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Electron Beam Powder Bed Fusion Additive Manufacturing:A Comprehensive Review and its Development in China

Additive Manufacturing Frontiers 2024年第4期3卷 75-101页

作者： Mohan Jiao Hongyu Long Buwei Xiao Xiaoyu Liang Feng Lin State Key Laboratory of Clean and Efficient Turbomachinery Power Equipment Department of Mechanical EngineeringTsinghua UniversityBeijing100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationBeijing100084China Bio-Manufacturing and Rapid Forming Technology Key Laboratory of Beijing Beijing100084China State Key Laboratory of Nonferrous Metals and Specialty Materials Processing Guangxi UniversityNanning530004China

Additive manufacturing(AM),recognized as a pivotal innovation,has revolutionized the manufacturing industry since its *** a robust background of over three decades in AM,China has accomplished significant milestones,emerging as a key global player in the deployment and export of related machinery and ***’s prominence within the realm of powder bed fusion technology is underscored by its substantial market *** beam powder bed fusion(EB-PBF),known for its low residual stress and high forming efficiency,has gained considerable international *** Tsinghua University initiated the first research on EB-PBF in 2004,China has steadily advanced in this area,leading to the commercialization of EB-PBF devices and the development of a diverse product *** comprehensive review highlights the research progress in EB-PBF,focusing on its development in China,explores novel technologies,and offers insights into future advancements.

关键词： Additive manufacturing Electron beam powder bed fusion Electron beam melting Materials processing Simulation

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Mesoscale deformation mechanisms in relation with slip and grain boundary sliding in TA15 titanium alloy during tensile deformation

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Journal of Materials Science & technology 2022年第3期98卷 72-86页

作者： Yanxi Li Pengfei Gao Jingyue Yu Shuo Jin Shuqun Chen Mei Zhan State Key Laboratory of Solidification Processing Shaanxi Key Laboratory of High-Performance Precision Forming Technology and EquipmentSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China Key Laboratory of Advanced Functional Materials Education Ministry of ChinaSchool of Materials Science and EngineeringBeijing University of TechnologyBeijing 100124China

Revealing the mesoscale deformation mechanisms of titanium alloy with tri-modal microstructure is of great significance to improve its mechanical properties. In this work, the collective behavior and mechanisms of slip activities, slip transfer, and grain boundary sliding of tri-modal microstructure were investigated by the combination of quasi-in-situ tensile test, SEM, EBSD and quantitative slip trace analyses. It is found that the slip behavior presents different characteristics in the equiaxed α(α_(p)) and lamellar α(α_(l))grains. Under a low level of deformation, almost all the slip deformation is governed by single basal and prismatic slips for both of α_(p)and α_(l),despite small amount of < a >-pyramidal slip exists in α_(l)grains. As deformation proceeds, < a >-pyramidal and < c + a >-pyramidal slip systems with high Schmid factors were activated in quantities. Specially, certain coarse prismatic slip bands were produced across both of single and colony α_(l)grains whose major axes tilting about 40 °–70 ° from the tensile axis. Slip transfer occurs at the boundaries of α_(p)/α_(p)and α_(l)/β under the condition that there exists perfect alignment between two slip systems and high Schmid factors of outgoing slip system. The slip transfer across α_(l)/β boundary can be divided into two types: straight slip transfer and deflect slip transfer with a deviation angle of 5 °–12 °, depending on the alignment of slip planes of two slip systems. The grain boundary sliding along boundaries of α_(l)/β and α_(p)/β was captured by covering micro-grid on tensile sample. It is found that the crystallographic orientation and the geometrical orientation related to loading axis play great roles in the occurrence of grain boundary sliding.

关键词： Titanium alloy Tri-modal microstructure Slip modes Slip transfer Grain boundary sliding

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Elastic-viscoplastic constitutive equations of K439B superalloy and thermal stress simulation during casting process

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China Foundry 2023年第5期20卷 403-413页

作者： Da-shan Sui Yu Shan Dong-xin Wang Jun-yi Li Yao Xie Yi-qun Yang An-ping Dong Bao-de Sun Institute of Forming Technology&Equipment School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200030China State Key Laboratory of Special Rare Metal Materials Northwest Rare Metal Materials Research Institute Ningxia Co.Ltd.Shizuishan 753000NingxiaChina Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China

