue 0 Previous Issue   
    For Selected: View Abstracts Toggle Thumbnails
    Research Article
    Hot deformation behavior and processing map development of AZ110 alloy with and without addition of La-rich Mish Metal
    Qiyu Liao, Yanchao Jiang, Qichi Le, Xingrui Chen, Chunlong Cheng, Ke Hu, Dandan Li
    J. Mater. Sci. Technol., 2021, 61 (0): 1-15.  DOI: 10.1016/j.jmst.2020.04.064
    Abstract   HTML   PDF

    In order to compare the workability of AZ110 alloy with and without addition of La-rich Mish Metal (MM), hot compression tests were performed on a Gleeble-3500D thermo-mechanical simulator at the deformation temperature range of 473-623 K and strain rate range of 0.001-1 s-1. The flow stress, constitutive relation, DRX kinetic model, processing map and microstructure characterization of the alloys were investigated. The results show that the flow stress is very sensitive to deformation temperature and strain rate, and the peak stress of AZ110LC (LC = La-rich MM) alloy is higher than that of AZ110 alloy. The hot deformation behavior of the alloys can be accurately predicted by the constitutive relations. The derived constitutive equations show that the calculated activation energy Q and stress exponent n for AZ110 alloy are higher than the calculated values of AZ110LC alloy. The analysis of DRX kinetic models show that the development of DRX in AZ110LC alloy is earlier than AZ110 alloy at the same deformation condition. The processing maps show that the workability of AZ110LC alloy is significantly more excellent than AZ110 alloy and the microstructures are in good agreement with the calculated results. The AZ110LC alloys can obtain complete DRX microstructure at high strain rate due to its higher stored energy and weak basal texture.

    Figures and Tables | References | Related Articles | Metrics
    Effect of interlayer addition on microstructure and mechanical properties of NiTi/stainless steel joint by electron beam welding
    H. Niu, H.C. Jiang, M.J. Zhao, L.J. Rong
    J. Mater. Sci. Technol., 2021, 61 (0): 16-24.  DOI: 10.1016/j.jmst.2020.05.043
    Abstract   HTML   PDF

    NiTi/Stainless Steel (SS) sheets have been welded via a vacuum electron beam welding process, with three methods (offsetting electron beam to SS side without interlayer, adding Ni interlayer and adding FeNi interlayer), to promote mechanical properties of the NiTi/SS joints. The joints with different interlayers are all fractured in the weld zone near the NiTi side, which is attributed to the enrichment of intermetallic compounds including Fe2Ti and Ni3Ti. The fracture mechanisms of different joints are strongly dependent on the types of interlayers, and the joints without interlayer, adding Ni interlayer and adding FeNi interlayer exhibit cleavage fracture, intergranular fracture and mixed fracture composed of cleavage and tearing ridge, respectively. Compared with the brittle laves phase Fe2Ti, Ni3Ti phase can exhibit certain plasticity, block the crack propagation and change the direction of crack propagation. The composite structure of Ni3Ti and Fe2Ti will be formed when the FeNi alloy is taken as the interlayer, which provides the joint excellent mechanical properties, with rupture strength of 343 MPa.

    Figures and Tables | References | Related Articles | Metrics
    The growth mechanisms of θ′ precipitate phase in an Al-Cu alloy during aging treatment
    Lin Gao, Kai Li, Song Ni, Yong Du, Min Song
    J. Mater. Sci. Technol., 2021, 61 (0): 25-32.  DOI: 10.1016/j.jmst.2020.05.046
    Abstract   HTML   PDF

    The plate-shaped θ′ (Al2Cu) precipitate acts as one of the primary strengthening phases in Al-Cu alloys. The interface, especially the semicoherent interface, between Al-Cu solid solution (αAl) and θ′ phase contains a lot of clues about phase transformations. Thus, these interfacial structures in an Al-Cu alloy after high-temperature and longtime aging have been analyzed in detail using atomic-scale high-angle annular dark-field scanning transmission electron microscopy and first-principles calculations in this work. It was found that the lateral growth of θ' precipitates is subjected to a combination of several major mechanisms under this aging condition. Except for some common intermediate phases, two novel and striking structures were observed on the interface, which implies two alternative atomic diffusion mechanisms for θ′ precipitate growth. For one condition, the atomic diffusion from αAl to θ′ phase transformation adopts an interstitialcy mechanism based on additional Al atoms. For the other condition, the diffusion is carried out through Al atoms. Both mechanisms are distinctly different from the previous theory based on direct diffusion of Cu atoms. The first-principle calculations also confirm that these newfound diffusion processes are energetically favored.

