To attain a balance between compressive strength and electromagnetic wave absorption performance, this paper combined two electromagnetic wave loss mechanisms (magnetic loss and electrical loss), and prepared an environmentally friendly alkali-activated slag/fly cementitious material (ASFC) using micron graphite (MG) as the absorber and ground granulated blast furnace slag (GGBS) and fly ash (FA) as the precursors. The conductivity, electromagnetic wave absorption characteristics and compressive strength of ASFC with different ratios of GGBS and FA, MG size (800 mesh, 320 mesh, and 100 mesh), and content were investigated. The results indicated that when the ratio of GGBS and FA was 7:3, natural resonance and eddy current loss contributed to electromagnetic waves absorption at 8.2–11.0 GHz and 11.0–15.5 GHz range respectively. Additionally, the conductivity of MG/ASFC showed typical percolation characteristics, with the percolation threshold reached at a dosage of 3 wt%. In the 8.2–18.0 GHz, the incorporation of MG significantly augmented the conductive loss and polarization loss of ASFC. Furthermore, smaller-size MG was more beneficial for facilitating conductive loss of MG/ASFC among three different sizes. By adding 2 wt% of MG with 800 mesh, MG/ASFC can achieve a minimum reflection loss of −27.8 dB with a bandwidth of 3.0 GHz (Reflection loss ˂-7 dB). However, when compared to other cement-based absorbing materials reported, the MG/ASFC prepared in this experiment demonstrated better compressive strength and wave absorption properties. This finding contributing to a better understanding of green building materials with electromagnetic radiation protection capabilities.

中文翻译：

---

微米石墨与粉煤灰协同碱活化胶凝材料的电磁吸收特性及机理

为了达到抗压强度和电磁波吸收性能之间的平衡，本文结合两种电磁波损耗机制（磁损耗和电损耗），利用微米石墨（MG）制备了一种环保型碱激发矿渣/飞粉胶凝材料（ASFC） ）作为吸收剂，磨碎的粒化高炉矿渣（GGBS）和粉煤灰（FA）作为前体。研究了不同GGBS与FA配比、不同MG尺寸（800目、320目、100目）、含量的ASFC的电导率、电磁波吸收特性和抗压强度。结果表明，当 GGBS 和 FA 的比例为 7:3 时，自然谐振和涡流损耗分别有助于 8.2-11.0 GHz 和 11.0-15.5 GHz 范围内的电磁波吸收。此外，MG/ASFC的电导率表现出典型的渗流特征，在3 wt%的剂量下达到渗流阈值。在 8.2-18.0 GHz 范围内，MG 的加入显着增加了 ASFC 的传导损耗和极化损耗。此外，在三种不同尺寸之间，较小尺寸的MG更有利于促进MG/ASFC的传导损耗。通过添加 2 wt% 的 800 目 MG，MG/ASFC 可以在 3.0 GHz 带宽下实现 -27.8 dB 的最小反射损耗（反射损耗 ˂-7 dB）。然而，与报道的其他水泥基吸波材料相比，本实验制备的 MG/ASFC 表现出更好的抗压强度和吸波性能。这一发现有助于更好地了解具有电磁辐射防护能力的绿色建筑材料。