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Single-sensor-based reconstruction of force and displacement fields for thin-walled cylindrical shells milling

International Journal of Machine Tools and Manufacture 2025年 208卷

作者： Chen, Jie Ma, Haifeng Song, Qinghua Cai, Yukui Liu, Zhanqiang School of Mechanical Engineering Shandong University Jinan250061 China State Key Laboratory of Advanced Equipment and Technology for Metal Forming Shandong University Jinan250061 China Key Laboratory of High Efficiency and Clean Mechanical Manufacture of Ministry of Education Jinan250061 China Key National Demonstration Center for Experimental Mechanical Engineering Education Jinan250061 China School of Mechanical Electrical & Information Engineering Shandong University Weihai264209 China

The cutting process of thin-walled cylindrical shells involves complex working conditions, and it is difficult to measure the cutting force and vibration displacement at the cutting point in real time. To address this issue, a method is proposed to reconstruct the force and displacement fields of the cylindrical shell in real time using only a single displacement sensor. Based on the first-order shear deformation theory and the artificial spring technique, the wave method can be employed to simultaneously obtain the natural frequencies and analytical mode shape functions of the cylindrical shell with elastic boundary. The dynamic behavior of the cylindrical shell is characterized by the superposition of mode shapes, thereby determining the force-displacement mapping relationship for the entire cylindrical shell. Utilizing in-situ measurement, the time-varying force and displacement fields are reconstructed in real time. Unlike existing methods for reconstructing the displacement field of thin-walled workpieces, one unique feature of this study is the simultaneous real-time reconstruction of the force and the displacement fields using single-point measurement information, providing higher reconstruction accuracy with fewer sensors, thus ensuring practicality and reliability of the results. Through simulation and experimental application to the force and displacement fields reconstruction of cylindrical shell under concentrated and moving force (e.g., cutting process), its practicality as a real-time tool for continuously monitoring cutting force and displacement of cylindrical shell during the cutting process has been demonstrated. © 2025 Elsevier Ltd

关键词： Position measurement

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Formation Mechanism of Inclusion Defects in Large Forged Pieces

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Journal of Iron and Steel Research International 2016年第6期23卷 531-538页

作者： Rong-sheng QI Miao JIN Xin-gang LIU Bao-feng GUO Key Laboratory of Advanced Forging and Stamping Technology and Science of Ministry of Education Yanshan University

Nonmetallic inclusions mixed into large forged metal objects destroy the continuity in the metal and affect the quality of the forged *** on how inclusions affect the plastic deformation of a matrix shows the significance of the formation mechanism of inclusion *** upset forging,the nonlinear finite element model was shown to be appropriate for the ingot hot-forging process by comparing the results with experiments involving plastic and hard inclusions inserted into the forged *** high-temperature stress-strain curves of MnS plastic inclusions were obtained *** results show how,during upsetting,the morphology of MnS plastic inclusions varies from spherical to ellipsoidal,until finally becoming flat in *** larger the inclusion is,the larger the degree of deformation of the inclusion is,and large inclusions enhance the risk of the final product failing to pass inspection for inclusion *** significantly concentrates in the matrix near a hard *** the hard inclusion reaches a certain size,conical fractures form on both sides of the *** pass inclusion-flaw inspection and close hole defects to the extent possible,the flat-anvil upsetting is ***,the inclusiondeformation state obtained by finite element simulation is verified experimentally.

关键词： inclusion inspection anvil spherical destroy continuity forging finally verified ingot

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Enhanced heat transfer on hollow hierarchical nanowired surface during transient spray cooling of liquid nitrogen

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International Communications in Heat and Mass Transfer 2025年 165卷

作者： Fan, Yiming Su, Fengmin Peng, Jiahui Fan, Letian Chang, Chao Ji, Yulong Wen, Rongfu Zhu, Guoliang Institute of Marine Engineering and Thermal Science Dalian Maritime University Liaoning Province Dalian116026 China State Key Laboratory of Fine Chemicals Frontier Science Center for Smart Materials Dalian University of Technology Liaoning Province Dalian116024 China Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai200240 China