K439B nickel-based superalloy is a new type of high-temperature *** is insufficient research on its constitutive equations and numerical modeling of thermal *** tensile experiments of K439B superalloy at different temperatures(20°C-1,000°C)and strain rates(1.33×10^(-3)s^(-1)-5.33×10^(-3)s^(-1))were performed by using a Gleeble-3800 *** elastic moduli at different temperatures(20°C-650°C)were measured by resonance ***,stress-strain curves were measured for K439B superalloy under different *** elastic-viscoplastic constitutive equations were established and the correspongding parameters were solved by employing the Perzyna *** verification results indicate that the calculated values of the constitutive equations are in good agreement with the experimental *** this basis,the influence of process parameters on thermal stress was investigated by numerical simulation and orthogonal experimental *** results of orthogonal experimental design reveal that the cooling mode of casting has a significant influence on the thermal stress,while pouring temperature and preheating temperature of shell mold have minimal *** distribution of physical fields under optimal process parameters,determined based on the orthogonal experimental design results,was *** simulation results determine separately the specific positions with maximum values for effective stress,plastic strain,and displacement within the *** maximum stress is about 1,000.0 MPa,the plastic strain is about 0.135,and the displacement is about 1.47 ***,the distribution states of thermal stress,strain,and displacement are closely related to the distribution of the temperature gradient and cooling rate in the *** research would provide a theoretical reference for exploring the stress-strain behavior and numerical modeling of the effective stress of the alloy during the casting process.

关键词： nickel-based superalloy investment casting Perzyna model elastic-viscoplastic thermal stress numerical simulation

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Anomalous enhancing effects of electric pulse treatment on strength and ductility of TC17 linear friction welding joints

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Journal of Materials Science & technology 2024年第36期203卷 155-166页

作者： Xin Zhang Junjie Zhang Yunkui Yao Qingsong Qiao Lixing Zhao Leichang Liu Feng Jin Mei Zhan Hongwei Li Key Laboratory of High-Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Polytechnical UniversityXi’an 710072China Engineering Research Center of Advanced Manufacturing Technology for Aero Engine Ministry of EducationNorthwestern Polytechnical UniversityXi’an 710072China Shaanxi Key Laboratory of High-Performance Precision Forming Technology and Equipment Northwestern Polytechnical UniversityXi’an 710072China School of Materials Science and Engineering Jiangsu UniversityZhenjiang 212013China State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Mechanical properties of TC17 titanium alloy undergo a significant reduction after linear friction welding(LFW),of which the strength and ductility are hard to be improved simultaneously by traditional aging heat treatment(AHT),seriously limiting the application of LFW in the manufacturing of TC17 titanium alloy *** this end,the present work proposes to use electric pulse treatment(EPT)to enhance the strength and ductility of TC17 LFW joints simultaneously by improving its *** results show that,in comparison to the uneven distribution ofαphases in the welding zone(WZ),heat-affected zone(HAZ),and base metal(BM)zone after AHT,EPT can selectively homogenize theαphase distribution of WZ and HAZ without impacting the *** selective effect of EPT is reflected as the synergistic influence of the local Joule heating effect and the electron wind effect,which promotes the diffusion ofβphase stabilizing element Mo and leads to a competitive precipitation ofβphase andαphase in theαphase transition temperature *** ratio ofαphase toβphase in the WZ and HAZ finally approaches an equilibrium point which is similar to that of BM,leading to a uniform distribution ofαphase and realizing the synergy of strength-ductility of LFW joint:the maximum strength increase observed is 12.9%,accompanied by a corresponding elongation increase of 122%(by AHT&EPT),and the maximum plasticity improvement is 185%,accompanied by a corresponding strength increase of 4.3%(by EPT for 1 h).This study provides essential insights for improving the strength and ductility of LFW TC17 titanium alloy blisks and enhancing the applications of LFW in aeroengine components.

关键词： Linear friction welding TC17 titanium alloy Electric pulse treatment Phase transformation Local joule heating effect

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Study on the effect of fiber tension on the tensile properties of CAF/PA12 composites 9

Study on the effect of fiber tension on the tensile properti...

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9th International Conference on Mechanical Engineering, Materials, and Automation technology, MMEAT 2023

作者： Zou, Dongming Shan, Zhongde Liu, Feng Ren, Yongxin Wu, Siyuan Jiang, Xibin State Key Laboratory of Advanced Forming Technology and Equipment China Academy of Machinery Science and Technology Beijing100044 China Beijing National Innovation Institute of Lightweight Ltd. China

ISBN: (纸本)9781510668584

The lack of fiber restraint during the preparation of continuous fiber-reinforced thermoplastic resin composite filaments makes the fibers inside the composite filaments prone to curl and deflection, which affects the mechanical properties of the composites. This study aimed to investigate the impact of fiber tension on the tensile properties of continuous aramid fiber (CAF)/nylon 12(PA12) resin composite filaments and molded parts. Tensile properties experiments of tensile specimens were conducted in conjunction with acoustic emission (AE) instruments and computed tomography (CT). The results showed that the tensile properties of the CAF/PA12 composite filament and its specimens rose first with the increasing of fiber tension during the filament preparation and then fell. The tensile strength of the CAF/PA12 composite filament reached the maximum value of 1272.05 MPa at the fiber tension of 3 N, which was about 15.92% higher than that without fiber tension, the maximum tensile breaking load of the tensile specimens is 15.31kN, which is about 16.47% higher than that without fiber tension. Using AE to collect the energy signal during the damage process. It is observed that the medium energy signal appears lagged when the fiber tension is too high, when there is a hysteresis in the medium energy signal, which means that the strength of the interfacial bond between the fiber and the resin is increased. CT scans of the composite filaments prepared at different fiber tensions revealed that when the fiber tension increased from 0N to 3N, the bent fibers inside the filaments decreased and the fiber orientation coefficient increased;when the fiber tension was further increased to 5N, some fibers broke and more pores appeared inside the filaments. © 2023 SPIE.