    Figures and Tables | References | Related Articles | Metrics
    Antibacterial activities against Porphyromonas gingivalis and biological characteristics of copper-bearing PEO coatings on magnesium
    Dan Zhang, Qi Han, Kun Yu, Xiaopeng Lu, Ying Liu, Ze Lu, Qiang Wang
    J. Mater. Sci. Technol., 2021, 61 (0): 33-45.  DOI: 10.1016/j.jmst.2020.05.025
    Abstract   HTML   PDF

    Unlike other parts of the body, jaw defection often involves dental and periodontal tissues, which colonized a great many oral anaerobic bacteria. As a remarkable degradable material, magnesium has become an excellent candidate for orthopedic appliances recently. But the high degradation rate is still a big problem. Making a biodegradable coating with good biocompatibility to slow down the degeneration rate of magnesium is one of the best methods. However, protective coatings will impair the antibacterial effects of magnesium which is caused by the rise of pH value throughout its degradation. To solve this problem, a series of composite coatings with different amounts of CuO particles (3, 5 and 7 wt.%) were fabricated on pure magnesium through plasma electrolytic oxidation (PEO) to investigate in vitro biocompatibility and the antibacterial abilities against Porphyromonas gingivalis (P. gingivalis). Surface characterization and degradation behavior of the copper-bearing PEO coatings were also systematically studied. Furthermore, the most optimum coating was also systematically studied by X-ray photoelectron spectroscopy (XPS) and electrochemical corrosion test. Results of the present research revealed that adding proper amount of CuO into PEO coatings could greatly improve the antibacterial abilities of the PEO coatings. The antibacterial activities of copper-bearing PEO coatings were excellent and revealed concentration-dependent and time-dependent. Biocompatibility of copper-bearing PEO coatings showed that proper amount of Cu could promote cell proliferation. Compared with other PEO coatings in this study, PEO-7Cu showed some inhibition effects on cell proliferation and adhesion for long-term use. Electrochemical corrosion tests and immersion tests showed that PEO-5Cu and PEO-7Cu copper-bearing PEO coatings would provide satisfying corrosion resistance effects, while PEO-3Cu was poorer than PEO coatings without Cu. However, compared with uncoated pure magnesium, the corrosion resistance of the PEO coating was much better. Based on the results of antibacterial ability, biocompatibility, and corrosion resistance of the above copper-bearing PEO coatings, PEO-5Cu in this research was recommended to be used in patients with jaw defects.

    Figures and Tables | References | Related Articles | Metrics
    Invited Review
    Special issue on advanced corrosion-resistance materials and emerging applications. The progress on antifouling organic coating: From biocide to biomimetic surface
    Xu Han, Jianhua Wu, Xianhui Zhang, Junyou Shi, Jiaxin Wei, Yang Yang, Bo Wu, Yonghui Feng
    J. Mater. Sci. Technol., 2021, 61 (0): 46-62.  DOI: 10.1016/j.jmst.2020.07.002
    Abstract   HTML   PDF

    The advancement in material science and engineering technology has led to the development of antifouling (AF) coatings which are cheaper, durable, less toxic, and safe to the environment. The use of AF coatings containing tributyltin compounds was prohibited at the beginning of 2003, this necessitated the development of environmentally friendly coatings. The fouling release coating (FRC) lacks biocides and has low surface energy, low elastic modulus with smooth surface properties, hence a better release effect to fouling organisms. Several functional coatings have been recently developed based on fouling release (FR) technology to combat the effects of biofouling. Here, we provide a brief overview of innovative technologies and recent developments based on FRCs, including silicone, modified fluorinated polymer, cross-linked coatings, amphiphilic copolymer coating, hydrogel coatings, and biomimetic coatings. We also highlight the key issues and shortcomings of innovative technologies based on FRCs. This may give new insights into the future development of marine AF coatings.

    Figures and Tables | References | Related Articles | Metrics
    Research Article
    Contribution of ultrasonic surface rolling process to the fatigue properties of TB8 alloy with body-centered cubic structure
    Dan Liu, Daoxin Liu, Mario Guagliano, Xingchen Xu, Kaifa Fan, Sara Bagherifard
    J. Mater. Sci. Technol., 2021, 61 (0): 63-74.  DOI: 10.1016/j.jmst.2020.05.047
    Abstract   HTML   PDF

    The effect of ultrasonic surface rolling process (USRP) as a severe plastic deformation technology was investigated on the evolution of microstructure, residual stress and surface morphology of TB8 alloys with body-centered cubic structure. Stress-controlled rotating-bending fatigue tests indicated increased fatigue strength in USRP samples prepared using different number of passes compared to the base material, which was attributed to the presence of gradient structure surface layers. Five subsequent USRP passes resulted in the highest fatigue strength, due to the optimal surface properties including higher extent of grain refinement, larger compressive residual stresses, “smoother” surface morphology and increased micro-hardness. However, the effect of USRP technology on improving fatigue strength of TB8 alloy was not significant in comparison with that of other titanium alloys (for example, Ti6Al4V), which was attributed to the notable surface residual stresses relaxation revealed from measurements on post-fatigued USRP samples. Electron backscatter diffraction analysis confirmed that fatigue crack initiation occurred in the larger grains on the surface with high Schmid factor. Small cracks were found to propagate into the core material in a mixed transgranular and intergranular mode. Further analysis indicated that grain growth existed in post-fatigued USRP-treated TB8 samples and that the average geometrically necessary dislocations value reduced after fatigue loading.

