The stability and reliability of power supply are crucial for driving economic growth and ensuring sustainable development. Among the factors threatening engineering equipment safety, metal corrosion is particularly significant, with iron (Fe), aluminum (Al), and their alloys being the most vulnerable to degradation. This review provides a systematic overview of the corrosion mechanisms, protection strategies, and monitoring technologies for Fe and Al metals and their alloys. The discussion begins with an analysis of the primary corrosion forms affecting these materials, emphasizing the role of environmental and material-specific factors. Advances in corrosion protection methods, including surface treatments, protective coatings, and the utilization of corrosion products to enhance material durability, are examined in detail. Furthermore, the application of real-time and unmanned platform technologies for corrosion monitoring is highlighted, with a focus on their potential to improve monitoring efficiency, accuracy, and safety evaluations. These technologies provide robust data and technical support for the development of targeted corrosion-resistant solutions. This review aims to offer insights into the current challenges and future directions in the study of Fe and Al corrosion resistance, serving as a reference for both researchers and practitioners in the field of engineering.

Hollow glass microsphere-reinforced epoxy hollow spheres (HGMS–EHSs) were prepared by a “rolling ball method” using expanded polystyrene beads, HGMSs, and epoxy resin (EP). The three-phase epoxy syntactic foam (epoxy/HGMS–EHS–HGMS composite) was fabricated by combining HGMS–EHS as a lightweight filler with EP and HGMS by a “molding method”. The HGMS–EHS and epoxy curing agent systems were well mixed by scanning electron microscopy. Experiments show that higher HGMS–EHS stack volume fraction, lower HGMS–EHS layer number, higher HGMS–EHS diameter, lower HGMS–EHS density, higher HGMS volume fraction, and lower HGMS density result in a decrease in the density of the three-phase epoxy syntactic foam. However, the above factors have the opposite effect on the compressive strength of the three-phase epoxy syntactic foam. Therefore, in order to obtain the “high-strength and low-density” three-phase epoxy syntactic foam, the influence of various factors should be considered comprehensively to achieve the best balance of compressive strength and density of the three-phase epoxy syntactic foam. This can provide some advice for the preparation of buoyancy materials for deep sea operations.

The heat generated by a high-power device will seriously affect the operating efficiency and service life of electronic devices, which greatly limits the development of the microelectronic industry. Carbon fiber (CF) materials with excellent thermal conductivity have been favored by scientific researchers. In this paper, CF/carbon felt (CF/C felt) was fabricated by CF and phenolic resin using the “airflow network method”, “needle-punching method” and “graphitization process method”. Then, the CF/C/Epoxy composites (CF/C/EP) were prepared by the CF/C felt and epoxy resin using the “liquid phase impregnation method” and “compression molding method”. The results show that the CF/C felt has a 3D network structure, which is very conducive to improving the thermal conductivity of the CF/C/EP composite. The thermal conductivity of the CF/C/EP composite reaches 3.39 W/mK with 31.2 wt% CF/C, which is about 17 times of that of pure epoxy.

Lightweight concrete is widely used in the construction industry due to its low density and high strength. In this paper, lightweight concrete was prepared by a simple two-step method. Firstly, the light calcium carbonate reinforced epoxy macrospheres (LCR-EMS) material was obtained by adhering calcium lighter carbonate powder to the expanded polystyrene foam spheres (EPS) material using the “balling method”. In the second step, the LCR-EMS was mixed with water, cement, and the hollow glass microspheres (HGMS) material using the “molding method” to obtain lightweight concrete. The combination of macroscopic photographs and microscopic morphology shows that the LCR-EMS material itself is uniformly encapsulated and well bonded to the matrix. Test results show that the density of the lightweight concrete decreases with an increase in the volume fraction of stacked LCR-EMS, the diameter, and the proportion of HGMS in the matrix, but it decreases with a decrease in the number of layers of LCR-EMS. The compressive strength of lightweight concrete exhibits a completely opposite trend. When three layers of LCR-EMS were used as filler material, the density and compressive strength of the concrete were 1.246 g/cm³ and 8.19 MPa, respectively. The density and maximum compressive strength of lightweight concrete were 1.146 g/cm³ and 6.37 Mpa, respectively, when filled with 8–9 mm-2L-90 svol% of LCR-EMS and 40 wt% of HGMS in the matrix. Compared with lightweight concrete filled with 90% EPS, the density increased by 20% while the compressive strength increased by 300%.