检索结果-南通市图书馆

Synergistic effect of gradient Zn content and multiscale particles on the mechanical properties of Al-Zn-Mg-Cu alloys with coupling distribution of coarse-fine grains

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and materials 2024年第6期31卷 1392-1405页

作者： Liangliang Yuan Mingxing Guo Yi Wang Yun Wang Linzhong Zhuang Institute of Effectiveness Evaluation of Flying Vehicle Beijing 100085China State key laboratory for advanced Metals and materials University of Science and Technology BeijingBeijing 100083China Beijing advanced Innovation Center for materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing laboratory of metallic materials and processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China

This study investigated the influence of graded Zn content on the evolution of precipitated and iron-rich phases and grain struc-ture of the alloys,designed and developed the Al–8.0Zn–1.5Mg–1.5Cu–0.2Fe(wt%)alloy with high strength and formability.With the increase of Zn content,forming the coupling distribution of multiscale precipitates and iron-rich phases with a reasonable matching ratio and dispersion distribution characteristics is easy.This phenomenon induces the formation of cell-like structures with alternate distribu-tion of coarse and fine grains,and the average plasticity–strain ratio(characterizing the formability)of the pre-aged alloy with a high strength is up to 0.708.Results reveal the evolution and influence mechanisms of multiscale second-phase particles and the corresponding high formability mechanism of the alloys.The developed coupling control process exhibits considerable potential,revealing remarkable improvements in the room temperature formability of high-strength Al–Zn–Mg–Cu alloys.

关键词： Al–Zn–Mg–Cu alloy iron-rich phase high formability microstructure mechanisms

Microstructure recognition of steels by machine learning based on visual attention mechanism

在线全文

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research(International) 2024年第4期31卷 909-923页

作者： Xing-yu Chen Lin Cheng Cheng-yang Hu Yu-peng Zhang Kai-ming Wu The State key laboratory of Refractories and Metallurgy Hubei Province Key Laboratory of Systems Science on Metallurgical ProcessingInternational Research Institute for Steel TechnologyCollaborative Center on Advanced SteelsWuhan University of Science and TechnologyWuhan 430081HubeiChina Metals Valley and Band(Foshan)metallic Composite materials Co. Ltd.Foshan 528000GuangdongChina

U-Net has achieved good performance with the small-scale datasets through skip connections to merge the features of the low-level layers and high-level layers and has been widely utilized in biomedical image segmentation as well as recent microstructure image segregation of the materials.Three representative visual attention mechanism modules,named as squeeze-and-excitation networks,convolutional block attention module,and extended calibration algorithm,were intro-duced into the traditional U-Net architecture to further improve the prediction accuracy.It is found that compared with the original U-Net architecture,the evaluation index of the improved U-Net architecture has been significantly improved for the microstructure segmentation of the steels with the ferrite/martensite composite microstructure and pearlite/ferrite composite microstructure and the complex martensite/austenite island/bainite microstructure,which demonstrates the advantages of the utilization of the visual attention mechanism in the microstructure segregation.The reasons for the accuracy improvement were discussed based on the feature maps analysis.

关键词： Microstructure recognition-Steel Machine learning Visual attention mechanism Visualization

Microstructure and forming mechanism of metals subjected to ultrasonic vibration plastic forming: A mini review

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and materials 2024年第6期31卷 1322-1332页

作者： Qinghe Cui Xuefeng Liu Wenjing Wang Shaojie Tian Vasili Rubanik Vasili Rubanik Jr. Dzmitry Bahrets Beijing advanced Innovation Center for materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Beijing laboratory of metallic materials and processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Institute for advanced materials and Technology University of Science and Technology BeijingBeijing 100083China Institute of Technical Acoustics National Academy of SciencesVitebsk 210009Belarus

Compared with traditional plastic forming,ultrasonic vibration plastic forming has the advantages of reducing the forming force and improving the surface quality of the workpiece.This technology has a very broad application prospect in industrial manufactur-ing.Researchers have conducted extensive research on the ultrasonic vibration plastic forming of metals and laid a deep foundation for the development of this field.In this review,metals were classified according to their crystal structures.The effects of ultrasonic vibration on the microstructure of face-centered cubic,body-centered cubic,and hexagonal close-packed metals during plastic forming and the mech-anism underlying ultrasonic vibration forming were reviewed.The main challenges and future research direction of the ultrasonic vibra-tion plastic forming of metals were also discussed.

