Abstract:The pattern of making round billets by spray forming technology was studied by means of numerical method combined with experiment. The results show that during the atomization deposition process, the shape of the deposit reaches a stable state after a primary transient state, and then the round billet grows in the mode of equi-diameter. The basic condition to reach the stable state is that the withdraw velocity of the collector,v,is smaller thanacos, whereais the atomization density along the atomization axis, andis the atomization angle. With the other technological parameters being constant, round billets with different diameters can be made by adjusting the withdraw velocity. Additionally, the ratio of gas flux to melt flux(G/M)
also directly affects the shaping of round billets in the atomization deposition process.

Key words: spray forming　round billets　numerical method　ratio of gas flux to melt flux