The liquid spreading and replenishment has a key effect on the performance of transient spray cooling. In this study, we used liquid nitrogen as the working fluid and conducted transient spray cooling experiments on four modified copper surfaces, including superhydrophilic surface, hydrophilic surface, smooth copper surface, and hollow hierarchical nanowired surface. The results show that increasing the single-scale surface hydrophilicity of the copper surface can effectively increase the critical heat flux (CHF) of liquid nitrogen transient spray cooling, due to the effective enhancement of evaporation heat transfer coefficient h. The multi-scale hollow hierarchical structure surface can further enhance the heat transfer of liquid nitrogen transient spray cooling, its cooling rate is accelerated 1.3 times, the CHF is increased 1.2 times and the maximum hMAX is increased 1.11 times that of the superhydrophilic surface. Through the calculation of the liquid film climb theory model, it was found that the liquid nitrogen film climbs at a speed of 48.10 m/s in the nanowired clusters. The ultrafast climb of liquid nitrogen film in hierarchical nanowires may be one of the main reasons for enhanced heat transfer. This study broadens the experimental database of hierarchical structure surfaces and new ideas on enhanced heat transfer during cryogenic spray cooling. © 2025 Elsevier Ltd

关键词： Nanowires

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Oxidation behavior and failure mechanism of NiCoCrAl eutectic multi-principal element alloys co-doped with Y and Hf at 1100 °C and 1200 °C

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Corrosion Science 2025年 253卷

作者： Huang, Aihui Yang, Chao Liu, Xuanzhen Zhang, Han Guo, Fangwei Qian, Bingnan Lu, Jie Zhao, Xiaofeng Chu, Paul K. Shanghai Key Laboratory of Advanced High-Temperature Materials and Precision Forming School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai200240 China National Engineering Research Center of Light Alloy Net Forming Shanghai Jiao Tong University China National Key Laboratory of Nuclear Reactor Technology Nuclear Power Institute of China Chengdu610213 China Department of Physics Department of Materials Science & Engineering and Department of Biomedical Engineering City University of Hong Kong Tat Chee Avenue Kowloon Hong Kong

This study investigates the oxidation behavior of Y/Hf co-doped NiCoCrAl-type EMPEAs with various Co and Cr concentrations (Ni59.6Co10Cr10Al20.4, Ni50.7Co15Cr15Al19.3 and Ni33.4Co25Cr25Al16.6 in at%) at 1100 °C and 1200 °C. After oxidation at 1100 °C, increasing Co and Cr contents enhances Y/Hf solubility in the β phase, which delays the θ- to α-Al2O3 phase transformation and promotes the formation of larger columnar grains of α-Al2O3 scale, thereby reducing the oxidation rate by up to 62 %. After oxidation at 1200 °C, the NiCoCrAl-type EMPEAs with higher Co and Cr content show significantly better spallation resistance due to the reduction of the coefficient of thermal expansion (CTE) and Y/Hf solubility in the γ phase. This reduction minimizes residual stress in the oxide scale and decreases the tendency for oxide intrusion at the scale/alloy interface, thereby enhancing the interfacial fracture energy. These findings provide scientific guidance for optimizing the composition of NiCoCrAl EMPEAs to enhance oxidation resistance in high-temperature applications. © 2025 Elsevier Ltd

关键词： Fracture energy

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Novel Mobility Formula for Parallel Mechanisms Expressed with Mobility of General Link Group

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Chinese Journal of Mechanical Engineering 2013年第6期26卷 1082-1090页

作者： ZHANG Yitong LU Wenjuan MU Dejun YANG Yandong ZHANG Lijie ZENG Daxing Key Laboratory of Parallel Robot and Mechatronic System Yanshan University Key Laboratory of Advanced Forging & Stamping Technology and Science Yanshan University

The determination of virtual constraints is always one of the key and difficult problems in traditional mobility calculation. To make mobility calculation simple, considering avoiding virtual constraints, some new formulae have been presented, however these formulae can hardly intuitively reflect general link group＇s restrictions on output member and its influences on independence of output parameters, which is premise to the judgment of the properties of mobility. Towards the problem to reveal the intrinsic relationship between the degree of freedom（DOF） of a mechanism, the link group, and the dimension of output parameters, also to avoid determination of virtual constraint, based on the new concepts of the ＂DOF of general link group＂ and ＂node parameters＂, a new formula in the calculation of the mobility of mechanisms is presented that is expressed with DOFs of the general link groups and rank of motion parameters of base point of the output link. It is named GOM（mobility of groups and output parameter） formula. On the basis of new concepts of＂effective parameters＂ and ＂invalid parameters＂, a rule is put forward for solving the DOF of mechanisms with invalid parameters by GOM formula, that is, the base point parameters are the subset of effective parameters of link group. Thereafter, several examples are enumerated and the results coincide with the prototype data, which proves the validity of the proposed formula. Meanwhile, it is obtained that the necessary and sufficient condition for the judgment of output parameters independence is that each of the DOF of the link group is not less than zero. The proposed formula which is simple in calculation provides theoretical basis for the judgment of independence of output parameters and provides references for type synthesis of novel parallel mechanisms with independence requirements of their output parameters.

