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Effects of Severe Plastic Deformation and Heat Treatment on Transformation Behavior of Explosively Welded Duplex TiNi-TiNi

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Petroleum Science 2007年第4期4卷 107-112页

作者： Li Juntao Zheng Yanjun cui lishan Department of Materials Science and Engineering China University of Petroleum Beijing 102249 China

The effects of severe plastic deformation and heat treatment on the transformation behavior of explosively welded duplex TiNi-TiNi shape memory alloys （SMAs） were investigated by differential scanning calorimeter （DSC） measurements. The explosively welded duplex TiNi-TiNi plate of 0.7 mm thickness was cold-rolled at room temperature to a 60% reduction in thickness and then annealed at different temperatures for different durations. The results showed that low temperature （623-723K） heat-treatment led to the crystallization of the amorphous region, and re-crystallization occurred in the specimens annealed at higher temperatures （over 873 K）. Research indicated that the change of martensitic transformation temperature is due to the change of internal stresses with increasing heat treatment temperature. The change of annealing time also led to a change in martensitic transformation temperature, which was associated with the precipitation and decomposition of Ti3Ni4 in TiNi-1.

关键词： TiNi explosive welding cold rolling martensitic transformation differential scanning calorimeter

Influence of Pseudoelasticity on Mechanical Behavior of TiNi Alloy under Dynamic Impact Loading

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Petroleum Science 2007年第1期4卷 86-89页

作者： Xu Renbo cui lishan Zheng Yanjun Chen Hongling Department of Materials Science and Engineering China University of Petroleum Beijing 102249 China

The mechanical behavior of TiNi alloy and Cr12MoV alloy under dynamic impact loading was investigated with a self-made impact testing system. The real-time contact force was measured with a piezoelectric force sensor and digital signal processing system during impact. Equations for predicting instantaneous velocity anti displacement were presented. The results showed that the TiNi alloy exhibited a plateau of maximum contact force with increasing impact height. At the plateau stage, TiNi alloy in the parent phase can absorb impact energy and keep the maximum contact force nearly identical due to its pseudoelasticity.

关键词： TiNi alloy mechanical behavior contact force impact energy pseudoelasticity

Properties of oxide films grown on 25Cr20Ni alloy in air-H_2O and H_2-H_2O atmospheres

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Petroleum Science 2014年第1期11卷 147-154页

作者： Wang Shenxiang cui lishan Wang Guoqing Zheng Yanjun Wang Hongxia Jia Jingsheng College of Science China University of Petroleum Beijing Research Institute of Chemical Industry

The oxidation kinetics,surface morphology and phase structure of oxide films grown on 25Cr20Ni alloy in air-H2O and H2-H2O atmospheres at 900 ℃ for 20 h were *** anti-coking performance and resistance to carburization of the two oxide films were compared using 25Cr20Ni alloy tubes with an inner diameter of 10 mm and a length of 850 mm in a bench scale naphtha steam pyrolysis *** oxidation kinetics followed a parabolic law in an air-H2O atmosphere and a logarithm law in a H2-H2O atmosphere in the steady-state *** oxide film grown in the air-H2O atmosphere had cracks where the elements Fe and Ni were enriched and the un-cracked area was covered with octahedral-shaped MnCr2O4 spinels and Cr1.3Fe0.7O3 oxide clusters,while the oxide film grown in the H2-H2O atmosphere was intact and completely covered with dense standing blade MnCr2O4 *** the pyrolysis tests,the anti-coking performance and resistance to carburization of the oxide film grown in the H2-H2O atmosphere were far better than that in the air-H2O *** mass of coke formed in the oxide film grown in the H2-H2O atmosphere was less than 10％ of that in the air-H2O *** Cr1.3Fe0.7O3 oxide clusters converted into Cr23C6 carbides and the cracks were filled with carbon in the oxide film grown in the air-H2O atmosphere after repeated coking and decoking tests,while the dense standing blade MnCr2O4 spinels remained unchanged in the oxide film grown in the H2-H2O *** ethylene,propylene and butadiene yields in the pyrolysis tests were almost the same for the two oxide films.

