CAJ | 학술논문

利用形状记忆因子的概念,建立了用于描述纯剪切状态下形状记忆合金(SMA)相变行为的形状记忆演化方程.在假设SMA为各向同性材料和利用三维细观力学本构方程的前提下,推导了纯剪切状态下SMA的力学本构方程.所建立的形状记忆演化方程和力学本构方程中的材料常数均可以通过宏观实验来测定,便于工程实际中的应用.数值计算结果表明,所建立的形状记忆演化方程能正确地描述纯剪切状态下SMA发生在奥氏体、孪晶马氏体和非挛晶马氏体间的相变行为,力学本构方程可再现形状记忆效应和超弹性的热力学过程.
이용형상기억인자적개념,건립료용우묘술순전절상태하형상기억합금(SMA)상변행위적형상기억연화방정.재가설SMA위각향동성재료화이용삼유세관역학본구방정적전제하,추도료순전절상태하SMA적역학본구방정.소건립적형상기억연화방정화역학본구방정중적재료상수균가이통과굉관실험래측정,편우공정실제중적응용.수치계산결과표명,소건립적형상기억연화방정능정학지묘술순전절상태하SMA발생재오씨체、련정마씨체화비련정마씨체간적상변행위,역학본구방정가재현형상기억효응화초탄성적열역학과정.
It is of engineering interest to establish a constitutive model which includes the equa-tions describing the phase transformation and mechanical behaviors of shape memory alloys (SMA) in pure shear state. In this study, such a shape memory evolution equation is established using the shape memory factor and Brinson's relationship of phase transformation critical stress and temper-ature. A mechanical constitutive equation is also developed from 3D micro-mechanical constitutive equation based on the assumption that SMA is isotropic material to express the mechanical behaviors of SMA in pure shear state. All material constants in the shape memory evolution equation and me-chanical constitutive equation can be determined through macroscopic experiments, so that they are more easily used in practical applications. Numerical simulation results show that this shape memory evolution equation could simulate truly the processes of phase transformations in austenite, twinned and detwinned martensites, and the mechanical constitutive equation could predict reasonably the mechanical behaviors of SMA in pure shear state.