Multi-hexaferrites (Sr_3-xM_xCo₂Fe₂₄O_a; M = none, La, Ca, Ce, Y; x = 0.3) with more than two types of hexaferrite phases were synthesized by solid-state reactions and doping of various cations in the Z-type Sr₃Co₂ hexaferrite. Multi-hexaferrites consisting of Z + U + W, W + M, X + W, W + M, and X + W + Z phases were formed in the samples with M = none, La, Ca, Ce, and Y, respectively, upon first and second calcinations at 1160 and 1210 °C. The microstructures were observed by scanning electron microscopy. M–H curves of the sintered bodies were measured using a B–H loop tracer. Complex permittivity and permeability measurements (100 MHz ≤ f ≤ 18 GHz) were performed on hexaferrite–epoxy composite samples. The microwave absorption properties were evaluated by reflection loss (RL) calculations based on the complex permittivity and permeability spectra. For the undoped sample, the minimum RL (-47.6 dB) corresponding to the maximum microwave absorption was obtained at f =4.5 GHz and thickness d =4.6 mm. The frequency corresponding to the RL peak was increased up to 17.3 GHz, while the optimal thickness gradually decreased upon the doping with Ca, Y, Ce, and La cations. The peak shift to high frequency is attributed to the increase of magnetic hardness of the mult-hexaferrites. Broad-band EM absorption properties are also achieved owing to the overlaps of the hard–soft magnetic properties of the multi-hexaferrites.

 通过固相反应和掺杂合成了具有六种以上六种铁素体相的多六铁素体（Sr _{3- x} M _x Co ₂ Fe ₂₄ O _a； M =无，La，Ca，Ce，Y；x = 0.3）。 Z型Sr ₃ Co ₂六价铁氧体中各种阳离子的分布 在样品中分别形成了由Z + U + W，W + M，X + W，W + M和X + W + Z相组成的多六方铁氧体，其中M =无，La，Ca，Ce和Y在1160和1210°C下进行第一次和第二次煅烧。通过扫描电子显微镜观察微观结构。烧结体的M–H曲线是使用B–H测量的循环跟踪器。复杂的介电常数和导磁率的测量（100兆赫≤ ˚F ≤18千兆赫）的六方晶系铁氧体上的环氧复合材料样品进行的。通过基于复介电常数和渗透率谱的反射损失（RL）计算来评估微波吸收特性。对于未掺杂样品，在f = 4.5 GHz和厚度d下获得了对应于最大微波吸收的最小RL（-47.6 dB）= 4.6毫米。与RL峰相对应的频率增加到17.3 GHz，而掺杂Ca，Y，Ce和La阳离子时，最佳厚度逐渐减小。峰移至高频归因于多六方铁氧体的磁硬度增加。由于多六方铁氧体的软磁特性重叠，因此还实现了宽带EM吸收特性。