K. L. and B. J. Kosanke
ABSTRACT: A variety of flash powders were tested under weak confinement to determine the sound pressure levels and tonal characteristics produced. In these tests it was found that: the sound output from mixtures prepared with potassium perchlorate from four manufacturers are essentially equivalent; there are significant differences in the level of sound output as a result of using six different common aluminum powders; the addition of either of two common flow or bulking agents have essentially no effect on the sound produced; the substitution of potassium chlorate for potassium perchlorate in a common flash powder has essentially no effect on the sound produced; and the addition of antimony sulfide or sulfur reduces the duration of positive phase without increasing the level of the sound produced. In short, it was found that nothing surpassed the level of sound produced by a 70:30 mixture of reasonably high-quality potassium perchlorate and a high quality flake aluminum powder. This is significant because the use of potassium chlorate, antimony sulfide, and sulfur, can seriously increase the sensitiveness of flash powders to accidental ignition.
Keywords: flash powder, sound pressure level, blast pressure, weak confinement, positive phase
Ref: JPyro, Issue 4, 1996, pp5-15
(J4_5)
© Journal of Pyrotechnics and CarnDu Ltd
*Flash Powder* The most fascinating of all pyrotechnic mixtures!!!
I absolutely loved this article, along with Blast Waves and Flash Powder. I thank all persons involved with this project for their time and hard work.
My only criticism is that if there is to be a part 2 to this, I would love to see something along the lines of; Flash-the best every oxidizer has to offer. It was quite clear that KCLO3 & KCLO4 both preform about the same. The key to fast flash was in the aluminum powder used.
I would of hoped that in the Barium Nitrate flash tested you would of used 5413H instead of the Alcan 2000. I think the results would of been better. But I would love to see a similar project done with focus spent on the many oxidizers available with the highest quality aluminum, magnalium and even magnesium. Just to see the limit you could take any oxidizer.
Could you get KCLO4 + G.D. (70/30) performance out of a KNO3 or Ba(NO3)2 mixture??? THANKS!!!!