SPRAY-FORMING DEPOSITION METHOD

PROBLEM TO BE SOLVED: To provide a spray-forming deposition method for forming a preform, which prevents the occurrence of vacancy portions resulting from temperature variation of the preform or crack due to thermal stress and can achieve yield improvement.SOLUTION: The spray-forming deposition method is used for forming a preform 8 by depositing, on a moving collector 5, the metallic droplets 7 sprayed by jetting a gas to a flow-down molten metal M. A heater 6 is disposed inside or in the vicinity of the collector 5, and the metallic droplets 7 are sequentially deposited on the collector 5 while preheating the collector 5 by the heater 6.