Study On The Preparation Process Optimization Of Pure Iron Soft Magnetic Material

Pure iron soft magnetic material is a kind of soft magnetic material with low price and wide application.However,due to the large number of pores,high content of internal impurities and low density of the materials prepared by traditional powder metallurgy process,their magnetic properties are lower than those prepared by casting and forging method.Therefore,optimization of the preparation process is the key to improve the magnetic properties of the materials.This paper adopts the water atomized iron powder as the raw materials,powder metallurgy method for the preparation technology,through the study of the screening of raw material iron powder and annealing treatment,the normal temperature,temperature,pressure and vacuum to neutralize the means of combination of powder forging and heat treatment after forging work art preparation high saturation magnetization,low coercive force of pure iron soft magnetic materials,using XRD,SEM and metallographic microscope observation methods,explore the organic connection between density and magnetic materials,so as to optimize the preparation technology.The initial pressure density of the material has an important influence on the improvement of its magnetic properties.At room temperature,the initial pressure density of iron powder is 7.53g/cm~3,the saturation magnetization is 1.76T,and the coerciousness is 2.02Oe.Under the condition of vacuum pressing,the initial pressure density of the material was up to 7.56g/cm~3,the saturation magnetization was 1.93T,and the coerciousness was1.48Oe.The initial pressure density of the process material is 7.66g/cm~3.However,without forging treatment,the saturation magnetization was only 1.12T,and the coerciousness was38.9Oe.The 100 mesh iron powder was screened after vacuum annealing at 700?,pressed at 1200MPa,then hot-forged at 1100?and 969MPa,sintered at 1450?,and annealed at 900?.The final density of the material was 7.77g/cm~3,the saturation magnetization was 1.93T,and the forced force was 1.48Oe.The saturation magnetization can exceed 0.2T of soft magnetic parts prepared by traditional casting and forging method.