## 1 Introduction  
The layer-by-layer design of components made of shapeless raw material is known as additive manufacturing [1]. If this takes place outside a limiting build space and the raw material is melted by means of an electrical arc, the definition of the arc-based free-space process is fulfilled [2]. The basic prerequisite for an error-free and flexible manufacturing process is an exact knowledge of the relationships between the predefined process parameters, construction conditions and the resulting component geometry. The necessity for this is illustrated below by comparing the classic Plasma Transfer Arc technology (PTA) with the additive 3D Plasma Metal Deposition process as an example. The 3 DPMD process is based on the classic PTA [3; 4; 5] The conventional aim of the PTA process is to enhance the resistance of the component surface to aggressive media, corrosion, abrasion or to replace missing material [6; 7]. For this purpose, several welding beads are usually applied to the base material in three to five layers similar to a carpet. Due to this low number of layers, the build-up characteristics are two-dimensional. As a result, any deviations in the resulting bead width or weld seam height do not have a significant effect on the coating or the process quality and are, therefore, of minor importance. However, additive components often require a high number of layers, with a defined and reproducible slice distance per layer. Therefore, the exemplary deviation of \(-0.1\) mm per layer with a number of 200 layers leads to an increase in the arc length from 10 mm to 30 mm. As a result, the arc voltage increases (=higher heat input) steadily due to the increased arc resistance, resulting in unstable arc conditions with the consequence of process interruption [8; 9]. Therefore, the aim of these studies was to detect and evaluate correlations between the process- or build cycle parameters and the resulting component geometry. Based on this, control variables were defined, and the process' stability and flexibility were increased. Thus far, the powder-based PTA process in the context of additive manufacturing has mostly been considered with a focus on the presentation of the process potential by the production and characterization of demonstrator components. [PERSON] et al. [10] described the production of hybrid components made of aluminum oxide ceramics (Al\({}_{2}\)O\({}_{3}\)) and a nickel-based alloy. A variation of the parameters as well as their influence did not occur. The same applies to [PERSON] et al. [11], where the focus was on the evaluation of the microstructure of the beryllium component produced by PTA and the determination of its mechanical and technological properties. The possibility of preparing components from 17-4 PH stainless steel through PTA was described in [PERSON] et al. [12]. [PERSON] et al. [13] and [PERSON] [14] used the process for the production of large components (7300\"7300\"4870 mm) at a maximum melting rate of 22.67 kg/h. No statements were made on general correlations. The manufacturing of simple geometries using PTA in combination with a subtractive process was described in [PERSON] et al. [15] and [PERSON] et al. [16]. In an earlier publication, [PERSON] et al. [17] showed that the welding current has a large influence on the part geometry, the powder feed rate has a small influence and the welding speed has a medium influence. Quantitative statements are not provided. [PERSON] et al. [18] described the relationship between the variation of various process parameters and the component geometry for the micro plasma process. It was described that with increasing welding speed, both the height of the component and the layer width decreased in equal relationship. An increase in the welding current, on the other hand, led to opposing behavior. In this case, the layer height decreased, and the wall thickness increased with an increasing welding current. The variation of the powder feed rate had a positive effect on the layer height at a significant level.