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Transactions of Nonferrous Metals Society of China 2021年第5期31卷 1381-1396页

作者： Yan-qiu ZHANG shu-yong jiang College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China

Based on molecular dynamics(MD)simulation,the mechanisms of plastic anisotropy in nanotwinned polycrystalline copper with{111}texture during tensile deformation were systematically studied from the aspects of Schmid factor of the dominant slip system and the dislocation *** results show that the Schmid factor of dominated slip system is altered by changing the inclining angle of the twin boundaries(TBs),while the yield stress or flow stress does not strictly follow the Schmid *** exist hard and soft orientations involving different dislocation mechanisms during the tensile *** strengthening mechanism of hard orientation lies in the fact that there exist interactions between the dislocations and the TBs during plastic deformation,which leads to the dislocation blocking and *** softening mechanism of soft orientation lies in the fact that there is no interaction between the dislocations and the TBs because only the slip systems parallel to the TBs are activated and the dislocations slip on the planes parallel to the *** is concluded that the plastic anisotropy in the nanotwinned polycrystalline copper with{111}texture is aroused by the combination effect of the Schmid factor of dominated slip system and the dislocation mechanism.

关键词： mechanical property dislocations molecular dynamics plastic anisotropy nanotwins

Influence of Fe Addition on Phase Transformation,Microstructure and Mechanical Property of Equiatomic NiTi Shape Memory Alloy

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Acta Metallurgica Sinica(English Letters) 2017年第8期30卷 762-770页

作者： Ya-Nan Zhao shu-yong jiang Yan-Qiu Zhang Yu-Long Liang College of Mechanical and Electrical Engineering Harbin Engineering University Harbin 150001 China College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 China

Based on equiatomic nickel and titanium, three kinds of NiTiFe alloys with a nominal chemical composition of Ni49Ti49Fe2, Ni48Ti48Fe4 and Ni47Ti47Fe6 （at.%）, respectively, have been designed to investigate the influence of the addition of Fe element on phase transformation, microstructure and mechanical property of equiatomic NiTi shape memory alloy. The microstructures of three kinds of NiTiFe alloys are characterized by the equiaxed grains instead of the dendrites. Consequently, some Ti2Ni precipitates are found to distribute in the grains interior and at the grain boundaries. The content of Fe element has an important influence on mechanical property of NiTiFe alloy. With increasing content of Fe element, the strength of NiTiFe alloy increases substantially, but the plasticity decreases sharply. It can be concluded that pre- cipitation strengthening and solution strengthening play a significant role in enhancing the strength of NiTiFe alloy. In the case of three NiTiFe alloys, neither martensitic transformation nor reverse transformation can be observed in the range from -150 to 150 ~C. On the one hand, the phase transformation temperature is probably out of the scope of the present experimental temperature. On the other hand, the addition of Fe element probably suppresses first-order martensitic transformation or reverse transformation, and consequently the second-order-like phase transformation from an incom- mensurate stage to a commensurate stage can probably take place.

关键词： Shape memory alloy Mechanical property Microstructure Phase transformation

Prediction of grain scale plasticity of NiTi shape memory alloy based on crystal plasticity finite element method

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Transactions of Nonferrous Metals Society of China 2019年第4期29卷 775-784页

作者： Li HU shu-yong jiang Lai-xin SHI Yan-qiu ZHANG College of Material Science and Engineering Chongqing University of TechnologyChongqing 400054China College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China

Grain scale plasticity of NiTi shape memory alloy(SMA)during uniaxial compression deformation at 400℃was investigated through two-dimensional crystal plasticity finite element simulation and corresponding analysis based on the obtained orientation *** and strain distributions of the deformed NiTi SMA samples confirm that there exhibits a heterogeneous plastic deformation at grain *** stored dislocation(SSD)density and geometrically necessary dislocation(GND)density were further used in order to illuminate the microstructure evolution during uniaxial *** is responsible for sustaining plastic deformation and it increases along with the increase of plastic *** plays an important role in accommodating compatible deformation between individual grains and thus it is correlated with the misorientation between neighboring grains,namely,a high GND density corresponds to large misorientation between grains and a low GND density corresponds to small misorientation between grains.

