## 1 Introduction
The literature identifies six main mechanisms of adhesion [41; 42]: absorption [43], electrostatic attraction [44; 45], chemical bonding [46], mechanical interlocking [47; 48; 49], diffusion [50], and a weak boundary layer [51]. A proper compatibility of the interface between both substrates desired is of extreme importance to form the adhesive joint. A mixture of adhesion mechanisms is usually responsible for a given system [52], since a definitive conclusion on which mechanisms best suit adhesive bonding is still lacking. Surface treatments are currently being used to improve this adhesion. An increase in the friction coefficient correlates with an increment in the surface roughness of the material [53; 54]. Furthermore, an increase in wettability when combining the incorporation of polar functional groups to a polymer joined with a silicon coated steel positively influences the adhesion strength [54; 55]. The grit-blasting technique is believed to be the ideal surface treatment for metallic media [43; 56; 57]. Despite these surface treatments, some substrates may still provide only negligible adhesion. At this point, primers or adhesive promoters may come to aid with further improvements of the joining strength [58; 59]. The adhesion strength evaluation can be performed by mechanical tests (tensile, shear and peel tests) [60], or by nondestructive tests [61], which also permit the assessment of damage of the joints [62]. Previous works explored the potential of ABS and polyamides (PA) in terms of being successfully coated with metals, evidencing the potential of using these polymers when joining dissimilar materials [63; 64; 65; 66]. The ABS arises as an ideal choice for engineering applications, as it possesses high toughness, mechanical strength, good thermal stability, and cheapness, to name a few advantages of it [36; 67; 68; 69; 70]. On the other hand, reinforced PA can also be classified as a high-performance engineering material, since the presence of fillers within a PA matrix enhances its mechanical properties and decreases the influence of humidity [71]. Some constraints must be pointed out with regard to using these polymers in FFF applications. The most inconvenient one for the conduction of this experiment was the warping effect (a non-wanted distortion on the surfaces of a part), which is already extensively described in numerous papers and is frequent when printing with PA and ABS filaments [72; 73]. In recent years, several works reported the use of AM to produce parts with polymer-metal hybrid materials (PMHM), demonstrating the timeliness and growing interest in this technology. The first study of this technology using AM was undertaken by [PERSON] et al. [74], where the design and manufacturing of products with embedding components through a layered process termed Shaped Deposition Manufacturing was addressed. This work presents a combination of process planning algorithms and manufacturing methods for the design of parts with PMHM, and provides an insight into the multiple applications of these components in industries such as automotive and electrical systems [74]. In addition to aspects related to product design and process planning, it is crucial to study the mechanical properties of parts produced with PMHM in order to successfully implement this technology. The mechanical properties of PMHM structures comprised of a photoresin and an amorphous layer metal (NiB) obtained by 3D printing and electroless deposition, respectively, were studied in the work of [PERSON] et al. [75]. The authors focused on the deformation mechanisms and energy absorption capability of cellular structures produced with these PMHM, and found that chemical bonding is essential in promoting a good adhesion between the polymer and metal in these microstructures. The mechanical properties of PMHM joints obtained by a combination of laser powder bed fusion (LPBF) and FFF processes were studied in the work of [PERSON] et al. [55].