Magnesium alloys have a high strength-to-weight ratio [1], which makes them an ideal material for transport and aeronautical applications. The magnesium alloy Mg-4Y-3RE (WE43) is designed to have excellent mechanical properties and corrosion resistance. Additive manufacturing of WE43 alloy present numerous differences compared with traditional manufacturing techniques of the same alloy [2]. Various additive manufacturing techniques using powder metal are available. In this study, substrates are manufactured by a laser powder bed fusion (L-PBF) process, that allows for layer-by-layer manufacturing, where heating and cooling occur at very high rates of speed [3]. The problem with Mg and its alloys is the high corrosion rate because Mg is a very reactive element. In the medical sector, this is not a problem if an implant is to be reabsorbed. In the case of the aeronautical and transport sector, a high corrosion rate means the loss of mechanical properties and, finally, the loss of structural integrity of the part. For this reason, alloys such as WE43 are designed, which make the material more resistant to aggressive environments, but still have high degradation rates compared to other materials. A possible solution is to apply a coating that isolates the base material (WE43) from the aggressive environment by using polymeric coatings. In this way, applying epoxy coatings to metallic surfaces is a common strategy to protect them from aggressive environments and avoid corrosion problems. Epoxy resins have notable chemical inertness and good capability to generate adhesive joints. After proper preparation of the substrate surface and resin method of application, the epoxy coatings can provide long-time protection with notable barrier properties [4]. However, thermosets have a permanent high crosslinked structure that gives them inherent brittleness and avoids its reconfiguration. To solve these issues, we develop in this work an epoxy coating based on Diels-Alder and disulfide bonds which can be disengaged to eliminate cracks and damage [5,6], and we evaluate the manufacturing parameters to get a functional coating. Thus, the influence of the coating on the corrosion resistance of the WE43 substrate, and its repairability to increase lifetime and protection are evaluated.