Abstract:
The spherical nickel nanoparticles (an average diameter of 70 nm) were prepared by the wire electrical explosion method,Fe
3O
4 was coated on nickel to form the complete coverage by the co-precipitation method,and the silane coupling agent 3-mercaptopropyltrimethoxysilane (HS-(CH
2)
3Si(OCH
3)
3,MPTS) was used as a primer to improve the nickel surface.The as-synthesized Fe
3O
4/Ni composite particles were uniformly dispersed into the phenolic cement, then the mixture was pasted on the metal plate with the area of 200 mm×200 mm as the test board.The test of microwave absorption was carried out by the radar-absorbing materials (RAM) reflectivity far field radar cross-section (RCS) method. The results show that as a microwave absorber,the properties of the Fe
3O
4/Ni nanoparticles with core-shell structure are superior to those of Ni nanoparticles or Fe
3O
4 nanoparticles at the same mass quality ratios. Furthermore,with the content of Ni increasing,the microwave absorption performances of the as synthesized Fe3O4 /Ni nanoparticles are enhanced. At the same time,the absorption frequency ranges will shift to the high frequency sections when the contents of Fe
3O
4 increase.