Magnetic softness and interparticle exchange interactions of (Fe65Co35)1 − x(Al2O3)x (x = 0-0.50) nanogranular films

► (Fe65Co35)1 − x(Al2O3)x films were deposited by radio frequency magnetron sputtering. ► Increasing Al2O3 content decreases the average Fe65Co35 nanoparticle size. ► For 0 ≤ x ≤ 0.25, the lowest coercivity was achieved in the (Fe65Co35)0.82(Al2O3)0.18 film. ► Low coercivity is ascribed to the strong interparticle exchange interactions. ► The exchange interaction strength is related to the Al2O3 content.