温度对铁基形状记忆合金回复应力与力学性能的影响
Effect of temperature on recovery stresses and properties of iron-based shape memory alloys
张耀文 1陈适才 1孔潇 1戎树伟 2王经臣2
作者信息
- 1. 北京工业大学城市建设学部,北京 100124
- 2. 中铁建设集团有限公司,北京 100049
- 折叠
摘要
为研究温度对铁基形状记忆合金(Fe-SMA)回复应力的影响与力学特性,开展了 Fe-SMA温度相关力学性能实验及其影响规律研究.首先,通过预拉伸、激活实验研究了不同激活温度对Fe-SMA棒材回复应力的影响规律,并在实验研究的基础上,建立了 Fe-SMA回复应力-温度的经验本构模型;其次,进行二次加热实验研究了不同激活温度、附加荷载和暴露温度对Fe-SMA棒材回复应力的影响;最后,通过高温后的Fe-SMA棒材单调拉伸实验,研究其高温后的力学性能.研究结果表明,建立的Fe-SMA回复应力-温度的模型,可以有效地模拟Fe-SMA的回复应力与温度的关系;在二次加热过程中,当激活温度低于200 ℃时,Fe-SMA具有较高的应力保持比.Fe-SMA棒材的应力损失随着附加荷载和暴露温度的增加有所增大;在经历高温后,剩余的形状记忆效应使得Fe-SMA棒材的应力高于初始应力,并且其弹性模量和极限强度保持相对稳定,而屈服强度随着暴露温度的升高而略微增加.该研究可为Fe-SMA构件的抗火设计与应用提供参考依据.
Abstract
In order to study the effect of temperature on the recovery stress and mechanical properties of iron-based shape memory alloys(Fe-SMA),experiments on the temperature-related mechanical properties of Fe-SMA and their influence laws were carried out.Firstly,the effects of different activation temperatures on the recovery stress of Fe-SMA rods were investigated by pre-stretching and activation experiments,and an empiri-cal ontological model of recovery stress-temperature of Fe-SMA was established on the basis of experimental studies.Secondly,secondary heating experiments were carried out to investigate the effects of different activa-tion temperatures,additional loads,and exposure temperatures on the recovery stress of Fe-SMA rods.Finally,the mechanical properties of Fe-SMA rods after high temperature were investigated by monotonic tensile experi-ments.The results show that the established model of Fe-SMA recovery stress-temperature can effectively sim-ulate the relationship between recovery stress and temperature of Fe-SMA.During the secondary heating process,when the activation temperature is lower than 200 ℃,Fe-SMA has a high stress retention ratio,and the stress loss of Fe-SMA rods increases with the elevated of the additional load and the exposure temperature.After experiencing high temperature,the residual shape memory effect induces higher stresses in Fe-SMA rods compared to the initial stresses.The modulus of elasticity and ultimate strength exhibit relative stability,whereas the yield strength experiences a slight increase with rising exposure temperatures.This investigation serves as a reference for informing the fire-resistant design and utilization of Fe-SMA members in academic dis-course.
关键词
形状记忆合金(SMA)/形状记忆效应/温度作用/回复应力/力学性能Key words
shape memory alloy(SMA)/shape memory effect/temperature effect/recovery stress/mechanical properties引用本文复制引用
出版年
2024
NETL
NSTL
万方数据