自旋阀巨磁电阻位移传感器测金属线膨胀系数

Measuring Wire Expansion Coefficient Using Spin-Valve Giant Magnetoresistance Sensor

巨磁电阻在测量微弱磁场的变化较其他传感器具有体积小、灵敏度高等优点。比较了多层膜巨磁电阻和自旋阀巨磁电阻的区别,按其特性设计一个采用自旋阀巨磁电阻的位移传感器,并用此位移传感器精确测量金属的线膨胀系数。与各大高校在此实验中用普通方法测金属线膨胀系数的方法相比,该自旋阀巨磁电阻位移传感器测量金属线膨胀系数的方法有操作简便、测量精确,以及将力学量用电学量测量,并将物理数字化,便于电脑采集等优点。

Based on the comparison of multilayer giant magnetoresistance and spin-valve giant magnetoresistance and their characteristics,this article designed a displacement sensor with spin-valve giant magnetoresistance to measure the wire s linear expansion coefficient.Compared with the common method used in the experiment,this method using spin-valve giant magnetoresistance sensor to measure wire expansion coefficient has many advantages such as easy to operate,accurate to measure,transforming the value from mechanical into electrical for measurement, and digitalizing the physical value for computer acquisition.