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Static recrystallization and grain growth behaviors were investigated in Mg-0.3Ce (wt%) alloy processed by equal-channel angular pressing (ECAP) for N = 1 (eeq = 0.9), 2 (eeq = 1.9), and 4 (eeq = 3.9) passes at 300 °C using route Bc and annealed at 450 °C for 5, 30, 60, and 180 min. The results demonstrated that the annealed microstructure and texture are strongly related to the strain level, second particles distribution, and fraction of dynamic recrystallization (DRX) during ECAP. At low strain (1 ECAP pass), the microstructure was very heterogeneous and the texture development changed with increasing annealing time due to the absence of sufficient recrystallization nucleation sites and pinning effect of second particles. At medium strain (2 ECAP passes), the microstructure was homogeneous, however, the texture was unstable mainly due to the limited DRX during ECAP processing leading to the preferred grain growth. At high strain (4 ECAP passes), the microstructure was homogeneous and the texture was retained throughout the entire annealing duration due to the significant amount of DRX.

We conducted an inter-laboratory study of a metallic glass whose main component is nickel. Two determinations of the mass fractions of the different elements present within the sample were asked to the participants: one at an acceleration voltage of 15 or 20 kV and another one at 5 kV. We compare the mass fractions obtained from wavelength dispersive (WDS) and energy dispersive spectrometries (EDS) and also try to find an influence of the kind of EDS detector and its entrance window, the background subtraction method, the use or not of standards as well as the quantification method. Both means of WDS and EDS mass fractions are close to the reference values. The dispersion of the results was larger at 5 kV than at 15-20 kV owing to the use of the L lines rather than K lines and to the lowest collected intensities. There is an exception with the case of boron because at the lowest voltage, the excitation condition is more favourable for the production of the K line. It appears that the dispersion of the results is larger with EDS than with WDS but it was not possible to find a correlation between the large dispersion and one of the considered experimental parameters and quantification factors. Thus, one can think that electron microprobes are inherently better for the determination of mass fractions or that the implementation of quantitative analysis must be optimized for some cases, especially in SEMs., Comment: Members of the GN-MEBA, SEMPA users group and Belgian laboratories coordinated by Universite Catholique de Louvain are thanked for their participation to this inter-laboratory study