A process for manufacturing metal powders including: i) feeding an atomization chamber of a gas atomizer with molten metal, (ii) atomizing the molten metal by injection of gas so as to form metal particles, (iii) transferring the metal particles from the atomization chamber to a cooling chamber of the gas atomizer, (iv) cooling the metal particles in the cooling chamber by injecting gas from the bottom of the cooling chamber so as to form a bubbling fluidized bed of metal particles. A gas atomizer thereof is also provided.