关键词： 25Cr20Ni alloy air-H2O H2-H2O oxide film anti-coking resistance to carburization

Oxidation of Fe-Cr-Ni Alloys in a Low Oxygen Partial Pressure Atmosphere to Mitigate Coke Formation

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China Petroleum Processing & Petrochemical Technology 2023年第3期25卷 49-59页

作者： Wang Hongxia Wang Guoqing Zhang Lijun Wang Shenxiang Jia Jingsheng cui lishan Sinopec(Beijing)Research Institute of Chemical Industry Co. Ltd.Beijing 100013China Departments of Materials Science and Engineering China University of PetroleumBeijing 102249China

Anti-coking oxide films were prepared on a 25Cr35Ni and 35Cr45Ni alloy surface under the low oxygen partialpressure atmosphere of a H2-H2O mixture. The composition and phase structure of the oxide films were analyzed by energydispersive spectroscopy (EDS), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS). The anti-cokingperformance of a mini tube made of a HP40 (25Cr35Ni) alloy was evaluated on a bench scale pyrolysis and coking test *** results showed that the surface Fe and Ni content decreased after the oxidation of the two alloys in a low oxygen partialpressure atmosphere. The oxide films were mainly composed of MnCr_(2)O_(4) and Cr_(2)O_(3). The average mass of coke in the minitube with oxide film decreased by 87% relative to that of a tube without an oxide film when the cracking temperature was 900℃. The ethylene, propylene, and butadiene yields in the pyrolysis tests were almost the same for the mini tubes withand without an oxide film. The oxide film on the alloy surface effectively inhibited catalytic filamentous coke *** industrial test showed that the run length of the cracking furnace with the in-situ coating technology was significantlyextended.

关键词： Fe-Cr-Ni alloy low oxygen partial pressure oxide film anti-coking ethylene cracking furnace in-situ coating

Large elastic strains and ductile necking of W nanowires embedded in TiNi matrix

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Journal of Materials Science & Technology 2021年第1期60卷 56-60页

作者： Daqiang Jiang Zhenghao Jia Hong Yang Yinong Liu Fangfeng Liu Xiaohua Jiang Yang Ren lishan cui Department of Materials Science and Engineering China University of Petroleum-BeijingBeijingChangping 102249China Department of Mechanical Engineering The University of Western AustraliaPerthWA 6009Australia Beijing Key Laboratory of Failure Corrosionand Protection of Oil/Gas FacilitiesChina University of Petroleum BeijingBeijing 102249China X-ray Science Division Argonne National LaboratoryLemontIL 60439USA

The deformation behaviors of W nanowires embedded in a TiNi matrix were investigated by means of in-situ synchrotron high energy X-ray diffraction(HEXRD) and in-situ transmission electron microscopy(TEM) analysis during tensile *** HEXRD measurement indicated that the W nanowires exhibited an average lattice strain of about 1.50 %,whereas the TEM examination revealed a local elastic strain of about 4.59 % in areas adjacent to the TiNi matrix where stress-induced martensitic transfo rmation *** strain corresponds to a stress of ~15 GPa for the W *** addition,in areas adjacent to the TiNi matrix where plastic deformation and cracking were generated,the W nanowire showed significant ductile necking with ~80 % reduction in cross-section *** ductile necking of W nanowire is attributed to the lack of protection from the stress-induced martensitic transformation of the TiNi matrix.

关键词： Tungsten Nanowire In-situ TEM Elastic strain

Selective laser melting of NiTi alloy with superior tensile property and shape memory effect

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Journal of Materials Science & Technology 2019年第10期35卷 2238-2242页

作者： Zhiwei Xiong Zhonghan Li Zhen Sun Shijie Hao Ying Yang Meng Li Changhui Song Ping Qiu lishan cui State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyBeijing100094China School of Mechanical&Automotive Engineering South China University of TechnologyGuangzhou510641China

It is a challenge to develop complex-shaped Ni Ti shape memory alloy parts by traditional processing methods, due to the poor machinability of Ni Ti alloy. It is reported that selective laser melting(SLM) of additive manufacturing could overcome this problem. However, the reported SLM-produced Ni Ti exhibits poor tensile ductility due to the inner defects and adverse unidirectional columnar grains from SLM process. In this work, the defect-less SLM-Ni Ti with nondirective columnar grains was fabricated by optimizing the intraformational laser scanning length and interformational laser scanning direction. The obtained lath-shaped SLM-Ni Ti sample exhibits tensile strain of 15.6%, more than twice of the reported maximum result(7%). Besides, the SLM-Ni Ti part with complex geometry displays a shape memory recovery of 99% under compressive deformation of 50%.