关键词： grain scale plasticity NiTi shape memory alloy crystal plasticity finite element method plastic deformation microstructure evolution

Stress-induced martensite phase transformation of FeMnSiCrNi shape memory alloy subjected to mechanical vibrating polishing

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Transactions of Nonferrous Metals Society of China 2020年第6期30卷 1582-1593页

作者： shu-yong jiang Yu WANG Xiao-dong XING Yan-qiu ZHANG College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China College of Materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001China

Fe66Mn15Si5Cr9Ni5(wt.%)shape memory alloy(SMA)withγaustenite andεmartensite was subjected to mechanical vibrating polishing and consequently its surface suffered from plastic deformation in the case of compressive *** completeεmartensite transformation is found to occur in FeMnSiCrNi sample subjected to mechanical vibrating polishing,where stress-induced martensite transformation plays a predominant *** martensite transformation of FeMnSiCrNi SMA is closely related to the orientation of external *** complicated compressive stress which results from the mechanical vibrating polishing contributes toεmartensite transformation fromγaustenite of FeMnSiCrNi *** vibrating polishing has a certain influence on the surface texture ofεmartensite of FeMnSiCrNi SMA,where■texture appears in the polished FeMnSiCrNi SMA.

关键词： shape memory alloy mechanical polishing martensitic transformation texture microstructure

Mechanically-induced martensite transformation of NiTiFe shape memory alloy subjected to plane strain compression

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Transactions of Nonferrous Metals Society of China 2020年第5期30卷 1325-1334页

作者： shu-yong jiang Jun-bo YU Yan-qiu ZHANG Xiao-dong XING College of Mechanical and Electrical Engineering Harbin Engineering UniversityHarbin 150001China College of Materials Science and Chemical Engineering Harbin Engineering UniversityHarbin 150001China

Based on the channel die compression, NiTiFe shape memory alloy(SMA) was subjected to plane strain compression. Mechanically-induced martensite transformation, nanocrystalline and amorphous phase can be observed in the case of large plastic strain. Mechanically-induced martensite transformation is obviously different from the conventional stress-induced martensite transformation. The former generally occurs after dislocation slip, whereas the latter arises prior to dislocation slip. The occurrence of B19’ martensite phase contributes to accommodating subsequent plastic deformation of NiTiFe SMA. Mechanically-induced B19’ martensite is partially stabilized due to the existence of local high stress field and consequently it is unable to be reverted to B2 austenite phase during unloading.

关键词： shape memory alloy NiTiFe alloy plastic deformation martensitic transformation microstructure

Constitutive equation and processing map of equiatomic NiTi shape memory alloy under hot plastic deformation

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Transactions of Nonferrous Metals Society of China 2016年第8期26卷 2152-2161页

作者： Yan-qiu ZHANG shu-yong jiang Ya-nan ZHAO Si-wei LIU School of Mechanical and Electrical Engineering Harbin Engineering University Harbin 150001 China Hubei Water Resources Research Institute Wuhan 430070 China

In order to describe the deformation behavior and the hot workability of equiatomic NiTi shape memory alloy (SMA) during hot deformation, Arrhenius-type constitutive equation and hot processing map of the alloy were developed by hot compression tests at temperatures ranging from 500 to 1100 °C and strain rates ranging from 0.0005 to 0.5 s?1. The results show that the instability region of the hot processing map increases with the increase of deformation extent. The instability occurs in the low and high temperature regions. The instability region presents the adiabatic shear bands at low temperatures, but it exhibits the abnormal growth of the grains at high temperatures. Consequently, it is necessary to avoid processing the equiatomic NiTi SMA in these regions. It is preferable to process the NiTi SMA at the temperatures ranging from 750 to 900 °C.

关键词： NiTi alloy shape memory alloy hot plastic deformation constitutive equation hot processing map

Hepatic cystic lesions mimicking liver abscess on imaging: A report oftwo cases

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Hepatobiliary & Pancreatic Diseases International 2024年第1期23卷 86-89页

作者： Yun-Wen jiang yong-Hong Yu Tian-An jiang shu-Yuan Tian Department of Ultrasound Medicine Tongde Hospital of Zhejiang ProvinceHangzhou 310012China Department of Ultrasound Medicine the First Affiliated HospitalZhejiang University School of MedicineHangzhou 310003China

Hepatic cystic lesions include congenital dysplasia,inflammatory cystic lesions,neoplastic cystic lesions and parasitic cystic *** different treatment modalities can be chosen for these lesions,differential diagnosis is particularly important[1].Clinical features or imaging findings of cystic lesions of the liver are typical;for instance,liver abscess often shows thick-walled enhancement on contrast-enhanced CT.

