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High-Speed Rubbing Behavior of Abrasive Coating Coated on Titanium Alloy Blade Tips

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 749-762页

作者： Wenshuang Gu Shuai Yang Shiyi Zhang Zhiliang Pei Weihai Xue Deli Duan Jun Gong Chao Sun Shi-Changxu Innovation center for Advanced materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China School of materials Science and Engineering University of Science and Technology of ChinaShenyang110016China

In aero-engines, abrasive coatings are typically utilized to protect the blade tip from excessive wear caused by the harder abradable sealing coating and thereby improve the sealing performance of engines. Therefore, a Ni/cBN abrasive coating was prepared on titanium alloy using electrodeposition. The high-speed rubbing tests with a linear velocity of 350 m/s and different incursion rates were performed to investigate the effect of the Ni/cBN abrasive coating on the wear behavior against NiCrAl/diatomite seal coating. Results showed that melting wear and adhesive transfer occurred on the bare blades, causing the bare blade to suffer excessive wear. While the Ni/cBN abrasive coating exhibited superior wear resistance and cutting performance. The cBN grits pullout, the abrasion of Ni matrix and transfer of seal coating to the cBN grits were the main wear mechanism of the Ni/cBN abrasive coating. Additionally, it was found that the relationship between the incursion rate and high-speed rubbing behavior is quite different for the bare blade and Ni/cBN coating. The reason for the difference in wear behavior of bare blade and Ni/cBN coating at different incursion rates was discussed in detail.

关键词： Gas turbine sealing Abrasive coating High-speed rubbing Material transfer Abradable coating

Stable ultraviolet ultrafast laser based on all-polarizationmaintaining fiber femtosecond laser

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Chinese Optics Letters 2024年第3期22卷 76-82页

作者：田昊朱喆林巍李子豪温俊鹏修昊范怡衡韦池一韦小明杨中民 School of Physics and Optoelectronics/State Key Laboratory of Luminescent materials and Devices Guangdong Engineering Technology Research and Development Center of Special Optical Fiber Materials and DevicesGuangdong Provincial Key Laboratory of Fiber Laser Materials and Applied TechniquesSouth China University of TechnologyGuangzhou 510640China research Institute of Future Technology South China Normal UniversityGuangzhou 510006China

We report a high-stability ultrafast ultraviolet(UV)laser source at 352 nm by exploring an all-fiber,all-polarizationmaintaining(all-PM),Yb-doped femtosecond fiber laser at 1060 *** output power,pulse width,and optical spectrum width of the fiber laser are 6 W,244 fs,and 17.5 nm,*** UV ultrashort pulses at a repetition rate of 28.9 MHz are generated by leveraging single-pass second-harmonic generation in a 1.3-mm-long BiB_(3)O_(6)(BIBO)and sum frequency generation in a 5.1-mm-long *** maximum UV output power is 596 *** root mean square error of the output power of UV pulses is 0.54%.This laser,with promising stability,is expected to be a nice source for frontier applications in the UV wavelength window.

关键词： all-polarization-maintaining fiber ultrafast fiber laser UV laser

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Microstructural Evolutions and Mechanical Properties of Energetic Al_(1) (TiZrNbTaMoCr)_(15) High-Entropy Alloys

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Acta Metallurgica Sinica(English Letters) 2024年第4期37卷 620-632页

作者： Xuan-Hong Cai Zhen-Hua Wang Ben Niu Jin-Feng Li Qing Wang Show authors Key Laboratory of materials Modification By Laser Ion and Electron Beams(Ministry of Education)Engineering Research Center of High Entropy Alloy Materials(Liaoning Province)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Institute of materials China Academy of Engineering PhysicsMianyang621908China