关键词： ultrasonic vibration plastic forming crystal structure microstructure forming mechanism

Isotropic sintering shrinkage of 3D glass-ceramic nanolattices:backbone preforming and mechanical enhancement

在线全文

学校读者我要写书评

暂无评论

International Journal of Extreme Manufacturing 2024年第2期6卷 418-426页

作者： Nianyao Chai Yunfan Yue Xiangyu Chen Zhongle Zeng Sheng Li Xuewen Wang Center of Femtosecond Laser Manufacturing for advanced materials and Devices State Key Laboratory of Advanced Technology for Materials Synthesis and ProcessingWuhan University of TechnologyWuhan 430070People’s Republic of China National Energy key laboratory for New Hydrogen-Ammonia Energy Technologies Foshan Xianhu LaboratoryFoshan 528000People’s Republic of China International School of materials Science and Engineering Wuhan University of TechnologyWuhan 430070People’s Republic of China

There is a perpetual pursuit for free-form glasses and ceramics featuring outstanding mechanical properties as well as chemical and thermal resistance.It is a promising idea to shape inorganic materials in three-dimensional(3D)forms to reduce their weight while maintaining high mechanical properties.A popular strategy for the preparation of 3D inorganic materials is to mold the organic–inorganic hybrid photoresists into 3D micro-and nano-structures and remove the organic components by subsequent sintering.However,due to the discrete arrangement of inorganic components in the organic-inorganic hybrid photoresists,it remains a huge challenge to attain isotropic shrinkage during sintering.Herein,we demonstrate the isotropic sintering shrinkage by forming the consecutive–Si–O–Si–O–Zr–O–inorganic backbone in photoresists and fabricating 3D glass–ceramic nanolattices with enhanced mechanical properties.The femtosecond(fs)laser is used in two-photon polymerization(TPP)to fabricate 3D green body structures.After subsequent sintering at 1000℃,high-quality 3D glass–ceramic microstructures can be obtained with perfectly intact and smooth morphology.In-suit compression experiments and finite-element simulations reveal that octahedral-truss(oct-truss)lattices possess remarkable adeptness in bearing stress concentration and maintain the structural integrity to resist rod bending,indicating that this structure is a candidate for preparing lightweight and high stiffness glass–ceramic nanolattices.3D printing of such glasses and ceramics has significant implications in a number of industrial applications,including metamaterials,microelectromechanical systems,photonic crystals,and damage-tolerant lightweight materials.

关键词： 3D printing isotropic shrinkage femtosecond laser two-photon polymerization structural glass-ceramics

Unveiling the time-temperature dependence of metastability of supercooled liquid using nano-calorimetry

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 119-127页

作者： Yijun Ding Lijian Song Zheng Wang Ruiqi Yu Junqiang Wang Lina Hu Yuanzheng Yue Edgar D.Zanotto key laboratory for Liquid-Solid Structural Evolution and processing of materials(Ministry of Education) Shandong University Jinan 250061China Ningbo Institute of materials Technology and Engineering Chinese Academy of SciencesNingbo 315201China key laboratory of Experimental Teratology Shandong University Jinan 250061 China Department of Chemistry and Bioscience Aalborg UniversityAalborg 9220Denmark Department of materials Engineering Federal University of Sao CarlosSao Carlos SP 13.565-905Brazil

There is a lack of understanding of both the conversion of an unstable glass into a metastable supercooled liquid(MSL) upon heating and the metastability of MSLs. In this study, we investigated the time-and temperature-dependent metastability of an MSL using an advanced nano-calorimetric technique. The chosen Au-based metallic glass(Au MG) allowed adequate probing of its MSL in a temperature range between 10 and 70 K above the standard glass transition temperature. We found that the survival time of the MSL state is a quadratic function of temperature. Beyond this duration threshold, the sample undergoes fast crystallization even if it is below the crystallization temperature that is measured using differential scanning calorimetry.Employing transmission electron microscopy, we observed the formation of clusters with a partially ordered lattice structure during relaxation in the Au MG sample fabricated using a nano-calorimeter. The atomic ordering within the clusters was enhanced by increasing time and temperature in the MSL region. Once the as-produced glass entered the MSL stage upon heating followed by a quenching stage at a given rate, the mechanical properties of the quenched glass remained the same regardless of its holding temperature and duration within the MSL region. This work provides insights into the glass-MSL-crystal transformation and offers guidance for designing standard metallic glasses for property characterizations.