关键词： lesions Hepatic cystic

Influence of Fe addition on phase transformation behavior of Ni Ti shape memory alloy

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Transactions of Nonferrous Metals Society of China 2017年第7期27卷 1580-1587页

作者： Yan-qiu ZHANG shu-yong jiang Xiao-ming ZHU Ya-nan ZHAO Yu-long LIANG Dong SUN College of Mechanical and Electrical Engineering Harbin Engineering University Harbin 150001 China College of Materials Science and Chemical Engineering Harbin Engineering University Harbin 150001 China

Three different NiTi-based alloys,whose nominal compositions were Ni50Ti50,Ni49Ti49Fe2,Ni45Ti51.8Fe3.2(molefraction,%),respectively,were used in the current research to understand the influence of Fe addition on phase transformationbehavior in NiTi shape memory alloy(SMA).The microstructure and phase transformation behavior of the alloys were investigatedby optical microscopy(OM),transmission electron microscopy(TEM),X-ray diffraction(XRD)and differential scanningcalorimetry(DSC)*** results show that the matrix of the Ni50Ti50alloy consists of both B19′(martensite)phase and B2(austenite)***,the substructures of twins could be observed in the B19′***,the ternary alloys of NiTiFeexhibit B2phase in the *** microstructures were also characterized by large presence of Ti2Ni precipitatesdispersed homogenously in the matrix of the two kinds of *** addition of Fe to the NiTi SMA results in the decrease in phasetransformation temperatures in the ternary *** on mechanism analysis,it can be concluded that this phenomenon isprimarily attributed to atom relaxation of the distorted lattice induced by Ni-antisite defects and Fe substitutions during phasetransformation,which enables stabilization of B2phase during phase transformation.

关键词： shape memory alloy NiTi alloy NiTiFe alloy microstructure austenite martensite

Aero-Hydro-Elastic-Servo Modeling and Dynamic Response Analysis of A Monopile Offshore Wind Turbine Under Different Operating Scenarios

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China Ocean Engineering 2024年第3期38卷 379-393页

作者： XIE shuang-yi GAO Jian LI yong-ran jiang shu-xin ZHANG Cheng-lin HE Jiao College of Mechanical Engineering Chongqing University of TechnologyChongqing 400044China Beijing Institute of Precision Mechatronics and Controls Beijing 100076China College of Mechanical and Vehicle Engineering Chongqing UniversityChongqing 400044China Fishery Machinery and Instrument Research Institute Chinese Academy of Fishery SciencesShanghai 200092China School of Mechanical and Power Engineering Chongqing University of Science&TechnologyChongqing 401331China

This paper constructs a coupled aero-hydro-elastic-servo simulation framework for a monopile offshore wind turbine(OWT).In this framework,a detailed multi-body dynamics model of the monopile OWT including the gearbox,blades,tower and other components(nacelle,hub,bedplate,etc.)has been explicitly *** effects of pile−soil interaction,controller and operational conditions on the turbine dynamic responses are studied systematically in time domain and frequency *** results show that(1)a comprehensive drivetrain model has the capability to provide a more precise representation of the complex dynamic characteristics exhibited by drivetrain components,which can be used as the basis for further study on the dynamic characteristics of the drivetrain.(2)The pile−soil interaction can influence the wind turbine dynamic responses,particularly under the parked condition.(3)The effect of the pile−soil interaction on tower responses is more significant than that on blade responses.(4)The use of the controller can substantially affect the rotor characteristics,which in turn influences the turbine dynamic responses.(5)The tower and blade displacements under the operational condition are much larger than those under the parked *** model and methodology presented in this study demonstrate potential for examining complex dynamic behaviors of the monopile *** ensure accuracy and precision,it is imperative to construct a detailed model of the wind turbine system,while also taking into account simulation efficiency.

关键词： offshore wind turbine(OWT) pile−soil interaction dynamic response parked condition operating condition

Dynamic recovery and dynamic recrystallization of NiTi shape memory alloy under hot compression deformation

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Transactions of Nonferrous Metals Society of China 2013年第1期23卷 140-147页

作者：江树勇张艳秋赵亚楠哈尔滨工程大学工程训练中心哈尔滨150001

Mechanical behavior of nickel？titanium shape memory alloy（NiTi SMA） under hot deformation was investigated according to the true stress—strain curves of NiTi samples under compression at the strain rates of 0.001-1 s-1 and at the temperatures of 600？1000℃.Dynamic recovery and dynamic recrystallization of NiTi SMA were systematically investigated by microstructural *** influence of the strain rates,the deformation temperatures and the deformation degree on the dynamic recovery and dynamic recrystallization of NiTi SMA was obtained as *** SMA was characterized by the combination of dynamic recovery and dynamic recrystallization at 600℃ and 700℃,but the complete dynamic recrystallization occurred at other deformation *** the deformation temperatures or decreasing the stain rates leads to larger equiaxed *** deformation degree has an important influence on the dynamic recrystallization of NiTi *** exists the critical deformation degree during the dynamic recrystallization of NiTi SMA,beyond which the larger deformation degree contributes to obtaining the finer equiaxed grains.

关键词： NiTi alloy shape memory alloy dynamic recovery dynamic recrystallization hot deformation