    Figures and Tables | References | Related Articles | Metrics
    Balancing the corrosion resistance and through-plane electrical conductivity of Cr coating via oxygen plasma treatment
    Xian-Zong Wang, Hong-Qiang Fan, Triratna Muneshwar, Ken Cadien, Jing-Li Luo
    J. Mater. Sci. Technol., 2021, 61 (0): 75-84.  DOI: 10.1016/j.jmst.2020.06.012
    Abstract   HTML   PDF

    Developing an electrically conductive and corrosion-resistant coating is essential for metal bipolar plates of polymer electrolyte membrane fuel cells (PEMFCs). Although enhanced corrosion resistance was seen for Cr coated stainless steel (Cr/SS) bipolar plates, they experience a quick decrease of through-plane electrical conductivity due to the formation of a porous and low-conductive corrosion product layer at the plate surface, thus leading to an increase in interfacial contact resistance (ICR). To tackle this issue, the multilayer Cr coatings were deposited using the magnetron sputtering with a remote inductively coupled oxygen plasma (O-ICP) in the present study. After the O-ICP treatment, a Cr oxide layer (CrO*) is formed on the specimen surface. The CrO*/Cr/SS has a remarkably lower stable corrosion rate (iss) than that of the native Cr oxides (CrOn/Cr/SS). Compared with CrOn/Cr/SS, the excellent performance of CrO*/Cr/SS is attributed to a denser and thicker surface layer of CrO* with Cr being oxidized to its highest valence state, Cr (VI). More importantly, the through-plane electrical conductivity of the specimens treated by the optimized O-ICP decreases much slowly than CrOn/Cr/SS and thus, the increament of ICR of CrO*/Cr/SS after the potentiostatic polarization test is considerably smaller than that of CrOn/Cr/SS, which is benefited from the reduced iss that mitigates the deposition of corrosion products and hinders further oxidation of Cr coating. Therefore, CrO*/Cr/SS proves to be a well balanced trade-off between corrosion resistance and through-plane electrical conductivity. The results of this study demonstrate that O-ICP treatment on a conductive metal coating is an effective strategy to improve the corrosion resistance and suppress the increase of ICR over the long-term polarization. The technique reported herein exhibits its promising potential application in preparing corrosion resistant and electrically conductive coatings on metal bipolar plates to be used in PEMFCs.

    Figures and Tables | References | Related Articles | Metrics
    Namib desert beetle inspired special patterned fabric with programmable and gradient wettability for efficient fog harvesting
    Zhihua Yu, Huimei Zhang, Jianying Huang, Shuhui Li, Songnan Zhang, Yan Cheng, Jiajun Mao, Xiuli Dong, Shouwei Gao, Shanchi Wang, Zhong Chen, Yaoxing Jiang, Yuekun Lai
    J. Mater. Sci. Technol., 2021, 61 (0): 85-92.  DOI: 10.1016/j.jmst.2020.05.054
    Abstract   HTML   PDF

    Efficient collection of water from fog provides a potential solution to solve the global freshwater shortage problem, particularly in the desert or arid regions. In this work, a flexible and highly efficient fog collector was prepared by mimicking the back exoskeleton structure of the Namib desert beetle. The improved fog collector was constructed by a superhydrophobic-superhydrophilic patterned fabric via a simple weaving method, followed by in-situ deposition of copper particles. Compared with the conventional fog collector with a plane structure, the fabric has shown a higher water-harvesting rate at 1432.7 mg/h/cm2, owing to the biomimetic three-dimensional structure, its enhanced condensation performance enabled by the copper coating and the rational distribution of wetting units. The device construction makes use of the widely available textile materials through mature manufacturing technology, which makes it highly suitable for large-scale industrial production.

    Figures and Tables | References | Related Articles | Metrics
    Highly thermal-conductive graphite flake/Cu composites prepared by sintering intermittently electroplated core-shell powders
    Hong Sun, Nan Deng, Jianqiang Li, Gang He, Jiangtao Li
    J. Mater. Sci. Technol., 2021, 61 (0): 93-99.  DOI: 10.1016/j.jmst.2020.05.044
    Abstract   HTML   PDF

    Graphite flake/Cu composite has attracted tremendous attention as a promising heat sinks materials owing to its easy machinability and superior thermal properties. However, its preparation process still faces several technological limitations including complex, time-consuming and costly synthetic approaches. In this work, a facile and scalable intermittently electroplated method is applied to prepare Cu-coated graphite flake composite powders, which are subsequently sintered into dense composite bulks. The results show that the graphite flake is successfully coated with a uniform and compact Cu shell, which effectively inhibits the segregation accumulation of graphite flakes and contributes to homogeneous distribution of graphite in the sintered graphite flake/Cu composites. The as-sintered composites exhibit an excellent thermal conductivity of 710 W·m-1·K-1 and an outstanding bending strength of 93 MPa. Such performance, together with the simple, efficient powder-preparation process, suggests that the present strategy may open up opportunities for the development of thermal management materials.