关键词： 3D printing

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Influence of cooling speeds on the microstructure and properties of A356 aluminum alloy after squeeze casting 9

Influence of cooling speeds on the microstructure and proper...

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2023 9th International Forum on Manufacturing technology and Engineering Materials, ICMTEM 2023

作者： Li, Chun-Ming Zuo, Ling-Li Li, Long-Fei Liang, Jun-Ning Zhang, Yang Chen, Lin Zhao, Xue-Sheng Han, Qing-Hua Beijing National Innovation Institute of Lightweight Ltd State Key Laboratory of Advanced Forming Technology and Equipment Beijing100083 China Hebei Fengwei Machinery Co. Ltd. Hebei Xingtai154500 China

The examination focuses on the microstructural characteristics and mechanical attributes of A356 alloy subsequent to squeeze casting performed under varying cooling speeds. The findings reveal that the cooling speeds have no notable impact on the size of the grains in the A356 alloy produced through squeeze casting. However, as the cooling speeds increase, the eutectic Si phase in A356 alloy decreases, transforming it from coarse flakes to small rods or particles, thereby enhancing the mechanical characteristics of the alloy. The water-cooled alloy has the best UTS performance, whose value of A356 alloy after squeeze casting is 287 MPa. © Published under licence by IOP Publishing Ltd.

关键词： Squeeze casting

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The influence of the hot-pressing process on the mechanical properties of continuous aramid fiber-reinforced PA12 composites 4

The influence of the hot-pressing process on the mechanical ...

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2024 4th International Conference on advanced Materials and Mechatronics, IcamM 2024

作者： Yong, Moxuan Du, Bing Jiang, Xibin Beijing National Innovation Institute of Lightweight Ltd Beijing100083 China State Key Laboratory of Advanced Forming Technology and Equipment China Academy of Machinery Science and Technology Beijing100044 China China Academy of Machinery Science and Technology Beijing100044 China

Hot-pressing post-treatment can effectively improve the mechanical properties of composite specimens. In order to improve the impact resistance of continuous aramid fiber-reinforced nylon 12 (CAF/PA12) composites, the effect of hot-pressing parameters on the interlaminar shear strength of the composite was studied. The effects of hot-pressing temperature, hot-pressing time, and hot-pressing pressure on the interlaminar shear strength of composite formed specimens were studied by single factor test. Based on the optimized parameters of hot-pressing, the influence of hot-pressing on low-speed impact performance was analyzed. The results shown that the interlaminar shear strength first increased and then decreased with the increase of hot-pressing temperature and pressure. With the extension of hot-pressing time, the interlaminar shear strength continued to increase. When the hot-pressing parameters were 170°C, 30 min, and 600 kPa, the shear strength and specimen quality were the best. Under this hot-pressing process, the low-speed impact performance was increased by 36.0%. In this paper, the research content of the hot-pressing process of composite materials was expanded, which provided a reference for the research of impact resistance of continuous aramid fiber-reinforced PA12 composite materials. © Published under licence by IOP Publishing Ltd.

关键词： Aramid fibers

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Thickness Distribution Prediction of Superplastic forming Parts Based on Machine Learning and Computer Aided Engineering 4

Thickness Distribution Prediction of Superplastic Forming Pa...

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4th International Symposium on Artificial Intelligence and Intelligent Manufacturing, AIIM 2024

作者： Sun, Muqi Xiong, Chengyue Zhou, Yuwei Li, Yongbing Zhang, Xicheng China Academy of Machinery Science and Technology Beijing China State Key Laboratory of Advanced Forming Technology and Equipment China Academy of Machinery Science & Technology Beijing China Beijing National Innovation Institute of Lightweight Ltd China Academy of Machinery Science & Technology Beijing China

ISBN: (纸本)9798331541729

In recent years, the high-speed and high-performance needs of aircraft put forward higher requirements for superplastic forming process, in which uneven thickness distribution is one of the important factors affecting the performance of formed parts, and it increases the cost of design and manufacturing. Therefore, this study proposes using neural networks to predict the thickness distribution of superplastic formed parts. We established BP neural network and PSO-BP neural network to predict the thickness distribution of cross-section edges of box-shaped parts. The prediction performance of the two models is compared and the results show that the PSO-BP neural network has a higher prediction accuracy, especially in the area of the round corners. It is demonstrated that the method is feasible and significantly improves the computational efficiency. © 2024 IEEE.

