Composition Design And Performance Study On Soft Ferrite Stainless Steel

With the rapid development of automatic control technology,soft magnetic materials are applicated on electronic equipments more and more.Ferritic stainless steel is a common metal soft magnetic material.But compared with other soft magnetic materials,its magnetic properties are still inadequate,and need to be further improved.In addition,traditional soft magnetic materials need be plated to ensure its corrosion resistance,which increases pollution of the environment and the cost of production.It is necessary to develop corrosion-resistant soft magnetic material as well.In this paper,the effects of microstructure and chemical composition on the soft magnetic properties and corrosion resistance of ferritic stainless steel were studied based on the analysis of the current ferritic stainless steels.The composition,phase and microstructures of the alloys were characterized by X-ray diffraction(XRD),X-ray diffraction(XRD),backscattered electron diffraction(EBSD)and optical microscopy.Combined with the analysis of magnetic properties test and electrochemical experiments,the paper gets the following conclusions:(1)Cr and Mo elements in ferritic stainless steel have great influence on the magnetic properties;the addition of Ti,Si,Cu,Nb and Mn is beneficial to corrosion resistance;the grain size has a significant effect on the corrosion resistance and magnetic properties of soft ferritic stainless steels.(2)With the increase of annealing temperature and annealing time,the recrystallized grains become larger.The soft magnetic properties become better,when the grain size is 18?m.The effect of grain size on the corrosion resistance was not significant.(3)The order of influence on the soft magnetic properties by orthogonal experiment is Ti>Si>Cr>Mo,and the order of influence on the corrosion resistance is Cr>Mo>Ti>Si.The content of silicon element has little effect on the soft magnetic property,and the more silicon,the better the corrosion resistance.The addition of Cu has no significant effect on the magnetic properties,but the corrosion resistance can be remarkably improved.The effect of Al content on corrosion resistance is not obvious,and the soft magnetic property is better with the increase of Al content.The nickel has no obvious effect on the microstructure,soft magnetic and corrosion resistance.A small amount of rare earth elements can improve the microstructure and the soft magnetic properties.But too much rare earth elements has no significant effect on the soft magnetic properties and corrosion resistance.(4)Compared with the existing company samples,the soft magnetic properties of the new ferritic stainless steel improve significantly.The alloy with good properties contains Crl8.0%.Ti0.4%,Mo1.8%,Sil.0%,Cu0.6%,All.3%,Mnl.%,S0.05%,and C+N ?0.015%.