关键词： parallel mechanism degree of freedom general link group output parameters

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Concurrently bioprinted scaffolds with autologous bone and allogeneic BMSCs promote bone regeneration through native BMSC recruitment

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Bio-Design and Manufacturing 2025年第1期8卷 85-99,I0042,I0043页

作者： Yu Huan Hongqing Chen Dezhi Zhou Xin He Sanzhong Li Xiuquan Wu Bo Jia Yanan Dou Xiaowei Fei Shuang Wu Zhou Fei Tao Xu Fei Fei Department of Neurosurgery Xijing HospitalAir Force Medical UniversityXi’an 710032China Department of Neurosurgery General Hospital of Northern Theater CommandShenyang 110840China Biomanufacturing and Rapid Forming Technology Key Laboratory of Beijing Department of Mechanical EngineeringTsinghua UniversityBeijing 100084China Key Laboratory for Advanced Materials Processing Technology Ministry of EducationDepartment of Mechanical EngineeringTsinghua UniversityBeijing 100084China Department of Precision Medicine and Healthcare Tsinghua Berkeley Shenzhen InstituteShenzhen 518055China Center for Bio-intelligent Manufacturing and Living Matter Bioprinting Research Institute of Tsinghua University in ShenzhenShenzhen 518057China Department of Ophthalmology Xijing HospitalAir Force Medical UniversityXi’an 710032China

Autologous bone marrow-derived mesenchymal stem cells(BMSCs)have been shown to promote osteogenesis;however,the effects of allogeneic BMSCs(allo-BMSCs)on bone regeneration remain ***,we explored the bone regeneration promotion effect of allo-BMSCs in 3D-printed autologous bone particle(ABP)***,we concurrently printed scaffolds with polycaprolactone,ABPs,and allo-BMSCs for appropriate support,providing bioactive factors and seed cells to promote *** vitro studies showed that ABP scaffolds promoted allo-BMSC osteogenic *** vivo studies revealed that the implantation of scaffolds loaded with ABPs and allo-BMSCs into canine skull defects for nine months promoted *** experiments suggested that only a small portion of implanted allo-BMSCs survived and differentiated into vascular endothelial cells,chondrocytes,and *** implanted allo-BMSCs released stromal cell-derived factor 1 through paracrine signaling to recruit native BMSCs into the defect,promoting bone *** study contributes to our understanding of allo-BMSCs,providing information relevant to their future application.

关键词： Concurrent 3D bioprinting Cranioplasty Autologous bone particles Allogeneic mesenchymal stem cells Recruitment

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On the strain and strain-rate hardenability of additively manufactured austenitic stainless steels

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Materials Science and Engineering: A 2025年 939卷

作者： Kong, Decheng Xu, Xuexu Ni, Xiaoqing Zhu, Guoliang Dong, Chaofang Shanghai Key Laboratory of Advanced High-temperature Materials and Precision Forming School of Materials Science and Engineering Shanghai Jiao Tong University Shanghai200240 China Beijing Advanced Innovation Center for Materials Genome Engineering Institute for Advanced Materials and Technology University of Science and Technology Beijing Beijing100083 China Research and Application Center of Additive Manufacturing Materials Shanghai Research Institute of Materials Co. Ltd. Shanghai200437 China

Dislocation cells (DCs) are peculiar substructures frequently observed in plastically deformed (PD) and additively manufactured (AM) metals and alloys, and the latter typically exhibit visible elemental segregation along the DC boundaries. This work comparatively analyzes the DC effects on the strain-hardening and strain-rate hardening capabilities of PD and AM austenitic stainless steels (ASSs). The findings suggest that the presence of Cr/Mo-decorated DCs contributes to superior yield strength and admirable mechanical stability for AM ASSs. However, the high critical stress required for deformation twinning leads to a decreased twinning ability, resulting in lower strain hardening capability for AM ASSs compared to PD counterparts. Additionally, micron-sized DCs significantly enhance the strain-rate hardening capability of the AM parts by reducing the dislocation-free path. The inherent DC substructure of these AM materials demonstrates promising energy-absorption performance under extreme-speed deformation conditions, particularly combined with intricate structural design advantages. © 2025 Elsevier B.V.