关键词： metallic glass supercooled liquid relaxation nucleation nano calorimetric technology

High-tenacity in-situ Ti/Zr-based bulk metallic glasses composites fabricated by industrial high-pressure die casting

在线全文

学校读者我要写书评

暂无评论

Journal of materials Science & Technology 2024年第3期170卷 177-185页

作者： Yang Li Wenbo Luo Ying Jin Zhiyong Xue Guiqing Wang Yanan Ren Haoxin Li Haibo Ke Baoan Sun Weihua Wang Institute for advanced materials North China Electric Power UniversityBeijing 102206China Songshan Lake materials laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China

The glass-forming ability and mechanical properties of metallic glasses and their composites are well known to be sensitive to the preparation conditions and are highly deteriorated by industrial preparing conditions such as low-purity raw materials and low vacuum.Here,we showed that a series of in-situ bulk metallic glass composites(BMGCs)which exhibit excellent ductility and segmental work hardening were successfully developed utilizing a high vacuum high-pressure die casting(HV-HPDC)technology along with industrial-grade raw materials.The tensile properties of these BMGCs are systematically investigated and correlated with the alloy microstructure.As compared with the copper mold suction casting method,the volume fraction difference of the dendrite phase for the BMGCs with the same composition is not significant when fabricated by the HV-HPDC,whereas the size of theβ-phase is generally larger.Insitu BMGCs with the composition of Ti_(48)Zr_(20)(V_(12/17)Cu_(5/17))19 Be 13 obtained by the HV-HPDC process show ductility up to 11.3%under tension at room temperature and exhibit a certain amount of work hardening.Two conditions need to be met to enable the BMGCs,which are prepared by vacuum die-casting to retain favorable ductility:(1)The volume fraction ofβphase stays below 62%±2%;(2)The equiaxed crystals with a more uniform size in the range of 5-10μm.Meanwhile,the results of the present study provided guidance for developing BMGCs with good ductile properties under industrial conditions.

关键词： Vacuum die casting Bulk metallic glass composites Mechanical properties β-phase

Functional dissection of parabrachial substrates in processing nociceptive information

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Zoological Research 2024年第3期45卷 633-647页

作者： Jin Ke Wei-Cheng Lu Hai-Yang Jing Shen Qian Sun-Wook Moon Guang-Fu Cui Wei-Xin Qian Xiao-Jing Che Qian Zhang Shi-Shi Lai Ling Zhang Ying-Jie Zhu Jing-Dun Xie Tian-Wen Huang Shenzhen key laboratory of Drug Addiction Shenzhen-Hong Kong Institute of Brain ScienceBrain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China CAS key laboratory of Brain Connectome and Manipulation Brain Cognition and Brain Disease InstituteShenzhen Institute of Advanced TechnologyChinese Academy of SciencesShenzhenGuangdong 518055China University of Chinese Academy of Sciences Beijing 100049China Department of Anesthesiology State Key Laboratory of Oncology in South ChinaGuangdong Provincial Clinical Research Center for CancerSun Yat-sen University Cancer CenterGuangzhouGuangdong 510060China University of Science and Technology of China HefeiAnhui 230027China Department of Anesthesiology Shenzhen University General Hospital and Shenzhen University Academy of Clinical Medical SciencesShenzhen UniversityShenzhenGuangdong 518055China School of Medicine Yunnan UniversityKunmingYunnan 650091China

Painful stimuli elicit first-line reflexive defensive reactions and,in many cases,also evoke second-line recuperative behaviors,the latter of which reflects the sensing of tissue damage and the alleviation of suffering.The lateral parabrachial nucleus(lPBN),composed of external-(elPBN),dorsal-(dlPBN),and central/superior-subnuclei(jointly referred to as slPBN),receives sensory inputs from spinal projection neurons and plays important roles in processing affective information from external threats and body integrity disruption.However,the organizational rules of lPBN neurons that provoke diverse behaviors in response to different painful stimuli from cutaneous and deep tissues remain unclear.In this study,we used region-specific neuronal depletion or silencing approaches combined with a battery of behavioral assays to show that slPBN neurons expressing substance P receptor(NK1R)(lPBNNK1R)are crucial for driving pain-associated self-care behaviors evoked by sustained noxious thermal and mechanical stimuli applied to skin or bone/muscle,while elPBN neurons are dispensable for driving such reactions.Notably,lPBNNK1R neurons are specifically required for forming sustained somatic pain-induced negative teaching signals and aversive memory but are not necessary for fear-learning or escape behaviors elicited by external threats.Lastly,both lPBNNK1R and elPBN neurons contribute to chemical irritant-induced nocifensive reactions.Our results reveal the functional organization of parabrachial substrates that drive distinct behavioral outcomes in response to sustained pain versus external danger under physiological conditions.

