The results of XRD analysis of obtained AZ31-xLi alloys are shown in Fig. . The obtained data indicate that the AZ31-4Li mostly consists of an HCP structured a-Mg phase (α-Mg). An increase in the lithium content leads to a shift of α-Mg reflexes to larger 2θ , and the occurrence of the reflexes corresponding to a BCC β-Li phase, which dominates in the case of the AZ31-12Li alloy. XRD patterns of all alloys also have low-intensity reflexes at 2θ ca. 23 and 40°. The AZseries Mg alloys usually have Mg-Al, Al-Mn, and Al-Mn-Zn IMPs . Recently, Znang et al. The surface microstructure of the obtained alloys was examined by SEM, as can be seen in Fig. . The amount of Li plays a decisive role in the microstructure of the obtained alloys. The direct use of the EDX analysis for the detection of lithium and examination of its surface distribution is not possible as more advanced techniques should be used . Therefore, in the qualitative analysis of the microstructure of the AZ31-хLi alloys, the phase assignments were based on the possibilities of the electron backscattering mode of the SEM. In this case, the lighter areas correspond to elements with a higher atomic number (α-Mg), and the darker areas correspond to elements with a lower atomic number (β-Li) . The principal constituents of the AZ31-4Li alloy are IMPs distributed in the α-Mg alloy matrix (Fig. ). The size of the IMPs does not exceed 10 µm. In the case of the AZ31-8Li alloy (Fig. ), two main phases α-Mg (lighter regions) and β-Li (darker regions) with increased number of IMPs. The AZ31-12Li alloy (Fig. ) mostly contains the β-Li phase with a further increased number of IMPs. The observed microstructures also support the results of the XRD analysis (Fig. ) and the formation of Al-Li-type IMPs in these Mg alloys. In each panel, areas marked with numbers correspond to points of EDX analysis listed in Table The quantitative EDX analysis of the characteristic surface constituents (Fig. , Table ) The difference between the relative electronegativity between Mg and Mn is 0.24. Therefore, the formation of Mg-Mn IMPs is more expected than Mg-Al, which is also supported by the XRD data .