In order to understand the quick heat dissipation of ignition-proof behavior in the spray forming magnesium alloy with nitrogen as atomizing gas

the heat transfer between magnesium alloy droplet and gas during spray forming process were simulated by mathematical model.The results show that the atomizing gas velocity is decreased monotonically with the increases of spray distance.Droplet velocity increased firstly

and then decreased when it is equal to the gas velocity.Meanwhile

the maximum velocity is decreased with the increase of particle size.Heat transfer coefficient is decreased firstly and then increased

and it is increased with the decrease of particle size.The average heat transfer coefficient is more than 1 000 W·m-2·K-1.In addition

the temperature of the droplet is reduced.In the atomization stage

minimum velocity of heat transfer is far greater than maximum velocity of the heat released by the reaction between magnesium and nitrogen

so the production safety of spray deposited magnesium alloy with nitrogen as the atomizing gas is ensured as a result of eliminating the accumulation of heat during spray deposition.