关键词： Lateral parabrachial nucleus Substance P receptor Pain affect Defensive reaction Somatosensory

Microstructural evolution and superelastic properties of ultrafine-graine d NiTi-base d shape memory alloy via sintering of amorphous ribbon precursor

同方期刊数据库博看期刊评论

在线全文

学校读者我要写书评

暂无评论

Journal of materials Science & Technology 2023年第7期138卷 80-92页

作者： W.S.Cai H.Z.Lu H.Z.Li Z.Liu H.B.Ke W.H.Wang C.Yang National Engineering Research Center of Near-net-shape forming for metallic materials Guangdong Provincial Key Laboratory for Processing and Forming of Advanced Metallic MaterialsSouth China University of TechnologyGuangzhou 510640China Songshan Lake materials laboratory Dongguan 523808China Institute of Physics Chinese Academy of SciencesBeijing 100190China

NiTi-based shape memory alloys(SMAs)are considered as cutting-edge intelligent functional materials.However,it remains a great challenge to obtain ultrafine-grained(UFGed)bulk materials with mm-scale size as well as outstanding superelastic properties.Here,UFGed bulk Ti_(35)Zr_(15)Ni_(35)Cu_(15)NiTi-based SMA is successfully prepared via spark plasma sintering of amorphous ribbon precursor at different sintering temperatures,and microstructural evolution and superelastic properties are symmetrically investigated.It is found that its grain size ranges from UFG to micro-grain with increased sintering temperature regard-less of the predominant B2 matrix in all bulk samples.Interestingly,the orientation relationships between B2 matrix and nano-scale fcc(Ti,Zr)_(2)Ni precipitate evolve from coherent to incoherent.Consequently,the UFGed samples exhibit perfect superelasticity with the high recoverable strain of∼5.8%,the stable recov-ery rate above 99%,and the great critical stress inducing martensitic transformation higher than 1 GPa,far superior to the corresponding ones of suction-cast micro-grained TiZrNiCu SMAs.Fundamentally,the perfect superelasticity is attributed to the good resistance to dislocation slip or grain boundary slip by residual nano-scale amorphous phase or secondary phase of coherent and semi-coherent fcc(Ti,Zr)_(2)Ni precipitate.In addition,the gentle superelastic plateau is associated to the favorable transfer stress and the strong ability to accommodate dislocation movement,which is generated by the coherent interface between nano-scale fcc(Ti,Zr)_(2)Ni and UFGed B2 matrix.These results suggest that spark plasma sintering of amorphous alloy precursor is a feasible route to obtaining excellent superelasticity in NiTi-based SMAs.

关键词： Shape memory alloy Amorphous alloy Microstructure Superelasticity

An Al–Al interpenetrating-phase composite by 3D printing and hot extrusion

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

International Journal of Minerals,Metallurgy and materials 2023年第4期30卷 678-688页

作者： Yulin Lin Di Wang Chao Yang Weiwen Zhang Zhi Wang School of Mechanical and Automotive Engineering South China University of TechnologyGuangzhou 510640China guangdong key laboratory for processing and forming of advanced metallic materials South China University of TechnologyGuangzhou 510640China

We report a process route to fabricate an Al–Al interpenetrating-phase composite by combining the Al–Mg–Mn–Sc–Zr lattice structure and Al_(84)Ni_(7)Gd_(6)Co_(3)nanostructured structure. The lattice structure was produced by the selective laser melting and subsequently filled with the Al_(84)Ni_(7)Gd_(6)Co_(3)amorphous powder, and finally the mixture was used for hot extrusion to produce bulk samples. The results show that the composites achieve a high densification and good interface bonding due to the element diffusion and plastic deformation during hot extrusion.The bulk samples show a heterogeneous structure with a combination of honeycomb lattice structure with an average grain size of less than1 μm and nanostructured area with a high volume fraction of nanometric intermetallics and nanograin α-Al. The heterogeneous structure leads to a bimodal mechanical zone with hard area and soft area giving rise to high strength and acceptable plasticity, where the compressive yield strength and the compressive plasticity can reach ~745 MPa and ~30%, respectively. The high strength can be explained by the rule of mixture,the grain boundary strengthening, and the back stress, while the acceptable plasticity is mainly owing to the confinement effect of the nanostructured area retarding the brittle fracture behavior.

关键词： Al-based composites heterogeneous structure additive manufacturing mechanical properties