Chain-like and diamond-shaped magnetic particle agglomeration (MPA) commonly forming in a weak magnetic
field are simulated based on the finite element method (FEM), and the effects of particle diameter, magnetic
field strength, particle relative magnetic permeability, and particle number in magnetic particle chains
(MPCs) and diamond-shaped MPA on the strength of MPA are analysed in detail. The results show that magnetic
forces on the centre contact points (CCPs) of MPA are positively correlated with the particle diameter,
magnetic field strength, particle relative magnetic permeability, and particle number. In addition, the forces on
the CCPs of the MPCs (N=2) have a square relationship with the particle diameter and magnetic field strength
and have a power relationship of 1.25 with the particle relative magnetic permeability. The forces on each contact
point decrease slowly from the centre to both ends in the MPCs and then rapidly decrease to one value
(approximately 0.779 times the forces on the CCPs). As for the diamond-shaped MPA, with the increase in the
angle α between the magnetic field and axis of diamond-shaped MPA, the force magnitude of the particle
entrained parallelly in the diamond-shaped MPA shows a trend of a “cosine curve” shape and the minimum
value is 2109 times that of the entrained particle’s gravity. The angle θ between the direction of the force and
the negative X-axis shows a trend of a “sine curve” shape. When α = 25º and 155º, the angle θ of the force on
the entrained particle reaches an extreme value, that is, θ = 21.87º. Only if the angle θ reaches 30º can the particle
entrained parallelly escape from the diamond-shaped MPA. Thus, the diamond-shaped MPA remains in a
stable state and it is difficult to disperse MPA by changing the direction of the magnetic field.