The present study focuses on investigating the microstructural evolutions and mechanical properties of energetic Al_(1)(TiZrNbTaMoCr)_(15) refractory high-entropy alloys with the different heat treatments at low Al content state. It is found that even with a reduction in the Al content, the strength of these alloys remains unaffected at room temperature and high temperature, while the plasticity improves significantly. In particular, the coherent BCC/B_(2) microstructure with needle-like B_(2) nanoprecipitates dispersed into the BCC matrix is formed in 873 K-aged Al_(1)Ti_(6)Zr_(2)Nb_(3)Ta_(3)Mo_(0.5)Cr_(0.5) alloy. Therefore, this alloy exhibits the highest compression yield strength (σ_(YS) = 1333 and 717 MPa) at room temperature and 1073 K, respectively. After 973 K-aged, the coherent BCC/B_(2) microstructure underwent destabilization, and the B_(2) phase transforms into the brittle Zr5Al3 phase which then coarsens and dominates the microstructure of S3-AlTa_(3) alloy after 1073 K-aged. Moreover, these current alloys exhibit exceptionally high theoretical exothermic enthalpy (ΔH), surpassing 11606 J·g^(−1), which highlights their significant potential as innovative high-performance energetic structural materials.

关键词： Refractory high-entropy alloy Coherent microstructure Mechanical property Exothermic enthalpy

Strong and tough chitin hydrogel constructed by dehydration and rehydration strategy

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Nano research 2024年第9期17卷 8192-8199页

作者： Rui-Rui Liu Li-Bo Mao Shu-Hong Yu Division of Nanomaterials and Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials and ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China Institute of Innovative materials Department of Materials Science and EngineeringDepartment of ChemistrySouthern University of Science and TechnologyShenzhen 518055China

As a renewable,biocompatible,biodegradable soft material,chitin hydrogels have better advantages in stability,antibacterial activity,antifouling,cost,immunogenicity,and so on than most polymer ***,compared with other widely used polymer hydrogels with high strength and toughness,the practical applications of chitin-based hydrogels have been limited by their weak mechanical properties,such as cartilage repair and meniscus ***,we present the design and fabrication of chitin hydrogels with excellent mechanical strength and toughness by a dehydration and rehydration *** sequential dehydration and rehydration processes,the crystalline domains in the chitin hydrogels can be properly *** optimized crystallinity,the elastic modulus of the chitin hydrogels exceeds all previously reported values,and the fracture toughness is even comparable to some synthetic polymer hydrogels,while maintaining a high-water-content of about 80 wt.%.At the same water content,the mechanical properties of the chitin hydrogels are positively correlated with the hydrogel crystallinity,which proves that the change of mechanical properties of hydrogels is not simply dependent on weight *** hydrogels can be further strengthened by incorporating other biopolymers that are intrinsically weak,which makes the hydrogels promising for applications in fields such as cartilage repair and meniscus ***,the hydrogels enable loading and release of water-soluble and poorly water-soluble *** highly extendable strengthening and toughening strategy of chitin and chitin-based biopolymer hydrogels paves the way for their widely applications.

关键词： chitin hydrogel crystallinity rehydration chemical transformation strong and tough

Boosting propane dehydrogenation of defective S-1 stabilized singleatom Pt and ZnO catalysts via coordination environment regulation

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Nano research 2024年第7期17卷 5884-5896页

作者： Fuwen Yang Jie Zhang Jinwei Chen Gang Wang Tong Yu Qian Li Zongbo Shi Qiushi Sun Runsheng Zhuo Ruilin Wang College of materials Science and Engineering Sichuan UniversityChengdu 610065China Engineering research center of Alternative Energy materials&Devices Ministry of EducationSichuan UniversityChengdu 610065China REZEL Catalysts Corporation Shanghai 200120China

Pt single atoms catalysts with precise coordination environment and high stability are expected to achieve high performance of propane dehydrogenation(PDH).In this work,an innovative synthetic strategy is proposed to construct the S-1@0.1Pt9Zn@DPS-1 nanocomposite as a highly efficient PDH *** engineering is applied to induce the formation of defective porous silicalite-1(DPS-1),which is favorable for achieving the uniformly distributed ZnO *** ZnO nanoclusters were further served as anchoring sites to stabilize the isolated Pt *** structural characterization revealed that penta-O coordinated Pt single atom coupled with ZnO nanoclusters decorated on the ***,the atomically dispersed Pt atoms with the ideal coordination environment could act as the predominant active sites for PDH *** expected,the optimal S-1@0.1Pt9Zn@DPS-1 catalyst delivered an excellent PDH performance(propane conversion of 40.7%,propylene selectivity of 97.5%)and good cycling regeneration *** work provides a new way for improving the activity and stability of catalysts in the field of industrial catalysts.

