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Comparison of irradiation-induced void formations in tungsten with equiaxed and columnar structures

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Tungsten 2024年第4期6卷 794-805页

作者： Liu Xi Jia-Jun Zhao Ji-Jun Zhao Yuan-Yuan Wang Key Laboratory of Materials Modification by laser Ion and Electron Beams(Ministry of Education) Dalian University of Technology

Tungsten(W) has been received much attention,since it is regarded as one of the most promising plasma facing materials for fusion *** are two typical morphologies of unirradiated polycrystalline W,which have the equiaxed and columnar grains,***,the role of arrangement of grain boundary(GB) in absorbing irradiation-generated point defects is still waiting to be *** current investigation,irradiation-induced void formations in W with equiaxed and columnar microstructures are predicted,respectively,using the developed phase-field *** significant kinetic behavior,such as the generation and annihilation of point defects and the interaction between point defects and GB,is reasonably *** density,size and porosity of void formed in these two microstructures are examined and analyzed according to the effects of GB ratio,temperature and damage *** analytical results show that higher GB ratio can effectively reduce void porosity,and the columnar-grained structure has better irradiation resistance than that of the equiaxed one in the case of small grain *** importantly,the predicted void sizes changed with temperature and damage rate agree well with the experimentally measured *** work has a more beneficial contribution to the microstructural improvement of International Thermonuclear Experimental Reactor-grade W.

关键词： Grain morphology Irradiation-induced void Phase-field Tungsten

Hot Compression Behavior and Tensile Property of a Novel Ni-Co-Based Superalloy Prepared by electron Beam Smelting Layered Solidification Technology

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Acta Metallurgica Sinica(English Letters) 2024年第2期37卷 283-292页

作者： Yong-Chao Gai Rui Zhang Chuan-Yong Cui Zi-Jian Zhou Yi Tan Yi-Zhou Zhou Xiao-Feng Sun Key Laboratory of Materials Modification by laser Ionand Electron Beams(Ministry of Education)School of Materials Science and EngineeringDalian University of TechnologyDalian116024China Shi-Changxu Innovation center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

The hot compression behavior and tensile strength after compression of a new Ni-Co-based superalloy produced using electron beam smelting layered(EBSL)solidification technology were *** compression tests were performed at temperatures of 1120℃and 1150℃,with strain rates of 1 s^(-1) and 0.01 s^(-1),reaching a true strain of *** strength was evaluated at room *** results revealed that this EBSL technology accelerates dynamic recrystallization(DRX),without compromising the strength of alloy.A significant correlation between the volume fraction of DRX and the strain rate was observed,with higher fractions at lower strain rates,leading to higher tensile ***,at the same strain rate,the specimens compressed at 1120℃exhibited higher tensile strength due to undissolvedγ′*** solution and aging heat treatment,the alloy maintained high tensile *** results suggested that the EBSL Ni-Co-based superalloy offers excellent prospects for practical applications.

关键词： Ni-Co-based superalloy Hot deformation electron beam smelting Tensile strength

General synthesis of transition metal nitride arrays by ultrafast flash Joule heating within 500 ms

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science China Chemistry 2024年第6期67卷 1976-1982页

作者： Peiqi Shen Jiahui Zhao Yanan Gao Yunxiang Lin Yuchen Han Kun Xu School of Chemistry and Chemical Engineering Key Laboratory of Functional Inorganic Material Chemistry of Anhui ProvinceAnhui Province Key Laboratory of Chemistry for Inorganic/Organic Hybrid Functionalized MaterialsKey Laboratory of Structure and Functional Regulation of Hybrid Materials of Ministry of EducationAnhui UniversityHefei230601China Institutes of Physical science and Information Technology Center of Free Electron Laser&High Magnetic FieldLeibniz International Joint Research Center of Materials Sciences of Anhui ProvinceAnhui UniversityHefei230601China

