Effect Of Manganese On The Structure And Properties Of M Type Permanent Ferrites

Permanent ferrites,also known as hard magnetic ferrite,it can generate stable magnetic field only by externally supplying magnetizing energy once,and can continuously supply magnetic energy to the outside without continuously consuming electric energy,thus being a major material for saving energy.Due to its wide application field and good application prospect,M-type permanent magnet ferrite performance also needs further development.Element doping is the most effective and direct way to improve the performance of M-type permanent magnet ferrites.In this paper,element doping is used to improve the performance of ferrites,and the selection of raw materials is also considered to reduce production costs.At present,the main raw materials for producing permanent ferrite in China are red iron oxide and iron scale.And iron red as a raw material for production,the price is relatively high.Iron scale is the lowest price of raw materials,but because of its low purity of raw materials,containing a variety of other impurity elements,especially manganese elements will bring adverse effects in production,has been a big problem.Therefore,this paper will explore the influence of manganese elements on the performance of each series of permanent magnetic ferrite,and through the doping of other elements to improve the performance of M-type strontium ferrite,summed up its rules,hoping to provide a reference for production.The main research contents are as follows:?1?Mn-doped M-type permanent magnet ferrite SrFe_12-xMn_xO₁₉?x=0-0.28?was prepared by solid phase reaction method.The influence of Mn content on the structure and properties of M-type permanent magnet ferrite was investigated.XRD analysis showed that all the samples were pure phase ferrites.SEM images show that the incorporation of Mn element affects the uniformity of particle size in the sample,but does not affect the formation of the hexagonal structure.In terms of magnetic properties,the saturation magnetization of the sample has been showing a downward trend.After the doping amount x>0.24,the saturation magnetization decreases rapidly.However,the coercivity of the samples has been on the rise,and there is no abrupt change occurs.?2?Prepare and exploring that combine doping of three elements of La-Co-Mn on M-type strontium permanent magnet ferrite Sr_1-xLa_xFe_11.8-yCo_yMn_0.2O₁₉?x=-0-0.50;y=0-0.30?and the effects of various additives on the comprehensive properties of Sr_0.6La_0.44Fe_11.56Co_0.24Nn_0.2O₁₉ were also investigated.XRD results showed that all samples were pure phase.SEM images showed that all the samples formed hexagonal lamellar structure,and the particle distribution was uniform.With the increase of La-Co doping,the B,of the sample increased firstly and then decreased,and reached the maximum value when X=0.40 and Y=0.24.HCb and Hcj of the samples increased first and then decreased with the increase of doping amount of La-Co,and reached the maximum value when x=0.40 and y=0.24.During the use of additives,it was found that with the increase of Sio2 content,the remanent magnetization Br of the samples decreased and the intrinsic coercivity Hcj of the samples increased.The addition amount of SiO₂ was kept unchanged when CaCO₃-SiO₂ was used.The remanence Br and intrinsic coercivity Hcj of the samples increased first and then decreased with the increase of CaCO₃ content.The coercivity of the sample reached the maximum value when CaCO₃ content was 0.3wt%,and the remanent magnetization Br reached the maximum value when the additional amount was 0.3 5wt%.?3?Finally,the effect of La-Co-Mn-Nd substitution on the structure and properties of M-type permanent ferrite was investigated.The solid state reaction method was used to prepare Sr_1-xLa_xFe_12-2xCo_x(Mn_0.5Nd_0.5xO19?x=-0-0.4?ferrite.The results showed that the comprehensive properties of the samples were significantly improved after the combined substitution of various ions.The saturation magnetization Ms and the coercivity Hc of the sample increase first and then decrease with the increase of doping amount.At x=-0.2,both the saturation magnetization Ms and the coercivity Hc reach their maximum values.</sub>