... to surface oxidation or rust,and elimination.Users should consider magnet coating,plating or suitable surface treatment.5) Less prone to ... magnetic properities than ceramic,higher than SmCo type rare earth magnet.7) Irreversible loss at high temprature.8) Types:N30, ... ,N50 and N529) High energy ranging from 8MGOe to 48MGOe with wondrerful coercive force.10) Less expensive,and mechanically stronger and ...