    Figures and Tables | References | Related Articles | Metrics
    Optimizing the microstructures and mechanical properties of Al-Cu-based alloys with large solidification intervals by coupling travelling magnetic fields with sequential solidification
    Lei Luo, Liangshun Luo, Robert O. Ritchie, Yanqing Su, Binbin Wang, Liang Wang, Ruirun Chen, Jingjie Guo, Hengzhi Fu
    J. Mater. Sci. Technol., 2021, 61 (0): 100-113.  DOI: 10.1016/j.jmst.2020.05.048
    Abstract   HTML   PDF

    Alloys with large solidification intervals are prone to issues from the disordered growth and defect formation; accordingly, finding ways to effectively optimize the microstructure, further to improve the mechanical properties is of great importance. To this end, we couple travelling magnetic fields with sequential solidification to continuously regulate the mushy zones of Al-Cu-based alloys with large solidification intervals. Moreover, we combine experiments with simulations to comprehensively analyze the mechanisms on the optimization of microstructure and properties. Our results indicate that only downward travelling magnetic fields coupled with sequential solidification can obtain the refined and uniform microstructure, and promote the growth of matrix phase α-Al along the direction of temperature gradient. Additionally, the secondary dendrites and precipitates are reduced, while the solute partition coefficient and solute solid-solubility are raised. Ultimately, downward travelling magnetic fields can increase the ultimate tensile strength, yield strength, elongation and hardness from 196.2 MPa, 101.2 MPa, 14.5 % and 85.1 kg mm-2 without travelling magnetic fields to 224.1 MPa, 114.5 MPa, 17.1 % and 102.1 kg mm-2, and improve the ductility of alloys. However, upward travelling magnetic fields have the adverse effects on microstructural evolution, and lead to a reduction in the performance and ductility. Our findings demonstrate that long-range directional circular flows generated by travelling magnetic fields directionally alter the transformation and redistribution of solutes and temperature, which finally influences the solidification behavior and performance. Overall, our research present not only an innovative method to optimize the microstructures and mechanical properties for alloys with large solidification intervals, but also a detailed mechanism of travelling magnetic fields on this optimization during the sequential solidification.

    Figures and Tables | References | Related Articles | Metrics
    Interfacial dislocations dominated lateral growth of long-period stacking ordered phase in Mg alloys
    Qianqian Jin, Xiaohong Shao, Shijian Zheng, Yangtao Zhou, Bo Zhang, Xiuliang Ma
    J. Mater. Sci. Technol., 2021, 61 (0): 114-118.  DOI: 10.1016/j.jmst.2020.05.045
    Abstract   HTML   PDF

    Understanding the interface between strengthening precipitates and matrix in alloys, especially at the atomic level, is a critical issue for tailoring the precipitate strengthening to achieve desired mechanical properties. Using high-resolution scanning transmission electron microscopy, we here clarify the semi-coherent interfaces between the matrix and long-period stacking ordered (LPSO) phases, including 18R and 14H, in Mg-Zn-Y alloys. The LPSO/Mg interface features the unique configuration of the Shockley partial dislocations, which produces a near zero macroscopic strain because the net Burgers vectors equal zero. The 18R/Mg interface characterizes a dissociated structure that can be described as a narrow slab of 54R. There are two dislocation arrays accompanied to the 18R/54R and 54R/Mg interface, resulting a slight deviation (about 2.3°). The 14R/Mg interface exhibits the dislocation pairs associated with solute atoms. We further evaluate the stability and morphology of the corresponding interfaces based on elastic interaction, via calculating the mutual strong interactions between dislocation arrays, as well as that between the dislocations and solute atoms. The synchronized migration of interfacial dislocations and solute atoms, like move-drag behavior, dominates the lateral growth of LPSO phases in Mg alloys.

    Figures and Tables | References | Related Articles | Metrics
    Tensile deformation behavior and mechanical properties of a bulk cast Al0.9CoFeNi2 eutectic high-entropy alloy
    Hui Jiang, Dongxu Qiao, Wenna Jiao, Kaiming Han, Yiping Lu, Peter K. Liaw
    J. Mater. Sci. Technol., 2021, 61 (0): 119-124.  DOI: 10.1016/j.jmst.2020.05.053
    Abstract   HTML   PDF

    In this study, a new Al0.9CoFeNi2 eutectic high entropy alloy (EHEA) was designed, and the microstructures as well as the deformation behavior were investigated. The bulk cast Al0.9CoFeNi2 EHEA exhibited an order face-centered cubic FCC (L12) and an order body-centered cubic (B2) dual-phase lamellar eutectic microstructure. The volume fractions of FCC (L12) and B2 phases are measured to be 60 % and 40 %, respectively. The combination of the soft and ductile FCC (L12) phase together with the hard B2 phase resulted in superior strength of 1005 MPa and ductility as high as 6.2 % in tension at room temperature. The Al0.9CoFeNi2 EHEA exhibited obvious three-stage work hardening characteristics and high work-hardening ability. The evolving dislocation substructures during uniaxial tensile deformation found that planar slip dominates in both FCC (L12) and B2 phases, and the FCC (L12) phase is easier to deform than the B2 phase. The post-deformation transmission electron microscopy revealed that the sub-structural evolution of the FCC (L12) phase is from planar dislocations to bending dislocations, high-density dislocations, dislocation network, and then to dislocation walls, and Taylor lattices, while the sub-structural evolution of the B2 phase is from a very small number of short dislocations to a number of planar dislocations. Moreover, obvious ductile fracture in the FCC (L12) phase and a brittle-like fracture in the B2 phase were observed on the fracture surface of the Al0.9CoFeNi2 EHEA. The research results provide some insight into the microstructure-property relationship.

