Research On Heterojunction Magnetoelectric Composite Material And Magnetoelectric Weak Magnetic Sensor

The polarization strength of materials changes with the change of the external magnetic field or vice versa.Materials with this effect are called magnetoelectric materials.This material can achieve the conversion between magnetic signals and telecommunications.It can be detected by measuring the electrical quantity.Indirect detection of magnetic field signals has important applications in many fields,such as scientific research(observation and monitoring of formation movement,cosmic microwave measurement),national defence(monitoring of moving targets,antisubmarine and anti-frogman operations),and medical fields(like heart magnetic & brain magnetic imaging).Since Dzyaloshinskii.Astrov first observed the magnetoelectric effect on a Cr2O3 single crystal in 1961,single-phase magnetoelectric materials have not developed significantly after nearly half a century of development,and are still far from concrete engineering applications.A certain distance,but if the composite magnetoelectric material obtained by combining the two phases of the magnetostrictive material and the piezoelectric material can achieve very strong magnetoelectric properties at room temperature,this property makes the magnetoelectric material large-scale engineering applications possible.The magnetoelectric sensors described herein refer to a type of magnetic sensor that uses a composite magnetoelectric material as a magnetoelectric conversion unit(sensitive element).It is a magnetoelectric sensor based on Metglas/Mn-PMNT.At present,it can compete with other high-performance magnetic sensors in terms of detection capability,and the magnetoelectric sensor has certain advantages in other comprehensive performance.The main work of this paper is to develop a highperformance magnetoelectric sensor based on Metglas/Mn-PMNT(magnetostrictive material/piezoelectric material),while optimizing the existing structure and components,further improving the sensor performance and striving to achieve the magnetoelectricity sensors engineering applications.In this paper,the preparation and characterization of composite magnetoelectric materials,qualitative analysis,and quantitative experiments were performed to verify the effect of the thickness of the adhesive layer on the Q value of the magnetoelectric composite materials.Based on the magnetic convergence effect and the principle of the magnetic circuit,a new bulk composite was designed.Structure,increasing the magnetoelectric coefficient of the magnetoelectric composite material by 51.4%(max value);theoretical analysis and experimental verification,finally solving the problems of saturation and zero drift of the precharge amplifier of the magnetoelectric sensor;besides,for the engineering application of the magnetoelectric sensor,the design is stable and easy to use Package structure,theoretical analysis and design of underwater comparison experiments and experimental schemes for shallow sea navigation.Compared with the high-performance magnetic sensors(flux gates,superconducting quantum interferometers,etc.)commonly used in the market,the new principle magnetoelectric sensors researched and produced in this paper have lower noise,smaller power consumption,smaller size and lower cost.Advantages,in some application scenarios,it is possible to replace traditional high-performance magnetic sensors,and in the current international environment,independent research and development,100% domestically produced magnetoelectric field-weak magnetic sensors have greater application prospects and economic value.