Electrode Induction melting Gas Atomization (EIGA) is a free-fall gas atomization process used to produce metal powders, where a swirling supersonic gas jet hits a molten metal stream atomizing it into droplets through various fragmentation mechanisms. Fragmentation mechanisms of molten Ti64 are investigated by high-speed video visualization. The role of gas pressure and melting chamber overpressure on the fragmentation mechanisms and on the particle size distribution is determined. The mechanisms observed are fiber breakup, bag breakup and Rayleigh breakup for primary fragmentation and bag breakup and shear breakup for secondary fragmentation. Increasing the gas pressure promotes shear breakup and creates finer droplets. A model based on log-stable law is proposed to fit the mass distribution according to the dominant fragmentation regime. A good agreement is observed between the different analysis (dominant atomization regime, mass cumulative distribution evolution, parameters of log-stable law). A criterion for prediction of nozzle clogging is devised.