The microwave absorption properties and mechanism of 40Sm_0.5Sr_0.5Co_1-xMn_xO₃-60SrZrO₃ composites

Development of microwave absorption materials (MAMs) featuring thin thickness, wide bandwidth, and superior thermal stability remains a critical challenge for practical engineering applications. This paper systematically investigated the dielectric and microwave absorption characteristics of 40 wt%Sm_0.5Sr_0.5C_O1-xMn_xO₃-60 wt%SrZrO₃ composites. Remarkably, the Sm_0.5Sr_0.5C_O0.5Mn_0.5O₃-SrZrO₃ composite presents the widest bandwidth of 5.1 GHz with reflection loss < −5 dB at a thickness of only 1.4 mm, attributed to the optimal input impedance and a superior attenuation factor. Through comprehensive analysis of electromagnetic dissipation mechanisms, it revealed that the Mn⁴⁺ substitution of Co³⁺ leads to a reduction in conduction loss and an enhancement of both dipole polarization and interfacial polarization, while the eddy-current loss and magnetic resonances have contribution as well. These findings establish the Sm_0.5Sr_0.5Co_1-xMn_xO₃-SrZrO₃ (x = 0.5) composite as a promising candidate for microwave absorption applications, offering an optimal combination of thin-profile design and broadband performance.