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Journal of Materials Science & Technology 2013年第9期29卷 863-867页

作者： Baicheng Zhang Jing Chen Christian Coddet LERMPS Université de Technologie de Belfort-Montbéliard Site de Sévenans Laboratoire des Matériaux Macromoléculaires Ingénierie des Matériaux Polymères

The selective laser melting （SLM） of Ti-Ni mixed powder with atomic ratio of 1：1 was performed in the present work in order to elaborate shape memory alloy （SMA）. The martensite phase of Ti-Ni alloy can be found by X-ray diffraction （XRD） analysis under temperature field, moreover, the Ti2Ni phase at a high scanning velocity. The crystalline phase images also show that the synthesized Ti-Ni alloy possessed a refined martensite microstructure. In order to evaluate the mechanical properties, the microhardness and porosity were measured. The microhardness is relatively high about 400HVo.2 with champ temperature. Besides, the porosity is quite low due to the excellent laser energy absorptivity and meltability of Ni element. The differential scanning calorimetry （DSC） analysis shows that the transformation temperature from austenite phase to martensite phase is relatively high and stable.

关键词： Selective laser melting Microstructnre shape memory alloy

An extended thermo-mechanically coupled algorithm for simulation of superelasticity and shape memory effect in shape memory alloys

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Frontiers of Structural and Civil Engineering 2015年第4期9卷 466-477页

作者： S. HASHEMI H. AHMADIAN S. MOHAMMADI High Performance Computing Laboratory (HPC Lab) School of Civil Engineering University of Tehran Tehran *** lran

Thermo-mechanical coupling in shape memory alloys is a very complicated phenomenon. The heat generation/absorption during forward/reverse transformation can lead to temperature-dependent variation of its mechanical behavior in the forms of superelasticity and shape memory effect. However, unlike the usual assumption, slow loading rate cannot guarantee an isothermal process. A two-dimensional thermo-mechanically coupled algorithm is proposed based on the original model of Lagoudas to efficiently model both superelasticity and shape memory effects and the influence of various strain rates, aspect ratios and boundary conditions. To implement the coupled model into a finite element code, a numerical staggered algorithm is employed. A number of simulations are performed to verify the proposed approach with available experimental and numerical data and to assess its efficiency in solving complex SMA problems.

关键词： shape memory alloy thermo-mechanical coupling superplasticity shape memory effect

Enhanced superelasticity of Cu-Al-Ni shape memory alloys with strong orientation prepared by horizontal continuous casting

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Frontiers of Materials Science 2022年第4期16卷 105-112页

作者： Mengwei WU Yu XIAO Zhuofan HU Ruiping LIU Chunmei MA Department of Materials Science and Engineering China University of Mining&Technology(Beijing)Beijing 100083China Institute for Advanced Materials and Technology University of Science and Technology BeijingBeijing 100083China

The preparation of large-scale Cu-Al-Ni shape memory alloys with excellent microstructure and texture is a significant challenge in this *** this study,large-scale Cu-Al-Ni shape memory alloy(SMA)slabs with good surface quality and strong orientation were prepared by the horizontal continuous casting(HCC).The microstructure and mechanical properties were compared with the ordinary casting(OC)Cu-Al-Ni *** results showed that the microstructure of OC Cu-Al-Ni alloy was equiaxed grains with randomly orientation,which had no obvious *** alloys producedby Hcchad herringbone grains withstrong orientation near(100)and the cumulative tensile superelasticity of 4.58%.The superelasticity of the alloy produced by HCC has been improved by 4-5 *** work has preliminarily realized the production of large-scale Cu-Al-Ni SMA slab with good superelasticity,which lays a foundation forexpanding the industrial production and application of Cu-based SMAs.

关键词： shape memory alloy Cu-Al-Ni orientation superelasticity

STUDY ON THE MAGNETISM AND PHASE TRANSFORMATIONIN Fe-Mn-Si-C shape memory alloyS

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Acta Metallurgica Sinica(English Letters) 1997年第3期10卷 219-223页

作者： Z.X Qinand Y.S. Zhang(Department of Materials Science and Engineering, Dalian Railway Institute, Dalian 116028, China) Dalian Railway Inst Dalian China

The hyperfine interactions of two shape memory alloys have been studied by Mossbauer effect measurement at various temperatures. The Mossbauer spectra exhibit a mag-netic change from antiferro magnetic state to paramagnetic state when the temperuture rises. The Fe-Mn-Si alloys have a small hyperfine field and silicon element increases the hyperfine field and magnetic susceptibility. Thermo-induced γ→ ε trunsforma-tions are suppressed by Neel transition and by increasing carbon content, whereas stress induced γ→ ε transformation occurs in both alloys. Antiferromagnetic spin order can suppress thermo-induced γ→εtransformations efficiently, but cannot sup-press stress induced γ → ε transformation.