    Figures and Tables | References | Related Articles | Metrics
    Doped ceramics of indium oxides for negative permittivity materials in MHz-kHz frequency regions
    Guohua Fan, Zhongyang Wang, Kai Sun, Yao Liu, Runhua Fan
    J. Mater. Sci. Technol., 2021, 61 (0): 125-131.  DOI: 10.1016/j.jmst.2020.06.013
    Abstract   HTML   PDF

    Negative permittivity has been widely studied in various metamaterials and percolating composites, of which the anomalous dielectric behavior was attributed to critical structural properties of building blocks. Herein, mono-phase ceramics of indium tin oxides (ITO) were sintered for epsilon-negative materials in MHz-kHz frequency regions. Electrical conductivity and complex permittivity were analyzed with Drude-Lorentz oscillator model. Carriers’ characters were measured based on Hall effect and the magnitude and frequency dispersion of negative permittivity were mainly determined by carrier concentration. Temperature-dependent dielectric properties further proved the epsilon-negative behaviors were closely associated with free carriers’ collective responses. It’s found that negative permittivity of ITO ceramics was mainly caused by plasma oscillations of free carriers, while the dielectric loss was mainly attributed to conduction loss. Negative permittivity realized here was related to materials intrinsic nature and this work preliminarily determined the mechanism of negative permittivity in doped ceramics from the perspective of carriers.

    Figures and Tables | References | Related Articles | Metrics
    Nanocellulose-based reusable liquid metal printed electronics fabricated by evaporation-induced transfer printing
    Yiru Mao, Yixiang Wu, Pengju Zhang, Yang Yu, Zhizhu He, Qian Wang
    J. Mater. Sci. Technol., 2021, 61 (0): 132-137.  DOI: 10.1016/j.jmst.2020.05.040
    Abstract   HTML   PDF

    Reusable electronics have received widespread attention and are urgently needed. Here, nanocellulose-based liquid metal (NC-LM) printed circuit has been fabricated by the evaporation-induced transfer printing technology. In this way, the liquid metal pattern is embedded into the nanocellulose membrane, which is beneficial for the stability of the circuit during use. Besides, the NC-LM circuit is ultrathin with just tens of microns. In particular, the finished product is environmentally friendly because it can be completely dissolved by water, and both the liquid metal ink and the nanocellulose membrane can be easily recollected and reused, thereby reducing waste and pollution to the environment. Several examples of flexible circuits have been designed to evaluate their performance. The mechanism of evaporation-induced transfer printing technology involves the deposition, aggregation, and coverage tightly of the nanosized cellulose fibrils as the water evaporated. This study provides an economical and environmentally friendly way for the fabrication of renewable flexible electronics.

    Figures and Tables | References | Related Articles | Metrics
    Growth mechanism of primary Ti5Si3 phases in special brasses and their effect on wear resistance
    Xianlong Wang, Jinchuan Jie, Shichao Liu, Zhuangzhuang Dong, Guomao Yin, Tingju Li
    J. Mater. Sci. Technol., 2021, 61 (0): 138-146.  DOI: 10.1016/j.jmst.2020.05.063
    Abstract   HTML   PDF

    In the present work, in-situ Ti5Si3 reinforced special brasses were prepared by melt reaction method. The synthesized Ti5Si3 phase shows various morphologies in brasses with different Ti5Si3 content, and the 3D morphological evolution of primary Ti5Si3 and its growth mechanism were investigated. The Ti5Si3 crystal, which bears D88 hexagonal crystal structure, grows along <0001> direction and is revealed by {101$\bar{0}$} faces during growth. With the increase of Ti5Si3 content in the brasses, the morphology of primary Ti5Si3 significantly changes from fibers to hexagonal prisms to short-rods with hollow. In addition, the influence of Ti5Si3 volume fraction and morphology on the wear behavior of special brass was also revealed. It was substantiated that the wear resistance increases with the increasing volume fraction of Ti5Si3, and the corresponding wear mechanism changes from delamination to slight adhesive wear and abrasive wear. However, the friction coefficient shows an abnormal increase when most of the Ti5Si3 containing hollows appears in the brass. That is mainly due to the fact that the Ti5Si3 is easier to break and fall off resulted by the hollow as a crack source, which makes it unable to resist the plastic deformation of the contact surface during the sliding.

