## 1 Introduction  
Additive manufacturing (AM) is a rapidly growing process with advantages over traditional processes [1]. It provides significantly reduced design constraints, structural optimization, flexibility, and material-saving characteristics with a wide range of applications in the aerospace, automotive, and biomedical industries [2, 3]. The growing use and diversity of parts produced during AM enhance the need for the in-depth study of their mechanical properties [4, 5, 6]. The most widely used methods for the AM of metallic materials are powder-fed systems such as electron beam melting (EBM), selective laser sintering (SLS), and selective laser melting (SLM). Among the popular methods mentioned above, SLM is the most popular method for the AM of metal powders for flexibility in the production of all cstable materials, the high quality of parts produced in a short time, and the high resolution for complex-shaped parts. The aerospace, automotive, and marine industries focus on powder bed SLM technology for Ti-alloy, Ni-superalloy [7, 8], Ni-based alloys [9], stainless steel [10, 11], and Al-based alloys [12, 13, 14] components. AlSi10 Mg was used in additive manufacturing for its good mechanical properties such as an excellent compromise between lightness, strength, limited restriction, and a high resolution for complex shapes and structures and a short printing time. Given the almost eutectic composition of Al and Si, a great weldability can be achieved. Mg plays an important role in age hardening in the form of \(\beta^{\prime}\) and Mg\({}_{2}\)Si (\(\beta\) phase) [15]. Recently, many works have been published on the microstructure using a study of the processing parameters of AlSi10 Mg fabricated by SLM [16, 17]. During the fabrication of mechanical parts in the SLM process, the orientation of the construction has direct effects on the anisotropy and microstructural heterogeneity of SLM components, especially in AlSi10 Mg. In most cases, the crack path in AlSi10 Mg is strongly influenced by microstructural heterogeneity [18; 19; 20]. Obtaining an equiaxed grain remains a challenge, since the cooling rate is high in the range of 106-108 \({}^{\circ}\)C. Several investigations demonstrated that the orientation of construction remains a major challenge, mostly for AlSi10 Mg built in SLM, whose cracking trajectories in most cases are related to microstructural heterogeneity. Therefore, it is important to understand the intrinsic behavior of this component built on different orientations [6; 21; 22]. Many authors propose methods for monitoring the mechanical characteristics of specimens based on the acoustic emission (AE) technique. This is a passive, non-destructive evaluation (NDE) technique used to detect and study specimen damage at a microscopic scale. The acoustic waves generated contain information about the initiation and progression of damage. These acoustic waves can be recorded using a piezoelectric sensor. The recorded waveform can be analyzed in terms of its time-frequency properties to obtain information on the onset of damage and its evolution. The study of these AE waveforms can help in understanding the characteristics of the damage [23; 24]. Currently, there are few research papers regarding the damage characterization of the AlSi10 Mg specimen obtained by the SLM process using the AE technique [25; 26; 27]. However, the AE technique has been successfully used for the damage characterization of other specimens obtained by other additive manufacturing processes. For example, [PERSON] et al. studied the characterization of fatigue damage in 304L steel by the AE technique for different total strain amplitudes. Through the parameter-based approach, a correlation between the acoustic signals and the damage evolution during the fatigue tests was obtained [28]. [PERSON] et al. monitored the delamination process of 3D parts obtained during the Fused deposition modelling (FDM) process.