Study on the effect of ball milling process on the absorption properties of carbonyl iron powder

Abstract

Using carbonyl iron powder with particle size of 3~5 as raw material, the carbonyl iron powder was treated by ball milling process, and the flake modified wave absorbent was prepared. Its electromagnetic parameters were analyzed, and its absorbing performance was predicted by simulation.Scanning electron microscopy (SEM), X-ray diffractometer (XRD) and vector network analyzer (VNA) were used to characterize the micromorphology, phase and electromagnetic parameters of samples at each stage, and the effects of ball milling process on the absorption properties of carbonyl iron powder were studied.The results show that the morphology of carbonyl iron powder is lamellar, the crystallinity of the original carbonyl iron powder is weakened, and its coercivity is increased.The anisotropy of the flake carbonyl iron powder is enhanced, the surface contact between the iron powder particles is increased,the electromagnetic parameters of the sample are improved.The minimum reflectivity of carbonyl iron powder moves to low frequency by ball milling.After ball milling for 3h, the sample has the strongest absorption performance. The reflection loss of the 3mm thickness material is less than -10dB in the wide band range of 3.45-6.3GHz.