    Figures and Tables | References | Related Articles | Metrics
    Prediction of spatial distribution of the composition of inclusions on the entire cross section of a linepipe steel continuous casting slab
    Qiang Ren, Yuexin Zhang, Ying Ren, Lifeng Zhang, Jujin Wang, Yadong Wang
    J. Mater. Sci. Technol., 2021, 61 (0): 147-158.  DOI: 10.1016/j.jmst.2020.05.035
    Abstract   HTML   PDF

    In the current study, the transformation in the composition of non-metallic inclusions from the molten steel to the solidified steel was studied and the composition distribution of inclusions on the cross section of a linepine continuous casting slab was predicted. During cooling and solidification of the continuous casting strand, Al2O3-CaO inclusions reacted with the bulk steel and transformed to CaS-Al2O3-MgO-(CaO) ones in the continuous casting slab. The composition of inclusions on the cross section of the slab varied with locations due to the varied cooling rate. A model was established to predict the distribution of the composition of inclusions on the cross section of the continuous casting slab, coupling solidification and heat transfer of the continuous casting slab, the kinetic mass transfer of the dissolved elements in the solid steel, and thermodynamic calculation of inclusion transformation at different temperatures. The composition transformation of inclusions mainly occurred at the temperature between the liquidus and solidus of the linepipe steel. Inclusions were mainly CaS-Al2O3-MgO-(CaO) in slab center and were MgO-Al2O3-CaO-CaS within the subsurface of the slab. In the slab, the transformation fraction of inclusions was less than 10 % at corners while it reached 70 % at 50 mm below the surface of the slab.

    Figures and Tables | References | Related Articles | Metrics
    Efficient nanostructured heterogeneous catalysts by electrochemical etching of partially crystallized Fe-based metallic glass ribbons
    Qiaoyue Zhang, Shun-Xing Liang, Zhe Jia, Wenchang Zhang, Weimin Wang, Lai-Chang Zhang
    J. Mater. Sci. Technol., 2021, 61 (0): 159-168.  DOI: 10.1016/j.jmst.2020.06.016
    Abstract   HTML   PDF

    Although an increasing interest has been attracted to further develop heterostructured catalysts from metallic glasses (MGs) by heat treatment, overcoming surface oxidation effect is still a critical problem for such environmental catalysts. Herein, a short-time electrochemical etching of partially crystallized Fe-based ribbons in 0.3 M H3PO4 electrolyte enables the formation of honeycomb-like nanoporous structure as effective catalytic active sites in Fenton-like process. Studies of structure and surface morphologies reveal that the formation of nanoporous structure by potentiostatic etching originates from electrochemical potential difference of nanocrystals (α-Fe (Si) and Fe2B) and residual amorphous phase in partially crystallized ribbons, where Fe2B having a lower open circuit potential tends to be selectively dissolved. Simultaneously, thin oxide layer after electrochemical etching exposes more active sites for H2O2 activation and provides an effective protection of nanocrystals from massive loss during etching. Investigation of optimal processing conditions suggests that the selection of electrolyte plays an important role; dye degradation rates of etched ribbons in HNO3 and Na2SO4 electrolytes can also achieve at least 2 times higher than that of as-annealed ribbons. This work holds the promise to develop novel environmental catalysts by effective electrochemical etching of partially crystallized ribbons.

    Figures and Tables | References | Related Articles | Metrics
    Reversible grafting of antibiotics onto contact lens mediated by labile chemical bonds for smart prevention and treatment of corneal bacterial infections
    Bailiang Wang, Jiahong Zeng, Yishun Guo, Lin Liang, Yingying Jin, Siyuan Qian, Renjie Miao, Liang Hu, Fan Lu
    J. Mater. Sci. Technol., 2021, 61 (0): 169-175.  DOI: 10.1016/j.jmst.2020.05.062
    Abstract   HTML   PDF

    Eye trauma, decreased immunity, and contact lens wear often cause serious bacterial infections and irreversible corneal damage. To realize the responsive release of antibiotics such as gentamicin sulfate (GS), a novel antibacterial contact lens was constructed through self-assembly of antibiotics loaded ADA-GS/PEI (polyethyleneimine) multilayer films on the surface. Both in vitro and in vivo antibacterial tests demonstrated high efficient and fast antibacterial property based on the smart responsive to bacterial infections and reversible drug loading and release.

    Figures and Tables | References | Related Articles | Metrics
    Microstructure and mechanical properties in the TLP joint of FeCoNiTiAl and Inconel 718 alloys using BNi2 filler
    Lin Yuan, Jiangtao Xiong, Yajie Du, Jin Ren, Junmiao Shi, Jinglong Li
    J. Mater. Sci. Technol., 2021, 61 (0): 176-185.  DOI: 10.1016/j.jmst.2020.05.050
    Abstract   HTML   PDF

