• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2018, Vol. 54 ›› Issue (18): 68-75.doi: 10.3901/JME.2018.18.068

• 材料科学与工程 • 上一篇    下一篇


康泽天, 周博, 薛世峰   

  1. 中国石油大学(华东)储运与建筑工程学院 青岛 266580
  • 收稿日期:2017-12-28 修回日期:2018-03-26 出版日期:2018-09-20 发布日期:2018-09-20
  • 通讯作者: 周博(通信作者),男,1972年出生,博士,教授,博士研究生导师。主要研究方向为智能材料与结构力学,油汽井工程力学,新能源工程力学,微尺度材料力学等。E-mail:zhoubo@upc.edu.cn
  • 基金资助:

Finite Element Numerical Simulation on Thermo-mechanical Coupling Behavior in Shape Memory Alloy Pipe Connection

KANG Zetian, ZHOU Bo, XUE Shifeng   

  1. College of Pipeline and Civil Engineering, China University of Petroleum, Qingdao 266580
  • Received:2017-12-28 Revised:2018-03-26 Online:2018-09-20 Published:2018-09-20

摘要: 为了克服形状记忆合金(Shape memory alloy,SMA)管接系统在装配过程中的数值模拟不够精细,SMA管接头紧固力影响因素研究不够详尽的缺点,基于热力学Gibbs自由能,推导SMA在相变过程中应力张量增量与马氏体体积分数增量之间的关系,基于非线性有限元分析软件ABAQUS二次开发功能,同时考虑材料弹性模量的变化以及马氏体相变的温度效应,编写ABAQUS用户材料子程序,对连接系统的装配过程进行数值模拟,有效描述整个管接系统在热力耦合作用下的相变和力学行为。数值结果表明,被连接管壁的应力最大值出现在内壁靠近管接头端口位置;管接头端口附近接触应力梯度很大,沿轴向从零迅速增加到最大值,然后逐渐回落到一个较高的稳定接触应力值;管接头管壁内的应力和马氏体相变沿管壁由内向外呈梯度分布;整体接触压应力水平表现出与管接头壁厚成正相关,与管接头内径成负相关,与扩径内压无关特性。更准确模拟了SMA管接系统在装配过程中的相变和力学行为,详尽分析了管接头产生紧固力的影响因素,为SMA管接头的设计提供理论基础和指导。

关键词: 本构方程, 管接头, 形状记忆合金, 有限元分析

Abstract: In order to overcome the disadvantages of the inexactness of the numerical simulation of shape memory alloy (SMA) pipe connection system and the abridgement of the research of influence factors on the fastening force of the SMA pipe connection during the total assemble process, based on the thermodynamic Gibbs free energy, the incremental relationship between the stress tensor and the martensitic volume fraction is derived and written in an ABAQUS user-defined material subroutine with considering the change of elastic modulus and the temperature effect of the martensite transition. The assemble process of the SMA pipe connection system is simulated and the phase transition and mechanical behavior of the whole pipe connection system subjected to thermo-mechanical coupling are described effectively. The numerical results indicate that the maximum stress of the connected pipe occurs at the inner wall near the pipe connection port. The contact pressure between the outer wall of the connected pipe and the inner wall of the SMA pipe connection has a large gradient near the port of the SMA pipe connection, which increases rapidly from zero to the maximum and then gradually falls back to a higher stable value along the axial direction. The stress and martensitic volume fraction all have a gradient distribution in the pipe connection wall from inward to outward. In addition, the contact pressure level shows a positive correlation with the thickness, which is negatively correlated with the inner diameter, and is not related to the internal loading pressure. The phase transition and mechanical behavior of the SMA pipe connection system are simulated more accurately, and the influence factors on the fastening force are analyzed in detail, which provides a theoretical basis and guidance for the design of the SMA pipe connection.[1]

Key words: constitutive equation, finite element analysis, pipe connection, shape memory alloy