Nanocomposite Permanent Film Of Magnetic Analog

The special properties of magnetic nano-particles has attracted more attentions and interests home and abroad. Micromagnetic simulation combining numerial computation with micromagnetic theory is believed to be the new research direction because they start with basic principles(exchange ,manetization, anisotropy and morphology) and yield hysteresis loops and magnetization patterns. According to the review of its condition and development at the present time, my paper systematically carrys on researching on it, in both trilayer film of Nd2Fe14B/α-Fe and multilayer film.Through the relationship between magnetic functions and soft magnetic thickness of Nd2Fe14B/α-Fe/Nd2Fe14B trilayer film, hysteresis loops of the system is just a rectangle ,and this moment,the trilayer films are in complete exchange-coupling area while the soft magnetic thickness is lower than the critical point(5nm); With the increase of the soft magnetic thickness, the coercivity of the trilayer films decreases monotonically, at the same time, the remanence and maximum energy products significantly enhance firstly and decrease later. Maximum magnetic energy product in the nanocomposite trilayer are obtained when soft magnetic thickness is 5 nm and hard magnetic thickness is 1 nm; namely, maximum magnetic energy product are 788.87kJ/m3(98.44 MGOe).From the two aspects of preparation, this paper analyses magnetic poor reasons of Nd2Fe14B/α-Fe/Nd2Fe14B trilayer film, and puts forward the corresponding measures to improve: first, we will further optimize main parameters of thin films deposition combining many, Second, we will improve the heat treatment process in order to improve the magnetic thin films, Third, a large number of alloying elements added in experiments can effectively control the size of the grain, better the microstructure and improve the comprehensive magnetic nanocomposite materials.Under the condition of unchanged Nd2Fe14B/α-Fe multilayer film thickness, the total thickness of magnetic layer and magnetic performance relationship indicate:Remanence and coercivity of the system are decreased gradually with increasing magnetic layer thickness, The maximum values of the maximum energy products of Nd2Fe14B/α-Fe multilayer films may obtain in the proper magnetic proportions and magnetic layer thickness.Under the condition of unchanged Nd2Fe14B/α-Fe multilayer film layers,while magnetic thickness is below 10 nm, the coercivity and maximum energy products increases gradually; however the coercivity and maximum energy products redudes greatly when magnetic thickness is above 10 nm. Remanence of the system original increases gradually and then decreases along with the increase of magnetic layer thickness, when the magnetic layer thickness of the multilayer film is exactly 5nm,the remanence now may reach the maximum value.