Abstract: In this paper, the effect of fractal dismension (D) in coercivity (H₀) of single-domain particle aggregates is discused. Making use of dpole field approximation,an expression relatng D and H₀ is derived,which states that H₀ is a deoreasing function of D. By analyzing the relati n between D and packing density (p),it is found that th.obtained conclusion is consistent with the existing theoretical and experimental results.

Key words: aggregate, fractal dimension, coercivity of single-domain particle