关键词： Austenitic stainless steel

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Determination of Elastoplastic Mechanical Properties of the Weld and Heat Affected Zone Metals in Tailor-Welded Blanks by Nanoindentation Test

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Chinese Journal of Mechanical Engineering 2015年第5期28卷 911-918页

作者： MA Xiangdong GUAN Yingping YANG Liu Key Laboratory of Advanced Forming & Stamping Technology and Science of Ministry of Education Yanshan University

The elastoplastic mechanical properties of the weld and heat affected zone metals have comparatively major impact on the forming process of tailor-welded blanks. A few scholars investigated the elastoplastic mechanical properties of the weld and heat affected zone, but they only simply assumed that it was a uniform distribution elastoplastic material different from the base materials. Four types of tailor-welded blanks which consist of ST12 and 304 stainless steel plates are selected as the research objects, the elastoplastic mechanical properties of the tailor-welded blanks weld and heat affected zone metals are obtained based on the nanoindentation tests, and the Erichsen cupping tests are conducted by combining numerical simulation with physical experiment. The nanoindentation tests results demonstrate that the elastoplastic mechanical properties of the weld and heat affected zone metals are not only different from the base materials, but also varying between the weld metals and the heat affected zone metals. Comparing the Erichsen cupping test resulted from numerical with that from experimental method, it is found that the numerical value of Erichsen cupping test which consider the elastoplastic mechanical properties of the weld and heat affected zone metals have a good agreement with the experimental result, and the relative error is only 4.8%. The proposed research provides good solutions for the inhomogeneous elastoplastic mechanical properties of the tailor-welded blanks weld and heat affected zone metals, and improves the control performance of tailor-welded blanks forming accuracy.

关键词： tailor-welded blanks elastoplastic mechanical properties nanoindentation test Erichsen cupping test

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Static Recrystallization Behavior of 316LN Austenitic Stainless Steel

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Journal of Iron and Steel Research International 2013年第11期20卷 67-72页

作者： JIN Miao LU Bo LIU Xin-gang GUO Huan JI Hai-peng GUO Bao-feng Key Laboratory of Advanced Forging and Stamping Technology and Science of Ministry of Education Yanshan University

The static recrystallization of 316LN austenitic stainless steel was studied by double-pass hot compression tests on a Gleeble 3500 thermomechanical simulator. The specimens were compressed at the deformation tempera- tures of 950, 1050, 1150 ℃, strain rates of 0.01, 0.1, 1 s^- 1, strains of 0.1, 0.15, 0.2, and intervals of 1-100 s. The results show that the volume fraction of static recrystallization of 316LN increases with the increase of deforma- tion temperature, strain rate, strain and interval, which indicates that static recrystallization occurs easily under the conditions of higher deformation temperature, higher strain rate and larger strain. Deformation temperature has sig- nificant influence on static recrystallization of 316LN. The volume fraction of static recrystallization could easily reach 1000% at higher deformation temperatures. By microstructure analysis, it can be concluded that the larger the volume fraction of static recrystallization, the more obvious the grain refinement. The static recrystallization activation energy of 317 882 J/mol and the exponent n of 0.46 were obtained. The static recrystallization kinetics was established. The predicted volume fraction of static recrystallization is in good agreement with the experimental results.

关键词： static recrystallization austenitic stainless steel hot deformation

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An Iterative Compensation Algorithm for Springback Control in Plane Deformation and Its Application

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Chinese Journal of Mechanical Engineering 2019年第2期32卷 212-223页

作者： Rui Ma Chunge Wang Ruixue Zhai Jun Zhao Key Laboratory of Advanced Forging & Stamping Technology and ScienceMinistry of Education of China Yanshan University College of Mechanical Engineering Yanshan University College of Mechanical and Energy Engineering Ningbo Institute of Technology Zhejiang University Key Laboratory of Roll Forming Technology Research

In order to solve the springback problem in sheet metal forming, the trial and error method is a widely used method in the factory, which is time-consuming and costly for its non-direction and non-quantitative. Finite element simulation is an e ective method to predict the springback of complex shape parts, but its precision is sensitive to the simulation model, particularly material model and boundary conditions. In this paper, the simple iterative method is introduced to establish the iterative compensation algorithm, and the convergence criterion of iterative parameters is put forward. In addition, the new algorithm is applied to the V-free bending and stretch-bending processes, and the convergence of curvature and bending angle is proved theoretically and verified experimentally. At the same time,the iterative compensation experiments for plane bending show that, the new method can predict the next compensaantido tnh ev atlaureg ebta cseurdv oatnu trhe ew sitphri tnhgeb earcrko ro fo fe laecshs ttehsat,n s0 o. 5 th%a ta rteh eo btatraigneet db aefntedri n2 g-3 a nitgelrea tiwoitnhs.t Thhei se rrreosre aorf clhe sps rtohpaons e±s 0 a.1%new iterative compensation algorithm to predict springback in sheet metal forming process, where each compensation value depends only on the iteration parameter di erence before and after springback for the same forming process of same material.

关键词： Springback control Iterative compensation algorithm Convergence criterion V-free bending Stretchbending

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