Performance Study Of Soft Magnetic Materials Prepared By Laser Additive Manufacturing

With the advancement of technology,especially the rapid development of the electronic information industry and the continuous demand of the market,the research and development of electronic products is increasingly trending towards intelligence,small size,energy saving,and high efficiency.The continuous progress of artificial intelligence technology and the popularization of intelligent wearable devices require magnetic components to have greater power,lower power consumption,stronger flexibility,larger capacity,and faster transmission rates,while the size of the power supply is constantly shrinking.Iron-based magnetic powder cores are a type of cost-effective metallic soft magnetic composite material that have broad application prospects in fields such as pulse transformers,energy storage filter inductors,and circuit filters.However,with the increase of application frequency,eddy current loss intensifies.Eddy current loss can cause a large amount of heat generation in the magnetic core and reduce the relevant magnetic properties of the magnetic powder core.Therefore,how to reduce eddy current loss and develop energy-saving soft magnetic materials is currently a hot and difficult research topic.New high-performance soft magnetic materials will be developed toward high saturation magnetic induction strength,permeability,resistivity and Curie temperature as well as low coercivity and high frequency losses.Laser additive manufacturing can be prepared into special shapes to meet industrial applications depending on the application environment.In this paper,we optimize and innovate from the direction of laser printing to develop new high-performance soft magnetic materials,improve the resistivity of the alloy itself to reduce the intra-particle eddy current loss,and control the residual internal stress to reduce the hysteresis loss through process optimization of the molding and heat treatment processes.This paper compares the magnetic properties of soft magnetic materials prepared by additive manufacturing and traditional molding method;then compares different soft magnetic materials and explores the soft magnetic materials more suitable for laser printing;finally uses the advantages of laser printing to design different structures to further optimize the magnetic properties of soft magnetic materials.In the comparison of the performance of soft magnetic materials prepared by additive manufacturing and traditional molding,four different phosphating solutions were selected.Among them,the iron powder coated with the phosphating solution containing manganese nitrate and sodium molybdate exhibited excellent comprehensive performance.Compared with samples prepared by traditional forming,the samples synthesized through 3D printing showed significantly increased permeability and a certain degree of reduced coercive force,greatly improving the overall magnetic performance.The phosphating film on the surface of the reduced iron powder can block the conduction path of induced currents in alternating magnetic fields and reduce losses.Four soft magnetic materials,reduced iron powder,MnO2-coated iron powder,Fe-30Ni,and Fe-6.5Si,were prepared by laser metal deposition technology,and their various magnetic properties were compared.Fe-6.5Si performed well in dynamic magnetic performance due to its high effective permeability and low loss,exhibiting better performance in high-frequency applications.This is due to its spherical structure and higher sintering density,both of which are conducive to improving the material’s magnetic conductivity and stability.The influence of different laser powers on the performance of Fe-6.5Si soft magnetic materials was studied,and it was found that materials prepared at a laser power of 1200 W exhibited better performance.Furthermore,after annealing heat treatment at 1000℃,the magnetic properties of the material were further improved.Additive manufacturing has the capability to manufacture complex-shaped parts.In order to fully utilize its advantages of design flexibility,rapid prototyping,high material utilization,and no need for assembly or molds,four different ring-shaped samples with Fe-6.5Si soft magnetic material as the experimental material were designed and prepared,and their magnetic properties were tested.In order to improve printing accuracy,selective laser melting was used to prepare Fe-6.5Si soft magnetic materials with different structures.At the same time,through experimental research,it was found that this new type of structured material has better performance,with higher magnetic saturation strength and lower magnetic loss.Through the preparation and performance analysis of iron-based soft magnetic materials,this paper successfully prepared a new type of soft magnetic composite material with a novel structure,providing new ideas and directions for the research and application of soft magnetic materials.