Differences in chemical composition among main sequence stars within a given cluster are probably due to differences in their masses and other effects such as radiative diffusion, magnetic field, rotation, mixing mechanisms, mass loss, accretion and
multiplicity. The early type main-sequence members of open clusters of different ages allow to study the competition between radiative diffusion and mixing mechanisms. We have analysed low and high resolution spectra covering the spectral range 4500 - 5840 Angs. of late B, A, and F type members of the open Cluster M6 (age about 100 Myr). The spectra were obtained using the FLAMES/GIRAFFE spectrograph mounted at UT2, the 8 meter class VLT telescope. The effective temperatures, surface gravities and microturbulent velocities of the stars were derived using both photometric and spectral methods. We have also performed a chemical abundance analysis using synthetic spectra. The abundances of the elements were determined for C, O, Mg, Si, Ca, Sc, Ti, Cr, Mn, Fe, Ni, Y, Ba. The star-to-star variations in elemental abundances among the members of the open cluster M6 were discussed.
