Bulk single crystals of the ternary intermetallic compounds UT2Si2 (T = Ni, Pd, Pt and Ru), LaT2Si2 (T = Pd and Rh) and LuPd2Si2 have been grown from the melt with a modified "tri-arc" Czochralski method. The as-grown crystals were characterized by X-ray, microprobe and chemical analyses. The measured densities are compared with the calculated densities as obtained from the lattice parameters. A detailed metallography analysis of both polycrystalline and single-crystalline samples shows that the Mt2Si2 intermetallics exist only in a very narrow homogeneity range and that the segregation of second phase is almost always present in polycrystalline samples and can severely mask the intrinsic properties of these materials. The effect of heat treatment on the electrical resistivity of single-crystalline URu2Si2 is presented, along with some preliminary results on the crystal growth of URh2Ge2.