Transition metal nitrides(TMNs)are considered as viable alternatives to noble metal catalysts owing to their versatile electronic structure and favorable catalytic ***,the conventional synthetic processes for TMNs suffer from high energy consumption and low production *** this study,a range of TMNs and their hetero-composite arrays were successfully synthesized via an ultrafast flash Joule heating technology within 0.5 *** a proof concept,the nitrides and hetero-composites were applied for the electrocatalytic hydrazine oxidation reaction(HzOR),in which the Co_(4)N/Mo_(16)N_(7)arrays shows the best performance with a geometric current density of 100 mA cm^(-2)at 23 mV(*** hydrogen electrode(RHE)).This work paves a new way for the ultrafast synthesis of TMNs which could meet the ever-increased energy crisis.

关键词： flash Joule heating rapid synthesis transition metal nitrides hydrazine oxidation reaction electrocatalysts

Power transfer efficiency in an air-breathing radio frequency ion thruster

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Chinese Physics B 2024年第7期33卷 430-438页

作者：黄高煌李宏高飞王友年 Key Laboratory of Materials Modification by laser Ionand Electron Beams(Ministry of Education)School of PhysicsDalian University of TechnologyDalian 116024China College of Physical science and Technology Dalian UniversityDalian 116622China

Due to a series of challenges such as low-orbit maintenance of satellites, the air-breathing electric propulsion has got widespread attention. Commonly, the radio frequency ion thruster is favored by low-orbit missions due to its high specific impulse and efficiency. In this paper, the power transfer efficiency of the radio frequency ion thruster with different gas compositions is studied experimentally, which is obtained by measuring the radio frequency power and current of the antenna coil with and without discharge operation. The results show that increasing the turns of antenna coils can effectively improve the radio frequency power transfer efficiency, which is due to the improvement of Q factor. In pure N_2 discharge,with the increase of radio frequency power, the radio frequency power transfer efficiency first rises rapidly and then exhibits a less steep increasing trend. The radio frequency power transfer efficiency increases with the increase of gas pressure at relatively high power, while declines rapidly at relatively low power. In N_(2)/O_(2) discharge, increasing the N_(2) content at high power can improve the radio frequency power transfer efficiency, but the opposite was observed at low power. In order to give a better understanding of these trends, an analytic solution in limit cases is utilized, and a Langmuir probe was employed to measure the electron density. It is found that the evolution of radio frequency power transfer efficiency can be well explained by the variation of plasma resistance, which is related to the electron density and the effective electron collision frequency.

关键词： radio frequency ion thruster inductively coupled plasma power transfer efficiency analytic solution

Microscopic nonlinear optical activities and ultrafast carrier dynamics in layered AgInP_(2)S_(6)

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Photonics Research 2024年第4期12卷 691-700页

作者： ZIXIN WANG NINGNING DONG YU MAO CHENDUAN CHEN XIN CHEN CHANG XU ZHOUYUAN YAN JUN WANG Aerospace laser Technology and Systems Department CAS Key Laboratory of Materials for High-Power LaserShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China center of Materials science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China CAS center for Excellence in Ultra-intense laser science(CEULS) State Key Laboratory of High Field Laser PhysicsShanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghai 201800China

Since the emergence of graphene, transition metal dichalcogenides, and black phosphorus, two-dimensional materials have attracted significant attention and have driven the development of fundamental physics and optoelectronic devices. Metal phosphorus trichalcogenides(MPX3), due to their large bandgap of 1.3–3.5 eV, enable the extension of optoelectronic applications to visible and ultraviolet(UV) wavelengths.

