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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

Effects of Predeformation on the Reverse Martensitic Transformation of TiNi Shape Memory Alloy

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Journal of Materials Science & Technology 2000年第6期16卷 611-614页

作者： yanjun zheng lishan cui Fan ZHANG Dazhi YANG Department of Materials Science and Engineering University of Petroleum Beijing 102200 China Department of Materials Engineering Dalian University of Technology Dalian 116024 China

DSC was used to study the effects of predeformation on the reverse martensitic transformation of near-equiatomic TiNi alloy. Both the start temperature As and the finish temperature Af of the reverse transformation increased with increasing degree of predeformation, but the algebraic difference between As and Af decreased with increasing predeformation until it reached a minimum value, then remained unchanged with further deformation. Transformation heat also increased with increasing predeformation until it reached a maximum value, then decreased with further predeformation. All the phenomena above were considered to be closely related with the release of elastic strain energy during predeformation.

关键词： TiNi Effects of Predeformation on the Reverse Martensitic Transformation of TiNi Shape Memory Alloy

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

The Synthesis of TiNi and Composite Particles in Molten Salts

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Petroleum Science 2005年第3期2卷 37-39页

作者： Yang Ruisong cui lishan zheng yanjun Department of Materials Science and Engineering China University of Petroleum ChinaBeijing 102249

A novel process for synthesizing TiNi and TiNi/TiC particles, called the high-temperature salt-melting method, is discussed in this paper. So far as this method is concerned, the molten salts are a reaction medium that does not take part in the chemical reaction but can be easily dissolved by water washing. With this method, TiNi shape memory alloy and TiNi/TiC composite particles were prepared in molten salts at 680-850℃. TiNi particles, ranging from 100 nm to several microns in diameter, are obtained and the reverse martensitic transformation is confirmed in these particles by the differential scanning calorimetry （DSC）. The reaction temperature and the holding time have no significant influence on the particle size, morphology or the reverse martensitic transformation characteristics. In the molten salts, the released heat of the chemical reaction causes the local temperature to rise quickly, which is the key to obtaining the desired particulate composite.

关键词： TiC particles TiNi particles molten salts martensitic transformation

Ni_(50)Ti_(49)Nb_(1)合金的马氏体相变行为与超弹性

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功能材料 2024年第9期55卷 9172-9177页

作者：杨优奕李秋真崔立山于开元中国石油大学(北京)新能源与材料学院北京102249

通过室温拔丝与晶化退火工艺制得了不同晶粒尺寸的Ni_(50)Ti_(49)Nb_(1)和Ni_(50)Ti_(50)合金丝材。利用差示扫描量热仪(DSC)、电阻测试仪(ER)、X射线衍射仪(XRD)与透射电子显微镜(TEM)表征了样品的热致马氏体相变行为与微观组织结构,... 详细信息

通过室温拔丝与晶化退火工艺制得了不同晶粒尺寸的Ni_(50)Ti_(49)Nb_(1)和Ni_(50)Ti_(50)合金丝材。利用差示扫描量热仪(DSC)、电阻测试仪(ER)、X射线衍射仪(XRD)与透射电子显微镜(TEM)表征了样品的热致马氏体相变行为与微观组织结构,利用万能拉伸试验机测试了纳米晶样品在不同温度下的超弹特性。结果表明,两类合金的热致相变均随晶粒尺寸减小而愈发受制,当晶粒尺寸为纳米晶时,B19′相被完全抑制;低温时,纳米晶Ni_(50)Ti_(49)Nb_(1)样品R相受制更强。拉伸测试结果表明,纳米晶Ni_(50)Ti_(49)Nb_(1)样品在218~398 K温域内展现超弹性,显著优于纳米晶Ni_(50)Ti_(50)合金;前者相变临界应力以及应力滞后与温度呈非线性相关,与后者显著不同。研究结果有助于理解微量Nb掺杂对NiTi基合金相变行为与超弹性的影响规律,并为新型超弹合金设计提供思路。

关键词： NiTiNb合金相变行为超弹性 Nb掺杂

Mechanical Behaviors of TiNi Alloy under Dynamic Impact Loading Conditions

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Petroleum Science 2005年第3期2卷 40-43页

作者： Xu Renbo cui lishan zheng yanjun Chen Hongling Faculty of Mechanical and Electronic Engineering China University of Petroleum ChinaBeijing 102249

The mechanical behaviors of Ti-50.7%Ni shape memory alloy under a dynamic impact loading condition were investigated by a home-built impact testing system. Both the contact force and the contact time during the impact process were measured with a piezoelectric force sensor and a digital signal processing system in real time. The predicted instantaneous velocity and the displacement formulae are presented. Results show that the maximum contact force increased, while the contact time decreased with the increase of the temperature when the TiNi alloy was in a martensitic state. When the compressive stress during the impact process was higher than the critical stress of the stress-induced martensitic transformation, the TiNi alloy specimen in the parent phase left no permanent deformation but could dissipate the impact energy.

关键词： TiNi shape memory alloy contact force contact time impact energy

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