关键词： defect engineering single platinum atom coordination environment propane dehydrogenation propylene

Additive manufacturing of NiTi lightweight porous structures bio-mimicking coral skeleton with enhanced mechanical properties and shape memory functions

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Science China Technological Sciences 2024年第8期67卷 2461-2474页

作者： LIU Xin GU DongDong YUAN LuHao ZHANG Han SUN JianFeng CHEN WenXin WANG Jie SHI KeYu Jiangsu Provincial research center for Laser Additive Manufacturing of High-Performance Components College of Materials Science and Technology Nanjing University of Aeronautics and Astronautics

Concerning the high demand for lightweight and multifunctional properties of engineering structures, the coral skeleton-inspired sheet-based（CSS） structure, which was a novel bio-mimicking coral skeleton wall-septa architecture with a unique ability to resist wave shocks was fabricated using NiTi alloy by laser powder bed fusion（LPBF） technology. The effects of laser energy density（LED） on surface morphologies, microstructures, phase transformation behavior, and mechanical properties of LPBFfabricated CSS structures were systematically investigated. The results indicated that the size deviation was predominantly governed by powder adhesion and step effect. NiTi CSS structures with LED of 71 J·mm-3possessed superior compressive modulus（～400 MPa）, ultimate strength（～13 MPa）, and energy absorption efficiency（～69%）. The compression fracture mechanism of the LPBF-fabricated NiTi CSS structures was revealed to be predominantly brittle fracture accompanied by ductile fracture. Furthermore, the Ni4Ti3nanoprecipitates induced the precipitation strengthening effect, enabling better shape memory response at LED of 71 J·mm-3, with a recoverable strain of 3.63% and recovery ratio of 90.8%, after heating under a pre-strain of 4%. This study highlights the importance of a bionic design strategy for enhancing the mechanical properties of NiTi components and offers the possibility to tailor its functional properties.

关键词： bioinspired structures laser powder bed fusion NiTi shape memory alloy mechanical performance

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The Fabrication and Detection Performance of High Sensitivity Au-Ag Alloy Nanostar/Paper Flexible Surface Enhanced Raman Spectroscopy Sensors

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Journal of Wuhan University of Technology(materials Science) 2024年第2期39卷 436-443页

作者：邓芷盈 WANG Tianyi CAO Shiyi ZHAO Yuan HAN Xiaoyu 张继红谢俊 State Key Laboratory of Silicate materials for Architectures Department of materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Hainan Institute of Wuhan University of Technology Sanya 572000China International School of materials Science and Engineering Wuhan University of TechnologyWuhan 430070China Hepu research center for Silicate materials Industry Technology Beihai 536100China

Au-Ag alloy nanostars based flexible paper surface enhanced Raman spectroscopy sensors were fabricated through simple nanostar coating on regular office paper,and the surface enhanced Raman spectroscopy detection performances were investigated using crystal violet dye ***-Ag nanostars with sharp tips were synthesized via metal ions reduction *** electron microscope images,X-Ray diffraction pattern and energy dispersive spectroscopy elemental mapping confirmed the nanostar geometry and Au/Ag components of the ***-Vis-NIR absorption spectrum shows wide local surface plasmon resonance induced optical *** addition,finite-difference time-domain simulation shows much stronger electromagnetic field from nanostars than from sphere *** effect of coating layer on Raman signal intensities was discussed,and optimized 5-layer coating with best Raman signal was *** Au-Ag nanostatrs homogeneously distribute on paper fiber *** detection limit is 10-10 M,and the relationship between analyte concentrations and Raman signal intensities shows well linear,for potential quantitative *** calculated enhancement factor is 4.795×10^(6).The flexible paper surface enhanced Raman spectroscopy sensors could be applied for trace chemical and biology molecule detection.

