## 1 Introduction  
Fused Deposition Modeling (FDM) has revolutionized the field of additive manufacturing by enabling the creation of complex three-dimensional objects with precision and efficiency [1]. This technique involves the extrusion of molten thermoplastic materials through a heated nozzle, layer by layer, to build up the desired object. However, the quality, strength, and functionality of the printed parts heavily rely on the properties of the materials used [2]. The most popular materials used in FDM printing are thermoplastics such as acrylonitrile butadiene styrene (ABS) and polylactic acid (PLA). These materials offer a good balance of affordability, ease of use, and availability, making them widely adopted in FDM 3D printing. ABS is a versatile thermoplastic known for its excellent impact resistance, strength, and durability. It can withstand higher temperatures compared to PLA, making it suitable for functional parts, prototypes, and mechanical components. PLA is a biopolymerand environmentally friendly thermoplastic derived from renewable resources such as stomach or sugarcane. It offers ease of printing, low odor, and comes in a wide range of colors. PLA is commonly used for prototypes, hobbyist projects, and decorative objects. While PLA is not as heat resistant as ABS, it is more rigid and generally exhibits better print quality [3]. Apart from ABS and PLA, there is a growing variety of specialized materials catering to specific applications and requirements. PET-G is a popular choice for its durability, transparency, and ease of printing. It offers improved impact resistance compared to PLA and is less prone to warping than ABS. PET-G is commonly used for functional parts, mechanical components, and packaging applications [4]. Filaments combine a thermoplastic matrix with finely ground wood or metal particles, the so-called PLA WOOD/Woodfill or Metal Composite Filaments. This specialty results in printed objects with a wood-like or metallic appearance. They are popular for artistic and aesthetic purposes, architectural models, and decorative objects [5]. Flexible filaments, such as Thermoplastic Polyurethane (TPU), offer elasticity and stretchability, enabling the creation of flexible parts and gaskets [6]. In recent years, significant progress has been made in developing a wide range of materials specifically tailored for FDM 3D printing. These materials exhibit enhanced characteristics, including mechanical strength, heat resistance, flexibility, and even electrical conductivity, opening up new possibilities for various applications. The availability of diverse materials has expanded the capabilities of FDM printers, making them suitable for prototyping, tooling, customized manufacturing, and even functional end-use parts [7; 8]. It is well known that common 3D printing polymers such as nylon and polylactic acid (PLA) can significantly degrade their material properties when exposed to high temperatures and humidity for a long time. The ability of a material to absorb moisture is influenced by various factors, including the matrix and reinforcement materials, as well as the surrounding temperature, humidity, and duration of exposure to the challenging environment. In polymers, the ingress of moisture occurs through the diffusion of water molecules within the material. These water molecules are transported into the interior of the polymers through random molecular movements, and the absorption and diffusion rates are highly dependent on temperature and the inherent moisture content. At a microscopic level, the diffusion of moisture is significantly affected by the polarity and degree of crosslinking of the polymer, as well as the presence of residual monomers, hardeners, or other hydrophilic substances. The effect of water on a thermoplastic material is more pronounced when it is immersed in a liquid form compared to being in a vapor environment.