关键词： phase transformation shape memory alloy magnetic susceptibility ε martensite

Martensitic transformation involved mechanical behaviors and wide hysteresis of NiTiNb shape memory alloys

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Progress in Natural Science:Materials International 2012年第2期22卷 130-138页

作者： Minjuan Wang a,b,Mingyang Jiang a,Guangyue Liao a,Shun Guo a,Xinqing Zhao a,a School of Materials Science and Engineering,Beihang University,Beijing 100191,China b Beijing Institute of Aeronautical Materials,Beijing 100095,China School of Materials Science and Engineering Beihang University Beijing 100191 China Beijing Institute of Aeronautical Materials Beijing 100095 China

On the basis of thermoelastic martensitic transformation involved,the mechanical behaviors of NiTiNb shape memory alloys were experimentally studied and their wide hysteresis effect was theoretically *** was found that even at the same temperature NiTiNb shape memory alloys perform different mechanical behaviors when under different *** addition,the yielding behavior for the reorientation of martensite is dependent on the martensitic transformation temperature of NiTiNb *** alloy with lower MS temperature exhibits lower yield stress for the reorientation of *** to kinetic and thermodynamic analysis of thermoelastic martensitic transformations,a relationship between the relaxation of elastic energy and the hysteresis expansion was *** is suggested that the mechanism for wide hysteresis of NiTiNb shape memory alloys is predominantly attributed to the Nb element dissolved in the matrix of NiTi(Nb)phase,rather than the precipitated b-Nb *** mechanism gains support from the present experimental study that the NiTiNb alloys with low Nb content exhibit wide transformation hysteresis upon a proper pre-deformation.

关键词： NiTiNb Martensitic transformation shape memory alloy Mechanical behavior Transformation hysteresis

Relationship between phase composition and corrosion resistance of Ni-Ti-Nb based shape memory alloys

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中国有色金属学报 2001年第Z1期11卷 118-120页

作者：董治中刘文西贾堤王德法 College of Materials Science and Engineering Tianjin University Tianjin Institute of Urban Construction

The stability and microstructure of Ni Ti Nb based shape memory alloys were investigated after alloyed with elements Zr, Cr and V. In artificial seawater (3.5%NaCl) and physiological solution (5%NaCl+0.1%H 2O 2), the results show that the alloying elements influence the corrosion behavior of Ni Ti Nb alloys. Generally, Zr improves the corrosion resistance of Ni Ti Nb alloy, Cr reduces its corrosion resistance and V does not change the property. In order to investigate the reason of the difference,the relation of the phase components and corrosion resistance of Ni Ti Nb based shape memory alloys were studied by element analysis and SEM.

关键词： Ni Ti Nb corrosion resistance phase components shape memory alloy

Temperature effects of shape memory alloys(SMAs)in damage control design of steel portal frames

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Frontiers of Structural and Civil Engineering 2012年第4期6卷 348-357页

作者： Xiaoqun LUO Hanbin GE Tsutomu USAMI Department of Building Engineering Tongji UniversityShanghai 200092China Department of Civil Engineering Meijo UniversityNagoya 468-8502Japa

The objective of the present study is to analytically investigate temperature effects of an axial-type seismic damper made of shape memory alloys(SMAs)equipped in steel *** on a modified multilinear one dimensional constitutive model of SMAs,two types of SMAs are employed,which have different stress plateau and different stress growth rate with temperature *** effects of SMA dampers on seismic performance upgrading are discussed in three aspects:different environment temperatures;rapid loading rate induced heat generation and different SMA *** analysis indicates that the effect of environment temperature should be considered for the SMA damper in steel ***,the rapid loading rate induced heat generation has little adverse effect.

关键词： damage control design shape memory alloy temperature effect

Effect of Two-times Annealing on Characteristics of TiNi Shapc-memory alloy

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Rare Metals 1994年第4期13卷 258-262页

作者：张金波孙序王福生何勇健

The thermo- induced and stress- induced transformations of a TiNi SMA after two times annealing werestudied by resistivity measurement and X-ray diffraction. The effect of heat treatment craft on characteristicsof SMA... 详细信息

关键词： shape memory alloy Thermo-induced transformation Stress-inducedtransformation M phase R phase B2 phase

Effects of Co and Al addition on martensitic transformation and microstructure in ZrCu-based shape memory alloys

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Transactions of Nonferrous Metals Society of China 2015年第3期25卷 850-855页

作者：高卫红孟祥龙蔡伟赵连城哈尔滨工业大学材料科学与工程学院哈尔滨150001

The effect of ternary alloying element Al and quaternary alloying element Co on the martensitic transformation of ZrCu-based shape memory alloy was investigated. The results show that the addition of Al and Co in ZrCu alloy decreases both the martensitic transformation temperature and the martensitic transformation temperature hysteresis. Transmission electron microscope (TEM) observations reveal that theCm martensite structure is the preferential formation phase. The intervariant structures in ZrCuAlCo alloy are (021) type I twins, while the dominant substructures inside the martensite variant are the (001) compound twins. With the increase of Co content, tensile fracture strength and strain are improved obviously.

关键词： ZrCu-based alloy shape memory alloy martensitic transformation microstructure

DEFORMATION OF CuZnAl shape memory alloyS IN MARTENSITIC STATE

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Acta Metallurgica Sinica(English Letters) 1989年第6期2卷 403-407页

作者： E.HORNBOGEN Institute for Materials Ruhr-University BochumF.R.G

Plastic deformation of three CuZnAl shape memory alloys in martensitic state was investi- gated by means of optical and electron metallography,dilatometry and electric resistiviy de- *** of the alloys are in martensitic state at ambient temperature,and the A_f temperature of the third one is far below the ambient *** effect of deformation of alloys in martensitic state on the course and temperature of transformation as well as the hysteresis of transformation cycles has been analyzed and the “effect of the first cycle” has also been discussed.

关键词： shape memory alloy deformation martensitic transformation