Structural Design And Experimental Research Of Galfenol Force Sensor Based On Alternating Loads

As a new class of smart materials with piezomagnetic effect following the piezoelectric material and the GMM, Galfenol alloy which is found in the beginning of this century has good mechanical properties. It has tremendous advantages of welding, machine screw, large magnetostriction, small brittle, high tensile strength, low driving magnetic field, low hysteresis phenomenon and low cost etc.Force sensing technology is an important technology which is closely linked with people's daily life. With the development of modern advanced, sophisticated technology, accurate detection methods and testing methods is needed. Currently, the resistive force sensors, the piezoelectric force sensors and the giant magnetostrictive sensors have shortcomings. The resistive force sensors have the advantage of simple structure, but have the shortcomings of small linear working range and poor dynamic response; the piezoelectric force sensors cannot measure static and quasi-static stress; the endurances of giant magnetostrictive sensors are limited due to the brittleness of GMM. Galfenol alloy is a kind of material with both mechanical strength and magnetic magnetostriction, the shortcomings of traditional materials can be overcomed by the development of this alloy, a force sensor is proposed by using Galfenol alloy as the sensing component, in which the load can be measured continuously, even if the load changes with both direction and magnitude. The structure of force sensor is optimized by the finite element analysis based on the Galfenol force sensor. To provide theoretical supports and experimental data for further development, the building of test platform, the sample of force sensor, and experimental testing, were carried out in this dissertation. The main contents are as follows:The development process, the magnetostrictive material properties and the internal mechanism of Galfenol alloy is described. The application of Galfenol alloy at home and abroad is mainly introduced, meanwhile, the necessity of the structural design and experimental research of Galfenol force sensor based on the alternating loads is pointed on through a detailed analysis of the force sensors.To research on the magnetic properties of GMM and Galfenol alloy, a new test system,which can test the magnetic properties of magnetostrictive material, is designed. And the existing magnetic circuit structure is optimized through the finite element simulation analysis. On this basis, The research results show that Galfenol alloy is more suitable for the application and design of the sensor, GMM alloy is more suitable for large stroke, the application of high-power driven devices.On the basis of the working principle analysis of the the existing different new force sensor, A novel force sensor is proposed by using Galfenol alloy as the sensing component, in which the load can be measured continuously, a reasonable design structure parameters are obtained through theoretical calculation and finite element simulation analysis to make Galfenol alloy force sensor better effect.For the first time through the continuous synchronization acquisition of the experimental data test method, an experimental platform was established. The magnetization characteristics and the performance characteristics of the force sensor are studied through the experimental research to this type of sensor design has accumulated a large number of valuable experimental data, and to fill the gaps in the field of domestic experimental.