## 1 Introduction  
Due to their improved formability and crash performance, advanced high-strength steels (AHSS) have been in the focus of the mobility sector for more than two decades. The group of AHSS generally includes steels with yield strengths (YS) and ultimate tensile strengths (UTS) exceeding 300 and 600 MPa, respectively [1, 2]. AHSS can be classified into several different generations. The first generation of AHSS, mainly steels with a ferritic structure, include dual-phase (DP) steels and transformation-induced plasticity (TRIP) steels with retained austenite, as well as complex phase (CP) and martensitic steels [3]. However, steels of the first AHSS generation are characterized by a high strength-high ductility discrepancy, i.e., a decreasing formability with an increase in strength. With the ongoing advance of globalization, a steady increase in the requirements being considered for new materials, material combinations and manufacturing processes can be recognized. Besides the constantly developing automation technology, light-weight design is often referred to as the innovation driver of the industry [4]. Current development is therefore focusing in particular on increasing resource efficiency, thus contributing to sustainability of products and processes. As a result, the simultaneous demand for materials with high strength and sufficiently good formability led to the development of the second AHSS generation, i.e., austenitic steels with high manganese contents [3]. In addition to nanoparticle-hardened, martensitic TRIP and twinning-induced plasticity (TWIP) steels,as well as the subgroup of density-reduced light-weight steels realized by adding high aluminum contents, TWIP and TRIP steels in particular have been in focus of scientific and commercial interest in the group of high-manganese steels (HMnS) due to their outstanding mechanical properties under monotonic loading [3; 5]. TWIP and TRIP HMnS are characterized by high strengths ranging from 500 to 1200 MPa and a concomitantly excellent formability of 40-70%, resulting in strength-ductility products between 40,000-50,000 MPa-% [6; 7]. As this value is limited to about 20,000 MPa-% for conventional steels, it is often used to express the high work-hardening potential of TWIP/TRIP steels as well as their excellent energy absorption capability [8]. In addition, HMnS TWIP and TRIP steels are characterized by a lower density of about 6.8-7.3 g/cm\({}^{3}\) compared to conventional steel counterparts [9; 10], eventually allowing for the development of weight-reduced crash-relevant body structures leading to a reduction in fuel consumption and CO\({}_{2}\) emissions. The group of austenitic HMnS, being firstly discovered by the work of Sir [PERSON] in 1888 [11], includes alloys with a manganese content between 10 and 35 wt.% [6; 7; 12]. The exceptional mechanical properties of these alloys can be attributed to the activation of multiple deformation mechanisms. Besides planar dislocation slip, deformation-induced twinning (TWIP-effect) as well as a mechanically driven solid-solid phase transformation from \(\gamma\)-austenite to either \(\alpha^{\prime}\)-martensite or \(\varepsilon\)-martensite (TRIP-effect) can prevail [13; 14]. The martensitic transformation is strongly affected by the thermodynamic stability of the phases being present and can therefore take place directly (\(\gamma\rightarrow\varepsilon\), \(\gamma\rightarrow\alpha^{\prime}\)) or in multiple transformation steps (\(\gamma\rightarrow\varepsilon\rightarrow\alpha^{\prime}\)). The contribution of the partially competing deformation mechanisms thereby depends on the level of the stacking fault energy (SFE) [13]. Due to the widely scattered literature data (cf. [14; 15; 16; 17; 18; 19; 20; 21]), a clear delimitation of the deformation mechanisms as a function of the SFE turns out to be difficult.