电热形状记忆合金与磁流变联合传动性能研究

针对单一的磁流变传动传递转矩较小的缺点,提出了一种电热形状记忆合金与磁流变联合传动方法,可以提高传动装置传递的转矩。基于形状记忆合金的热效应特性,建立了电热形状记忆合金弹簧挤压力与温度的关系;利用Maxwell软件,对磁场进行有限元分析,得到了不同电流下圆盘工作间隙中的磁场强度沿半径的分布情况;基于磁流变液的磁流变特性,建立了磁流变传递的转矩与磁场强度、半径等参数的关系;基于形状记忆合金弹簧的挤压特性,建立了摩擦转矩与挤压力、半径等参数的关系式。研究结果表明,电热形状记忆合金弹簧的挤压力产生的摩擦转矩随温度的升高而增大;磁场强度沿半径的增大而增强;电热形状记忆合金与磁流变联合传递的转矩比单一磁流变传递的转矩提升了53.8%。

Study on the Performance of Electrothermal Shape Memory Alloy and Magnetorheological Combined Drive

In order to overcome the disadvantage of small transfer torque in single magnetorheological drive,a combined drive method of electrothermal shape memory alloy(SMA)and magnetorheological is pro?posed,which can improve the transfer torque of drive device.Based on the thermal effect characteristics of shape memory alloy,the relationship between extrusion force and temperature of electrothermal SMA spring is established.Maxwell software is used to carry out finite element analysis of the magnetic field and obtain the dis?tribution of the magnetic field intensity along the radius in the working gap of the disc under different currents.Based on the magnetorheological characteristic of magnetorheological fluids,the relationship between the torque transferred by magnetorheological fluids and the parameters such as magnetic field strength and radius is established.Based on the extrusion characteristics of SMA springs,the relationship between friction torque and extrusion force,radius and other parameters is established.The results show that,the friction torque produced by the extrusion force of the electrothermal shape memory alloy spring increases with the temperature increas?ing.The magnetic field increases with increasing radius.The combined transfer torque of the electrothermal shape memory alloy and magnetorheological(MR)is 53.8%higher than that of a single MR transmission.