关键词： surface-enhanced raman gold-silver alloy nanostars paper-based SERS sensor flexibility

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Effects of Nitrogen Doping on Microstructures and Irradiation Resistance of Ti-Zr-Nb-V-Mo Refractory High-Entropy Alloy

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Acta Metallurgica Sinica(English Letters) 2024年第6期37卷 1007-1018页

作者： Huanzhi Zhang Tianxin Li Qianqian Wang Zhenbo Zhu Hefei Huang Yiping Lu Engineering research center of High Entropy Alloy materials(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Shanghai Institute of Applied Physics Chinese Academy of Sciences(CAS)Shanghai201800China

Interstitial strengthening with nitrogen(N)is one of the effective ways to improve the mechanical properties of HEAs,but the effects of N on the microstructures and mechanical properties of the irradiated HEAs have not been studied ***,the microstructures and mechanical properties of N-free and N-doped Ti_(2)ZrNbV_(0.5)Mo_(0.2)HEAs before and after He irradiation were *** results showed that the solid solution strengthening caused by interstitial N improved the yield strength at room temperature and 1023 K without significantly reducing plasticity.N doping significantly promoted the growth,aggregation and wider spatial distribution of He bubbles by enhancing the mobility of He atoms/He-vacancy complexes,with the average size of He bubbles increasing from 10.4 nm in N-free HEA to 31.0 nm in N-doped *** addition,N-doped HEA showed a much higher irradiation hardness increment and hardening fraction than N-free *** to conventional materials doped with N,the introduction of N into Ti_(2)ZrNbV_(0.5)Mo_(0.2)HEA had adverse effects on its resistance to He bubble growth and irradiation *** results of this study indicated that N doping may not improve the irradiation resistance of HEAs.

关键词： High-entropy alloys Nitrogen doping Mechanical properties Helium bubbles Irradiation resistance

EBSD analysis of grain boundary evolution and dynamic recrystallization of Inconel 625 superalloy at various hot spinning feed rates

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Progress in Natural Science:materials International 2024年第1期34卷 56-65页

作者： Zhanjie Jing Jiangkun Fan Xudong Liu Yuelin Song Zixiao Wang Kai Cao Yuetan Chen Heng Fu Jianing Zhang Jinshan Li State Key Laboratory of Solidification Processing Northwestern Polytechnical University Chongqing Innovation center Northwestern Polytechnical University National&Local Joint Engineering research center for Precision Thermoforming Technology of Advanced Metal materials

Hot spinning can make the material withstand shear stress, so that the shape of the material has a great change,which is one of the main processing methods of nickel-based alloy plate members. Inconel 625 alloy, which has excellent high temperature mechanical properties and can be used as the main candidate material for aerospace applications, needs further study on its hot spinning deformation behavior and deformation mechanism. In this paper, the effect of feed rate on the microstructure evolution of Inconel 625 superalloy was studied by the electron backscattered diffraction technology. The microstructure with necklace-like structures composed of dynamic recrystallization(DRX) grains was observed after hot spinning. It was found that at the low feed rate, the promotion of DRX degree and grain refinement happened, where the grain size reached the trough of 10.99 μm under a feed rate of 300 mm/min. However, with the further feed rate rising, the degree of DRX was suppressed to a certain extent and grain size increased to 14.26 μm. On balance, the feed rate of 300 mm/min was the most efficient condition for grain refinement. Besides, it was revealed that both discontinuous dynamic recrystallization(DDRX) and continuous dynamic recrystallization(CDRX) occurred during hot spinning. DDRX includes the initial grain boundary nucleation by bulging and the annealing twin boundary assisted nucleation, while the CDRX mechanism is related to the continuous subgrain rotation within the deformed grain. DDRX is the main DRX mechanism.

关键词： Inconel 625 superalloy Hot spinning Grain boundary evolution DRX mechanism