    High entropy alloy (HEA) of FeCoNiTiAl and Inconel 718 superalloy were firstly transient liquid phase (TLP) bonded by BNi2 filler due to the diffusion of Si and B in the filler to the base metals. The effects of bonding time on microstructure evolution and mechanical properties of the TLP joints were investigated. Owing to the complete isothermal solidification of the joints bonded for 30 min ~ 120 min at 1100 °C, no athermally solidified zones (ASZs) formed by eutectic phases were observed in the welded zone. Thus the TLP joints were only composed by the isothermally solidified zone (ISZ) and two diffusion affected zone (DAZ) adjacent to the dissimilar base metals and the negative effect of the ASZ on joint properties can be avoided. In addition, the increase of the bonding time can also make the TiB2 borides precipitated in the DAZ near HEA and the brittle borides or carbides in the DAZ near IN718 alloy decrease and reduce the possibility of the stress concentration happened in the joints under loading. Therefore, the highest shear strength (632.1 MPa) of the TLP joints was obtained at 1100 °C for 120 min, which was higher than that of the joint bonded for 30 min, 404.2 MPa. Furthermore, the extension of the bonding time made the fracture mechanism of the joint be transformed from the intergranular fracture to the transgranular fracture. However, as the brittle borides in the DAZ near IN718 can not be eliminated completely and refining of grains also happened in such region, all the TLP joints fractured inner the DAZ near IN718 alloy.

    Figures and Tables | References | Related Articles | Metrics
    Enhancing mechanical properties and corrosion resistance of nickel-aluminum bronze via hot rolling process
    Yanhua Zeng, Fenfen Yang, Zongning Chen, Enyu Guo, Minqiang Gao, Xuejian Wang, Huijun Kang, Tongmin Wang
    J. Mater. Sci. Technol., 2021, 61 (0): 186-196.  DOI: 10.1016/j.jmst.2020.05.024
    Abstract   HTML   PDF

    The mechanical properties and corrosion behavior of as-cast, as-annealed and hot-rolled nickel-aluminum bronze (NAB) alloy (Cu-9Al-10Ni-4Fe-1.2 Mn, all in wt.%) in 3.5 wt.% NaCl solution were investigated. The results show that annealing introduces a large number of κ phases to precipitate in the α phase. However, after further hot rolling, the original continuous κ phases are spheroidized and dispersed, increasing the strength, hardness, and elongation of the alloy. In addition to the enhanced mechanical properties, the corrosion resistance of the NAB samples is also improved significantly by hot rolling, as revealed by the mass loss measurements, electrochemical impedance spectroscopy (EIS), and cross-sectional corrosion morphology. Selective phase corrosion occurs by the preferential corrosion of the α phase, which acts as an anode to the κ phases, and the uncorroded κ phases are retained in the corrosion product film. The interfaces between the κ phases and the surrounding corrosion products become discontinuous caused by the spheroidization of κ phases, reducing the corrosion of the substrate by the corrosive medium via the channels. As a result, the corrosion rate and the maximum local corrosion depth of the hot-rolled NAB sample are greatly reduced.

    Figures and Tables | References | Related Articles | Metrics
    Coarsening kinetics and strengthening mechanisms of core-shell nanoscale precipitates in Al-Li-Yb-Er-Sc-Zr alloy
    Yang Wang, Shun Zhang, Ruizhi Wu, Nodir Turakhodjaev, Legan Hou, Jinghuai Zhang, Sergey Betsofen
    J. Mater. Sci. Technol., 2021, 61 (0): 197-203.  DOI: 10.1016/j.jmst.2020.05.061
    Abstract   HTML   PDF

    The tailored nanoparticles with a complex core/shell structure can satisfy a variety of demands, such as lattice misfit, shearability and coarsening resistance. In this research, core-shell nanoscale Al3(Yb, Er, Sc, Zr, Li) composite particles were precipitated in Al-2Li-0.1Yb-0.1Er-0.1Sc-0.1 Zr (wt%) alloy through the double-aging treatment, in which the core was (Yb, Er, Sc, Zr)-rich formed at 300 °C and the shell was Li-rich formed at 150 °C. The coarsening kinetics and precipitate size distributions (PSDs) of Al3(Yb, Er, Sc, Zr, Li) particles aged at 150 °C previously aged at 300 °C for 24 h showed a better fit to the relation of <r>2kt and normal distribution, indicating that the coarsening of precipitates was controlled by interface reaction, not diffusion. The Orowan bypass strengthening was operative mechanism at 150 °C.

    Figures and Tables | References | Related Articles | Metrics
    Critical transitions in the shape morphing of kirigami metallic glass
    D.X. Han, L. Zhao, S.H. Chen, G. Wang, K.C. Chan
    J. Mater. Sci. Technol., 2021, 61 (0): 204-212.  DOI: 10.1016/j.jmst.2020.05.065
    Abstract   HTML   PDF

    Kirigami, the ancient Japanese paper cutting technique, has been applied to achieve high stretchability and low energy loss of designed metallic glass. Despite the exploration of the underlying deformation mechanism of kirigami-inspired structures from the energy point of view, the morphable responses of the kirigami patterns and the origin of the kirigami response are yet to be fully understood. This study reveals the mechanical driven-forms of the kirigami structure with the corresponding deformation stages. Based on the beam deflection theory, the elastic buckling behavior of kirigami metallic glass is manifested and a critical force prediction model is developed. Moreover, a force concentration parameter is introduced in the rigid-plastic deformation stage, predicting the nominal ultimate force. The kirigami-inspired facture force is firstly proposed. The findings of these models are in good agreement with the experimental size-dependent kirigami responses, and expected to provide significant insights into the understanding of the deformation behavior and the design of kirigami metallic glasses.

