Effects of coating agents on the ignition and combustion of boron particles

Boron is an attractive candidate for the development of high-energy fuels.It is important to find ways for promoting ignition and combustion property of boron particles.In this paper,AP,LiF and TMP were used for boron surface coating.Then ignition and combustion behavior of original boron and coated boron were studied by using thermogravimetry coupled with differential scanning calorimetry(TG-DCS) and laser ignition test bench.Results show that the thermal reaction of boron in the air can be divided into three stages:warm-up period,violent reaction period and later reaction period.LiF and TMP can reduce the ignition temperature and increase heat release of the boron samples.AP can slightly raise the ignition temperature and decrease the boron heat release.During laser ignition test,AP can shorten the ignition delay time and improve the combustion intensity.On the other side,LiF and TMP can increase the ignition delay time and lower combustion intensity a little,because they absorb part of the energy from the laser.