## 1 Introduction  
In polymer powder bed fusion additive manufacturing, anisotropic behavior of the material leads to the variation in dimensional and mechanical properties depending on the part orientation. Since this technology has obtained attention from automotive, aerospace, and medical industries as a technology for producing end-use parts, requirements for part quality have increased significantly, including the need for consistent results. Therefore, the development of new models for the prediction of mechanical properties will allow meeting these requirements. The current state-of-the-art [1; 2; 3; 4; 5; 6; 7; 8; 9; 10; 11; 12; 13; 14; 15; 16; 17; 18; 19] describes the importance of part orientation, powder morphology, and machine process parameters as a means towards the control and management of variation in polymer powder bed fusion system. Among the most investigated additive manufacturing (AM) machine process parameters are laser power, scan speed, hatch distance, scan strategy, beam speed, melting temperature, and powder bed temperature [2; 3; 4; 5; 6; 7]. There is a number of studies [20; 21; 22] which report that laser power, scan speed, hatch distance, and layer thickness can be used to define the line energy and how their variation may influence mechanical properties of the part. In addition to energy applied to solidify polyamide, [PERSON] et al. [8] have also reported the importance of layer thickness, and powder distribution in each layer. Powder distribution is dependent on the size of the particles in the powder and powder viscosity. Futhermore, [PERSON] et al. [18] and [PERSON] et al. [23] studied how the size of the particles of the polymer powder and its viscosity influence mechanical properties. While [PERSON] et al. [18] investigated the degradation behavior of PA12 based on the analysis of phase transition temperature and melt viscosity for both virgin and aged powder, [PERSON] et al. [23] have reported that the size and morphology of the particles could lead to the creation of pores, gaps, or/and voids in the fabricated parts. Thus, [PERSON] et al. [22] have proposed to use a machine vision in combination with Design of Experiment (DOE) to monitor and control powder morphology. In order to control powder flowability, the authors described how machine process parameters need to be varied (e.g., line energy, change the speed of the recoater, adjust layer thickness). The influence of part orientation on mechanical properties has already been described in detail by [12; 24; 25]. Besides, there is a difference between what is reported in the literature and what is provided by EOS data sheets. While [12; 24; 25] have reported that Tensile modulus, Elongation at break, and Maximal Stress are affected by the part orientation, EOS reports in their data sheets for PA12-Balanced process parameters group that Tensile Modulus is the same in all orientations. [PERSON] et al. [26] have also reported that part orientation has the most significant influence on mechanical properties among other investigated parameters based on the Taguchi DOE. Besides, [PERSON] et al. [12] reported that the thermal distribution in the build chamber also has an impact on the mechanical properties of the fabricated parts. However, there is a limited number of studies that have attempted to predict mechanical properties based on the part positioning in the build chamber. Similar research was performed for the investigation of dimensional accuracy for PA12 based on the part positioning in the build chamber, part orientation, and STL model properties (number of mesh triangles, volume, and surface) [11]. Using a similar strategy would contribute to the development of the schematic approach of positioning parts in the build chamber based on their requirements, and thus an increasing area of build chamber utilization, which would lead to cheaper and more sustainable production.