    Figures and Tables | References | Related Articles | Metrics
    Letter
    Preparation of hysteresis-free flexible perovskite solar cells via interfacial modification
    Xiaofang Ye, Hongkun Cai, Jian Su, Jingtao Yang, Jian Ni, Juan Li, Jianjun Zhang
    J. Mater. Sci. Technol., 2021, 61 (0): 213-220.  DOI: 10.1016/j.jmst.2020.05.029
    Abstract   HTML   PDF

    In recent years, flexible perovskite solar cells have received extensive attention and rapid development due to their advantages of lightweight, portability, wearability and applications in near-space. However, due to the limitations of their preparation process and other factors, high-efficiency and large-area flexible perovskite solar cells still have a lot of room for development. In our work, a flexible perovskite solar cell (PEN/ITO/SnO2/KCl/Cs0.05 (MA0.17FA0.83)0.95Pb(I0.83Br0.17)3/spiro/Au) was prepared using a low temperature (no higher than 100 °C) solution process, and the device with the highest efficiency of 16.16% was obtained by adjusting the concentration of the KCl modified layer. Meanwhile, the efficiency of the large area (1 cm2) flexible solar cell was higher than 13%. At the same time, the passivation of the KCl interface modification layer inhibits the formation of the defect states, which reduced the surface recombination of the perovskite and improved the carrier transport performance, and the hysteresis effect of the device was also reduced accordingly.

    Figures and Tables | References | Related Articles | Metrics
    Research Article
    Microstructural homogeneity and mechanical behavior of a selective laser melted Ti-35Nb alloy produced from an elemental powder mixture
    Jincheng Wang, Yujing Liu, Chirag Dhirajlal Rabadia, Shun-Xing Liang, Timothy Barry Sercombe, Lai-Chang Zhang
    J. Mater. Sci. Technol., 2021, 61 (0): 221-233.  DOI: 10.1016/j.jmst.2020.05.052
    Abstract   HTML   PDF

    Although using elemental powder mixtures may provide broad alloy selection at low cost for selective laser melting (SLM), there is still a concern on the resultant microstructural and chemical homogeneity of the produced parts. Hence, this work investigates the microstructure and mechanical properties of a SLM-produced Ti-35Nb composite (in wt%) using elemental powder. The microstructural characteristics including β phase, undissolved Nb particles and chemical homogeneity were detailed investigated. Nanoindentation revealed the presence of relatively soft undissolved Nb particles and weak interface bonding around Nb-rich regions in as-SLMed samples. Solid-solution treatment can not only improve chemical homogeneity but also enhance bonding through grain boundary strengthening, resulting in ~43 % increase in tensile elongation for the heat-treated Ti-35Nb compared to the as-SLMed counterpart. The analyses of tensile fractures and shear bands further confirmed the correlation between the different phases and the ductility of Ti-35Nb. In particular, the weak bonding between undissolved Nb and the matrix in the as-SLMed sample reduces its ductility while the β grains in solid-solution treated Ti-Nb alloy can induce a relatively stable plastic flow therefore better ductility. This work sheds insight into the understanding of homogenization of microstructure and phases of SLM-produced alloys from an elemental powder mixture.

    Figures and Tables | References | Related Articles | Metrics
    Influence of cementite spheroidization on relieving the micro-galvanic effect of ferrite-pearlite steel in acidic chloride environment
    Hu Liu, Jie Wei, Junhua Dong, Yiqing Chen, Yumin Wu, Yangtao Zhou, Subedi Dhruba Babu, Wei Ke
    J. Mater. Sci. Technol., 2021, 61 (0): 234-246.  DOI: 10.1016/j.jmst.2020.05.031
    Abstract   HTML   PDF

    The corrosion behavior of the as-received steel and the spheroidized steel in acidic chloride environment was investigated. The results indicate the corrosion mode and corrosion rate of two steels are diverse due to their difference in microstructure. For as-received steel with ferrite-pearlite microstructure, severe localized corrosion happens on the pearlite regions, and plenty of cathodic cementite remains in the pits, further strengthening the micro-galvanic effect and accelerating the corrosion rate. While for spheroidized steel with tempered martensite microstructure, the nanosized cementite particles evenly distributed on the ferrite substrate are easy to fall off, which can significantly reduce the cementite accumulation on the steel surface, relieving the acceleration effect of micro-galvanic corrosion.

    Figures and Tables | References | Related Articles | Metrics
ISSN: 1005-0302
CN: 21-1315/TG
Home
About JMST
Privacy Statement
Terms & Conditions
Editorial Office: Journal of Materials Science & Technology , 72 Wenhua Rd.,
Shenyang 110016, China
Tel: +86-24-83978208
E-mail:JMST@imr.ac.cn

Copyright © 2016 JMST, All Rights Reserved.