关键词： NiTi shape memory alloy Selective laser melting Tensile ductility Shape memory effect

Grain-size gradient NiTi ribbons with multiple-step shape transition prepared by melt-spinning

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Journal of Materials Science & Technology 2021年第12期71卷 163-168页

作者： Xiangguang Kong Ying Yang Shiyu Guo Ran Li Bo Feng Daqiang Jiang Meng Li Changfeng Chen lishan cui Shijie Hao State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing102249China Beijing Key Laboratory of Failure Corrosionand Protection of Oil/Gas FacilitiesChina University of Petroleum BeijingBeijing102249China Key Laboratory of Aerospace Materials and Performance School of Materials Science and EngineeringBeihang UniversityBeijing100191China Qian Xuesen Laboratory of Space Technology China Academy of Space TechnologyYouyi Street No.104HaidianBeijing100094China

A grain-size gradient Ni Ti ribbon with multiple-step shape transition was papered by means of *** ribbons contain coarse and fine grains in the free surface side and copper roller surface side,*** grain-size gradient microstructure induces a two-stage phase transformation behavior in the ribbons during heating or *** tensile deformation pre-treatment,the ribbons exhibit a back-and-forth shape change(shape A→B→A)upon a single heating or cooling process,resulting from the sequential phase transformation through the thickness of the ribbon as dictated by gradient grain *** activating performance of the ribbons,*** transition amplitude and speed,can be customized by controlling the pre-deformation *** work offers a new opportunity for innovative designs to reach a novel shape memory behavior in Ni Ti alloys conveniently and efficiently.

关键词： NiTi shape memory alloy Melt spinning Shape memory effect Martensitic transformation

Exploiting ultra-large linear elasticity over a wide temperature range in nanocrystalline NiTi alloy

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Journal of Materials Science & Technology 2020年第22期54卷 197-203页

作者： Zhen Sun Shijie Hao Genfa Kang Yang Ren Junpeng Liu Ying Yang Xiangguang Kong Bo Feng Cheng Wang Kun Zhao lishan cui State Key Laboratory of Heavy Oil Processing China University of PetroleumBeijing 102249China Beijing Key Laboratory of Failure Corrosionand Protection of Oil/Gas FacilitiesChina University of Petroleum BeijingBeijing 102249China X-ray Science Division Argonne National LaboratoryArgonneIL 60439USA State Key Laboratory of Nonlinear Mechanics Institute of MechanicsChinese Academy of SciencesBeijing 100190China

Many shape memory alloys can support large recoverable strains of a few percent by reversible stressinduced martensite transformation,yet they behave non-linear within a narrow operating temperature ra *** the bulk metallic materials with ultra-large linear elasticity over a wide tempe rature range has proven to be *** this work,a material design concept was proposed,that is true elastic deformation and reversible twinning-detwinning deformation run in parallel to overcome this challe *** engineering the residual internal stress to realize the concurrency of true elastic deformation and twinning-detwinning deformation,a bulk nanocrystalline NiTi that possesses an ultra-large linear elastic strain up to 5.1 % and a high yield stress of 2.16 GPa over a wide temperature range of 270℃ was *** study offers a new avenue for developing the metallic materials with ultra-large linear elasticity over a wide temperature range of 270℃(from 70℃ to-197℃).

关键词： NiTi Nanocrystalline Linear-elasticity Wide temperature range Twinning

Two-stage Strain Recovery of Explosively Welded NiTi/NiTi Shape Memory Alloys Prestrained in Martensitic Phase

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Petroleum Science 2006年第3期3卷 86-89页

作者： Yan Zhu cui lishan Zheng Yanjun Department of Materials Science and Engineering China University of Petroleum Beijing 102249 China

The present work aimed to investigate the transformation behavior and strain recovery characteristics of Ni50.2Ti/Ni51Ti shape memory alloys （SMAs） prepared by explosive welding. The differential scanning calorimetry （DSC） results showed that the reverse transformation temperatures and the temperature range of NiTi-NiTi alloys increased with increasing prestrain level. Meanwhile, a two-stage strain recovery over a wide temperature range was obtained.

关键词： Explosive welding martensitic transformation strain recovery