关键词： nonlinear ultraviolet phosphorus

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

Continuous gradient fusion class activation mapping: segmentation of laser-induced damage on large-aperture optics in dark-field images

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High Power laser science and Engineering 2024年第1期12卷 30-41页

作者： Yueyue Han Yingyan Huang Hangcheng Dong Fengdong Chen Fa Zeng Zhitao Peng Qihua Zhu Guodong Liu School of Instrumentation science and Engineering Harbin Institute of TechnologyHarbinChina Research center of laser Fusion China Academy of Engineering PhysicsMianyangChina

Segmenting dark-field images of laser-induced damage on large-aperture optics in high-power laser facilities is challenged by complicated damage morphology, uneven illumination and stray light interference. Fully supervised semantic segmentation algorithms have achieved state-of-the-art performance but rely on a large number of pixel-level labels, which are time-consuming and labor-consuming to produce. LayerCAM, an advanced weakly supervised semantic segmentation algorithm, can generate pixel-accurate results using only image-level labels, but its scattered and partially underactivated class activation regions degrade segmentation performance. In this paper, we propose a weakly supervised semantic segmentation method, continuous gradient class activation mapping(CAM) and its nonlinear multiscale fusion(continuous gradient fusion CAM). The method redesigns backpropagating gradients and nonlinearly activates multiscale fused heatmaps to generate more fine-grained class activation maps with an appropriate activation degree for different damage site sizes. Experiments on our dataset show that the proposed method can achieve segmentation performance comparable to that of fully supervised algorithms.

关键词： class activation maps laser-induced damage semantic segmentation weakly supervised learning

Effect of high-energy Ne ions irradiation on mechanical properties difference between Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5)metallic glass and crystalline W

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Plasma science and Technology 2024年第6期26卷 14-21页

作者：李娜张立松张小楠宫丽悦羌建兵梅显秀 Key Laboratory of Materials Modification by laser Ion and Electron BeamsMinistry of EducationDalian University of TechnologyDalian 116024People’s Republic of China School of science Dalian Jiaotong UniversityDalian 116028People’s Republic of China

In this paper,high-energy Ne ions were used to irradiate Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) metallic glass(MG)and crystalline W to investigate their difference in mechanical response after *** results showed that with the irradiation dose increased,the tensile micro-strain increased,nano-hardness increased from 7.11 GPa to 7.90 GPa and 8.62 GPa,Young’s modulus increased,and H3/E2 increased which indicating that the plastic deformability decreased in crystalline *** the same irradiation conditions,the Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG still maintained the amorphous structure and became more disordered despite the longer range and stronger displacement damage of Ne ions in Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG than in crystalline *** the irradiation hardening and embrittlement behavior of crystalline W,Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG showed the gradual decrease in hardness from 6.02 GPa to 5.89 GPa and 5.50 GPa,the decrease in modulus and the increase in plastic deformability with the increasing ***,the irradiation softening and toughening phenomenon of Zr_(63.5)Cu_(23)Al_(9)Fe_(4.5) MG could provide new ideas for the design of nuclear materials.

关键词： heavy ions irradiation displacement damage metallic glass crystalline W mechanical property

Non-blind super-resolution reconstruction for laser-induced damage dark-field imaging of optical elements

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Chinese Optics Letters 2024年第4期22卷 36-41页

作者：王倩陈凤东韩越越曾发路程刘国栋 Instrument science and Technology Harbin Institute of TechnologyHarbin 150001China Research center of laser Fusion China Academy of Engineering PhysicsMianyang 621900China

The laser-induced damage detection images used in high-power laser facilities have a dark background,few textures with sparse and small-sized damage sites,and slight degradation caused by slight defocus and optical diffraction,which make the image superresolution(SR)reconstruction *** propose a non-blind SR reconstruction method by using an exquisite mixing of high-,intermediate-,and low-frequency information at each stage of pixel reconstruction based on *** simplify the channel attention mechanism and activation function to focus on the useful channels and keep the global information in the *** pay more attention on the damage area in the loss function of our end-toend deep neural *** constructing a high-low resolution image pairs data set,we precisely measure the point spread function(PSF)of a low-resolution imaging system by using a Bernoulli calibration pattern;the influence of different distance and lateral position on PSFs is also considered.A high-resolution camera is used to acquire the ground-truth images,which is used to create a low-resolution image pairs data set by convolving with the measured *** on the data set,our network has achieved better results,which proves the effectiveness of our method.

关键词： laser-induced damage image superresolution image segmentation