Influence of addition Ba-Ferrite on the hardness, magnetic properties and corrosion resistance of hybrid bonded magnet NdFeB

Abstract

The preparation of Hybrid Bonded Magnet based of NdFeB with additon of Ba-ferrite has been done with variation of Ba-ferrite (0, 3, 5, 8, and 10 % wt). Preparation process was started by mixing NdFeB (MQP-B+) powder with BaFe12O19, then mixed with binder Exopy Resin (5 %wt.) and compacted with pressure 40 MPa to form a pellet. Then samples pellet was heated by using Vacuum Dryer (10 mmbar) and temperature 90°C for 1 hour. Some parameters were measured such as vickers hardness, magnetic properties (flux magnetic density and hysteresis curve) and corrosion resistance. The best result of hardness test is hybrid bonded magnet NdFeB with compositions of 90 %wt NdFeB, 10 %wt Ba-ferrite and 5 %wt epoxy resin. Hardness value of hybrid bonded magnet NdFeB of this composition is = 265,13 HV. The best result for magnetic properties is hybrid magnet NdFeB with compositions of 95 %wt NdFeB, 5 %wt Ba-ferrite and 5 %wt epoxy resin. Those magnetic properties are Flux Density = 1340 Gauss, Br (remanence) = 3,827 kG, Hcj (coercivity) = 8,924 kOe and BHmax (Energy Product) = 2,847 MGOe. According the corrosion result test is found that sample with higher content Ba-ferrite has better corrosion resistance compare to sample with small content of Ba-ferrite.