关键词： Superplasticity

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Engineering design of feedstock powder and relevant thermal-mechanical performance of thermal/environmental barrier coatings

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Journal of advanced Ceramics 2025年第2期14卷 37-56页

作者： Xinchang Feng Fangwei Guo Lirong Luo Yuzhang Wang Yun Long Xiaofeng Zhao Fei Pan Lei Guo Qingfeng Zeng Jing Feng Chunlei Wan Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240China National Engineering Research Center of Special Equipment and Power System for Ship and Marine Engineering Shanghai 200030China School of Mechanical Engineering Shanghai Jiao Tong UniversityShanghai 200240China State Key Laboratory of Advanced Nuclear Energy Technology Nuclear Power Institute of ChinaChengdu 610213China Innovative Sensor Technology IST AG Ebnat-Kappel 9642Switzerland School of Materials Science and Engineering Tianjin UniversityTianjin 300072China Tianmushan Laboratory Hangzhou 311115China School of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China State Key Laboratory of New Ceramics and Fine Processing School of Materials Science and EngineeringTsinghua UniversityBeijing 100084China

The development of aeroengine with a high thrust-weight ratio poses great challenges for current top-coating thermal barrier coatings (TBCs) and environmental barrier coatings (EBCs) in service. Medium/high-entropy ceramics are highly promising candidate material for advanced TBCs/EBCs owing to their low thermal conductivity, high melting point, high-temperature stability, and calcium–magnesium–alumino–silicate (CMAS) resistance. Most feedstock powder used for medium/high-entropy TBCs/EBCs is prepared via traditional spray drying, which cannot fully exploit the advantages of multicomponent ceramics. The density, sphericity, inner structure, and flowability of feedstock powder affect their melting state during the thermal spraying process, which strongly affects the microstructure and properties of the deposited coatings. Therefore, the deposited coatings exhibit phase segregation, amorphous phases, and microstructure defects owing to unpredictable variations in feedstock powder with random morphologies and structures. Here, the structure and properties of feedstock powder prepared by state-of-the-art granulation technologies and their influences on the deposited coatings were systematically investigated, which can provide guidance for configuration optimization of feedstock powder and the manufacturing accuracy of the deposited coating. This review aims to bridge the gap between cutting-edge ceramics and advanced engineering technologies, thus providing concrete background knowledge and crucial guidelines for designing and developing TBCs/EBCs.

关键词： thermal/environmental barrier coatings(TBCs/EBCs) spraying ceramic powder multiscale structure control high-entropy ceramics thermal-mechanical performance

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Simulation and experimental research on extra-squeeze forming method during gradient sand molding

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China Foundry 2022年第4期19卷 288-298页

作者： Er-biao Jiang Zhong-de Shan Guang Cheng Shao-zong Wang Zhao-xian Gu Xin-lei Wang State Key Laboratory of Advanced Forming Technology and Equipment China Academy of Machinery Science and Technology Group Co.Ltd.Beijing 100044China Nanjing University of Aeronautics and Astronautics Nanjing 210016China Beijing Union University Beijing 100101China

The flexible extrusion forming process (FEFP) is a sand mold patternless manufacturing technology that enables digital near-net shaping of complex sand molds. But, it is difficult to achieve the gradient sand molds with high surface strength and strong interior permeability by FEFP. To solve this problem, an extra-squeeze forming method based on FEFP for gradient sand mold was developed. To further reveal the extra-squeeze forming mechanism, based on the Johnson-Kendall-Roberts (JKR) theory and “gluing” notions, the single and double-sided squeeze models of gradient sand molds were established using the EDEM software. The squeezing processes of sand molds with different cavity depths of 60, 100, 140, 180, and 220 mm were systemically studied under single and double-sided squeeze conditions. The variation in the void fraction of sand mold as also investigated at a variety of extra-squeeze distances of 2, 3, 4, 5, and 6 mm, respectively. Simulation and test results show that a deeper cavity depth weakens the extrusion force transmission, which leads to a decrease in strength. The sand mold permeability and void fraction are identified to be positively correlated, while the tensile strength and void fraction appear to be negatively correlated. The void fraction of sand molds decreases with a longer extra-squeeze distance. A 6 mm extra-squeeze distance for the sand mold with 220 mm cavity depth results in a 26.8% increase in tensile strength with only a 5.7% reduction in the permeability. Hence, the extra- squeeze forming method can improve the quality of the sand mold by producing a gradient sand mold with high surface strength and strong interior permeability.

关键词： patternless casting gradient squeeze sand mold performance discrete element simulation void fraction

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