Study on Combustion Characteristics and Kinetics of Boron in Different Atmosphere

In order to investigate the combustion characteristics of boron in air,CO 2,N 2 and O 2 respectively,experiments were carried out with a high-temperature thermal balance at 50~1 100 ℃.Effect of particle size on the ignition temperature of boron was also studied.The single-curve model of Doyle integral method was adopted to calculate the kinetic parameters of the thermal reaction of boron under different atmosphere.The results show that the weight gain rate of boron in O 2 is highest.The weight gain in CO 2 is the most and least in N 2 on the contrary.The ignition temperature of boron in air,O 2 and CO 2 is 710,697,770 ℃ respectively,which leads to the conclusion that increasing oxygen concentration can notably improve the ignition of boron.The ignition temperature increases slightly with the increasing of particle size.According to the kinetic calculation,the reaction of boron in air,O 2 and CO 2 are all belong to second order reaction and the rate constant in CO 2 is the minimum.The analysis of combustion products shows that the reaction between boron and O 2 is the dominant reaction in air.