<正>Exchange interaction plays an important role on magnetic properties of nanocomposite magnets consisting of hard- and soft-magnetic phases.Here the exchange interaction in the Sin-Co/Co (and Fe65Co35) magnetic films was characterized by measuring static (mr(H)) and demagnetized (md(H)) remanence curves.According to conventional method:δm(H)=md(H)-[1-2mr(H)],the exchange interaction was evaluated.The switching fields H′p and Hp,at which static (mr(H)) and demagnetized (md(H)) remanence show the fastest change,were identified.The relative ratioη=(Hp-H′p)/Hp of switching fields H′p and Hp has a linear relationship with the maximum valueδmmax ofδm(H) curves,proposing an alternative way to characterize the exchange interaction.