Heat and Glow Powder

[Skylighter]

This video was originally posted on Glow Forum, but I thought you guys would get a kick out of it.

http://www.youtube.com/watch?v=SsEWYUhIOdw

A customer of ours heats a fork and then draws with it in V10 powder. Thanks to Spacehead for the video.

 

[bhds]

Neat!
I dont get it though:thinking: Splain please.

 

[X_Marine]

Got to luv the effect..

ThanX
X..

 

[worldedit]

I saw the effect when i soldered a glow modded led. It goes really bright, but i dont think its good for the glow powder.

 

[Skylighter]

bhds,

Glow powder is phosphorescent pigment. It collects light and releases it slowly creating a glow effect. But heating it also causes it to glow. This is a demonstration to that effect.

On Glow Forum, we discussed why it glows when heated. It is either a) the heat is charging it rapidly or b) the heat is discharging it rapidly.

 

[worldedit]

Ask a physicist

The light from glow material comes from excited electrons. These go back to their ground state in a complex process. This process happens more likely at higher temperature. So the heat is discharging the glow faster.

Lets see if the other explanation is also true.
At the temperature red glowing iron has, the molecules in the glow get a mean value of 1.38*10^-20 J. A photon at green wavelenght however has about 3.75*10^-19 J. To excite the electron you need a minimum of this energy. You can see this is 30 times the energy you get from the heat.

You might get a little charge from the heat, but the higher discharge rate will by far outweigh it.

Do you know at which temperature the glow is destroyed (melds, burns, changes otherwise)?

 

[Skylighter]

worldedit,

Thanks for that information. I have been trying to confirm that for over a year. If you dont mind, I will copy this post to the discussion thread on Glow Forum.

I beleive the glow material melts somewhere between 2000F and 2500F.

Do you have any idea how we can calculate the optimum wavelength for charging?

 

[worldedit]

Im not that into nuclear physics. Of course you need a shorter wave lenght than the powder glows with. The perfect wave lenght depends on the color the powder has under sunlight. Green glow looks yellow because it can absorb wave lenght shorter than violett (440nm). I dont know though if violet is best to charge green glow or if its the shorter the better.