A broadband and thin-layer microwave absorber is designed based on surface pattern design made by carbonyl iron and rubber composite. The bandwidth with reflection less than -10 dB covers the full X-band owing to two absorption peaks appeared simultaneously in both the simulation results and experimental results. In this work, the power loss and power flow diagram were present by CST simulation, which clearly explain the broadband absorption caused by double lambda/4 matching absorption and interfacial scattering synergistic effect. A facile splicing method was provided to extend the absorption bandwidth for the magnetic absorbing materials. (C) 2017 Elsevier B.V. All rights reserved.