Figure 1
From: Characteristics and FEA verification of the attraction between like magnetic poles
The curves of force vs. distance between like poles show attraction at a sufficiently small distance for NdFeB pairs. In Series #1 (thin magnet pairs), the pairs of N55 magnets with Pc ratios of 10.8 (not shown here), 4.69 (a), and 2.15 (b), all show the transition from a repelling force to an attracting force for the center-aligned pairs, but such a transition is absent for the edge-aligned pairs. The N48SH pairs with Pc ratios of 4.69 (c) and 10.8 (not shown here) also exhibit the same features as the N55 pairs. This indicates that the LD effect is stronger in the center-aligned than in the edge-aligned for the thin magnet pairs. In Series #2 (thick magnet pairs), the pairs of N55 with Pc ratios of 17 to 185 show negligible force differences between the center-aligned and edge-aligned (d). Two pairs with larger Pc ratios of 85.7 and 185 show the transition from repelling to attracting, and the other two pairs with smaller Pc ratios of 17 and 39.3 do not have such a transition.
