Research On The Magnetic Measurement System Based On Diamond Anvil Cell

With the rapid development of modern science and technology, the researchers were not satisfied with the research of the existing materials, began to explore the material under the extreme conditions, wanted to discover the material changes of the nature and the structure.And stress is one of the important means of studying the matter, the structure and properties of the materials may change when there is high temperature and pressure,the research on this kind of extreme conditions has greatly promoted the development of other fields.such as geology and material science.Because of the advantages of static high voltage technology in stability,controllability and other aspects, the research of the material under high pressure can provide a great help, while the static pressure technology in diamond on top of the anvil apparatus has greatly promoted the development of high pressure science.Due to the nature of diamond in optical, thermal, electrical,diamond anvil cell can be connected with other related equipment to carry out the experiment, and makes it more convenient to observe the experiment and the data.Magnetism is one of the properties of all the substances in nature, but the degree of magnetism will be different, so the study of magnetism has been a frontier subject.And the ferromagnetic is very typical of the magnetic, and the iron under pressure will have a phase transition, the phase transition may change the nature of the material,and for the study of the magnetic properties of some of the earth’s crust is of great help.Therefore, the study of ferromagnetic materials has been very important.At present, under the high pressure, the magnetic measurement of the material has been developed, the researchers have invented the diamond anvil cell technology for the iron magnetic material pressure, under the fixed pressure with the change ofthe temperature of the research.0In the experiment, we try to make a survey on the relationship between the pressure and the magnetic signal of ferromagnetic substance under the constant temperature condition.There are magnetic measurement of the magnetic material, the system due to noise problems using the lock-in amplifier technology, data acquisition of VB and MCU technology and other fields.High pressure material of magnetic measurement system is mainly of the technology of diamond anvil cell pressing on the sample. The main principle is based on the law of electromagnetic induction, the sample in the magnetic field, through the design of measurement scheme of the sensor part of the three coil(i.e. induction coil,and the excitation coil).After the phase locked amplifier technology,the computer calculates the magnetization curve, permeability and other data of the sample. The change of ferromagnetic substance under high pressure was studied by observing the variation of the curve.In this paper, the source of the original model has been improved, and the reliability of the system has been improved,at the same time, the phase transition and phase diagram of iron at high temperature and high pressure are simply introduced,, Magnetic signals under different pressures are measured by the magnetic measuring system of the material under high pressure.But due to the paper is just to verify the feasibility of the system, and the sensitivity and reliability of the system need further optimization,improving the system anti-jamming capability and reducing manual operations are work problems which need to be solved in the future.