In the particle-induced kinetic electron emission from solids the role of different excitation and scattering processes is of special interest from both the theoretical and the experimental point of view. Calculations of the emission characteristics were performed for different nearly-free-electron metals. Depending on the impact energy the relative importance of different excitation mechanisms will be discussed for Mg and Be in comparison with the results for the standard material Al. There are characteristic features related to the different strength of plasmon damping in these metals. The role of different scattering processes (elastic, inelastic) which determine the transport of excited electrons towards the surface will be discussed in relation to the special features shown by the various excitation processes.